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http://rosettacode.org/wiki/General_FizzBuzz
General FizzBuzz
Task Write a generalized version of FizzBuzz that works for any list of factors, along with their words. This is basically a "fizzbuzz" implementation where the user supplies the parameters. The user will enter the max number, then they will enter the factors to be calculated along with the corresponding word to be printed. For simplicity's sake, assume the user will input an integer as the max number and 3 factors, each with a word associated with them. For example, given: >20 #This is the maximum number, supplied by the user >3 Fizz #The user now enters the starting factor (3) and the word they want associated with it (Fizz) >5 Buzz #The user now enters the next factor (5) and the word they want associated with it (Buzz) >7 Baxx #The user now enters the next factor (7) and the word they want associated with it (Baxx) In other words: For this example, print the numbers 1 through 20, replacing every multiple of 3 with "Fizz", every multiple of 5 with "Buzz", and every multiple of 7 with "Baxx". In the case where a number is a multiple of at least two factors, print each of the words associated with those factors in the order of least to greatest factor. For instance, the number 15 is a multiple of both 3 and 5; print "FizzBuzz". If the max number was 105 instead of 20, you would print "FizzBuzzBaxx" because it's a multiple of 3, 5, and 7. Output: 1 2 Fizz 4 Buzz Fizz Baxx 8 Fizz Buzz 11 Fizz 13 Baxx FizzBuzz 16 17 Fizz 19 Buzz
#Java
Java
public class FizzBuzz {   public static void main(String[] args) { Sound[] sounds = {new Sound(3, "Fizz"), new Sound(5, "Buzz"), new Sound(7, "Baxx")}; for (int i = 1; i <= 20; i++) { StringBuilder sb = new StringBuilder(); for (Sound sound : sounds) { sb.append(sound.generate(i)); } System.out.println(sb.length() == 0 ? i : sb.toString()); } }   private static class Sound { private final int trigger; private final String onomatopoeia;   public Sound(int trigger, String onomatopoeia) { this.trigger = trigger; this.onomatopoeia = onomatopoeia; }   public String generate(int i) { return i % trigger == 0 ? onomatopoeia : ""; }   }   }
http://rosettacode.org/wiki/Hailstone_sequence
Hailstone sequence
The Hailstone sequence of numbers can be generated from a starting positive integer,   n   by:   If   n   is     1     then the sequence ends.   If   n   is   even then the next   n   of the sequence   = n/2   If   n   is   odd   then the next   n   of the sequence   = (3 * n) + 1 The (unproven) Collatz conjecture is that the hailstone sequence for any starting number always terminates. This sequence was named by Lothar Collatz in 1937   (or possibly in 1939),   and is also known as (the):   hailstone sequence,   hailstone numbers   3x + 2 mapping,   3n + 1 problem   Collatz sequence   Hasse's algorithm   Kakutani's problem   Syracuse algorithm,   Syracuse problem   Thwaites conjecture   Ulam's problem The hailstone sequence is also known as   hailstone numbers   (because the values are usually subject to multiple descents and ascents like hailstones in a cloud). Task Create a routine to generate the hailstone sequence for a number. Use the routine to show that the hailstone sequence for the number 27 has 112 elements starting with 27, 82, 41, 124 and ending with 8, 4, 2, 1 Show the number less than 100,000 which has the longest hailstone sequence together with that sequence's length.   (But don't show the actual sequence!) See also   xkcd (humourous).   The Notorious Collatz conjecture Terence Tao, UCLA (Presentation, pdf).   The Simplest Math Problem No One Can Solve Veritasium (video, sponsored).
#Z80_Assembly
Z80 Assembly
;;;;;;;;;;;;;;;;;;; HEADER  ;;;;;;;;;;;;;;;;;;; read "\SrcCPC\winape_macros.asm" read "\SrcCPC\MemoryMap.asm" read "\SrcALL\winapeBuildCompat.asm" ;;;;;;;;;;;;;;;;;;; PROGRAM  ;;;;;;;;;;;;;;;;;;;   org &8000 ld de,27 call doHailstone ;returns length of sequence, and writes each entry in the sequence ; to RAM   ;print the sequence length (in hex) ld a,h call ShowHex ld a,l ld (memdump_smc),a ;just to prove I didn't need to know the sequence length at ; compile time, I'll store the calculated length as the operand ; of "doMemDump" which normally takes a constant embedded after ; it as the number of bytes to display.   ; If that doesn't make sense, don't worry. ; This has nothing to do with calculating the hailstone sequence, just showing the results. call ShowHex   call NewLine ;prints CRLF call NewLine   call doMemDump memdump_smc: byte 0 ;operand of "doMemDump" (gets overwritten with the sequence length) word HailstoneBuffer ;operand of "doMemDump"     ret   ;;;;;;;;;;;;;;;;;;; LIBRARY  ;;;;;;;;;;;;;;;;;;; read "\SrcCPC\winape_stringop.asm" read "\SrcCPC\winape_showhex.asm"     doHailstone: ;you need the proper input for the function "hailstone" ;returns addr. of last element in IX. call hailstone ld de,HailstoneBuffer or a ;clear carry push ix pop hl ;returns element count in HL. sbc hl,de ;subtract the two to get the length of the array.   SRL H RR L ;divide array size by 2, since each entry is 2 bytes. INC L ret nz ;if no carry, don't increment H. INC H ret     hailstone: ;input - de = n ld ix,HailstoneBuffer ld a,d or e ret z ;zero is not allowed. loop_hailstone: ld (IX+0),e ld (IX+1),d ld a,e cp 1 jr nz,continue_hailstone ld a,d or a ret z ;if de = 1, stop. continue_hailstone: bit 0,e jr z,DE_IS_EVEN ;de is odd push de pop hl ;ld hl,de   SLA E RL D add hl,de ;hl = de*3   ld de,1 add hl,de   push hl pop de ;ld de,hl   inc ix inc ix jr loop_hailstone   DE_IS_EVEN: SRL D ;A/2 RR E inc ix inc ix jr loop_hailstone     doMemDump: ;show the hailstone sequence to the screen. This is just needed to display the data, if you don't care about that ;you can stop reading here. pop hl ;get PC ld b,(hl) ;get byte count inc hl ld e,(hl) ;get low byte of start addr. inc hl ld d,(hl) ;get high byte of start addr. inc hl push hl ;now when we return we'll skip the data block. ex de,hl     call NewLine   ;we'll dump 8 words per line.   ld c,8 loop_doMemDump: inc hl ld a,(hl) call ShowHex dec hl ld a,(hl) call ShowHex ld a,' ' call PrintChar inc hl inc hl dec c ld a,c and %00001111 jr nz,continueMemdump ld c,8 continueMemdump: djnz loop_doMemDump ret       HailstoneBuffer: ds 512,0
http://rosettacode.org/wiki/Generate_lower_case_ASCII_alphabet
Generate lower case ASCII alphabet
Task Generate an array, list, lazy sequence, or even an indexable string of all the lower case ASCII characters, from a to z. If the standard library contains such a sequence, show how to access it, but don't fail to show how to generate a similar sequence. For this basic task use a reliable style of coding, a style fit for a very large program, and use strong typing if available. It's bug prone to enumerate all the lowercase characters manually in the code. During code review it's not immediate obvious to spot the bug in a Tcl line like this contained in a page of code: set alpha {a b c d e f g h i j k m n o p q r s t u v w x y z} Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Delphi
Delphi
program atoz;   var ch : char;   begin for ch in ['a'..'z'] do begin write(ch); end; end.
http://rosettacode.org/wiki/Generate_lower_case_ASCII_alphabet
Generate lower case ASCII alphabet
Task Generate an array, list, lazy sequence, or even an indexable string of all the lower case ASCII characters, from a to z. If the standard library contains such a sequence, show how to access it, but don't fail to show how to generate a similar sequence. For this basic task use a reliable style of coding, a style fit for a very large program, and use strong typing if available. It's bug prone to enumerate all the lowercase characters manually in the code. During code review it's not immediate obvious to spot the bug in a Tcl line like this contained in a page of code: set alpha {a b c d e f g h i j k m n o p q r s t u v w x y z} Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Draco
Draco
/* Generate the lowercase alphabet and store it in a buffer */ proc alph(*char buf) *char: channel output text ch; char letter; open(ch, buf); for letter from 'a' upto 'z' do write(ch; letter) od; close(ch); buf corp   /* Use the function to print the alphabet */ proc main() void: [27] char buf; /* one byte extra for the string terminator */ writeln(alph(&buf[0])) corp
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#Ol
Ol
(print "Hello world!")
http://rosettacode.org/wiki/Generator/Exponential
Generator/Exponential
A generator is an executable entity (like a function or procedure) that contains code that yields a sequence of values, one at a time, so that each time you call the generator, the next value in the sequence is provided. Generators are often built on top of coroutines or objects so that the internal state of the object is handled “naturally”. Generators are often used in situations where a sequence is potentially infinite, and where it is possible to construct the next value of the sequence with only minimal state. Task Create a function that returns a generation of the m'th powers of the positive integers starting from zero, in order, and without obvious or simple upper limit. (Any upper limit to the generator should not be stated in the source but should be down to factors such as the languages natural integer size limit or computational time/size). Use it to create a generator of:   Squares.   Cubes. Create a new generator that filters all cubes from the generator of squares. Drop the first 20 values from this last generator of filtered results, and then show the next 10 values. Note that this task requires the use of generators in the calculation of the result. Also see Generator
#Kotlin
Kotlin
// version 1.1.0 // compiled with flag -Xcoroutines=enable to suppress 'experimental' warning   import kotlin.coroutines.experimental.buildSequence   fun generatePowers(m: Int) = buildSequence { var n = 0 val mm = m.toDouble() while (true) yield(Math.pow((n++).toDouble(), mm).toLong()) }   fun generateNonCubicSquares(squares: Sequence<Long>, cubes: Sequence<Long>) = buildSequence { val iter2 = squares.iterator() val iter3 = cubes.iterator() var square = iter2.next() var cube = iter3.next() while (true) { if (square > cube) { cube = iter3.next() continue } else if (square < cube) { yield(square) } square = iter2.next() } }   fun main(args: Array<String>) { val squares = generatePowers(2) val cubes = generatePowers(3) val ncs = generateNonCubicSquares(squares, cubes) print("Non-cubic squares (21st to 30th) : ") ncs.drop(20).take(10).forEach { print("$it ") } // print 21st to 30th items println() }
http://rosettacode.org/wiki/Greatest_common_divisor
Greatest common divisor
Greatest common divisor You are encouraged to solve this task according to the task description, using any language you may know. Task Find the greatest common divisor   (GCD)   of two integers. Greatest common divisor   is also known as   greatest common factor (gcf)   and   greatest common measure. Related task   least common multiple. See also   MathWorld entry:   greatest common divisor.   Wikipedia entry:     greatest common divisor.
#XLISP
XLISP
(defun greatest-common-divisor (x y) (if (= y 0) x (greatest-common-divisor y (mod x y)) ) )
http://rosettacode.org/wiki/Greatest_common_divisor
Greatest common divisor
Greatest common divisor You are encouraged to solve this task according to the task description, using any language you may know. Task Find the greatest common divisor   (GCD)   of two integers. Greatest common divisor   is also known as   greatest common factor (gcf)   and   greatest common measure. Related task   least common multiple. See also   MathWorld entry:   greatest common divisor.   Wikipedia entry:     greatest common divisor.
#XPL0
XPL0
include c:\cxpl\codes;   func GCD(U, V); \Return the greatest common divisor of U and V int U, V; int T; [while V do \Euclid's method [T:= U; U:= V; V:= rem(T/V)]; return abs(U); ];   \Display the GCD of two integers entered on command line IntOut(0, GCD(IntIn(8), IntIn(8)))
http://rosettacode.org/wiki/Generate_Chess960_starting_position
Generate Chess960 starting position
Chess960 is a variant of chess created by world champion Bobby Fischer. Unlike other variants of the game, Chess960 does not require a different material, but instead relies on a random initial position, with a few constraints: as in the standard chess game, all eight white pawns must be placed on the second rank. White pieces must stand on the first rank as in the standard game, in random column order but with the two following constraints: the bishops must be placed on opposite color squares (i.e. they must be an odd number of spaces apart or there must be an even number of spaces between them) the King must be between two rooks (with any number of other pieces between them all) Black pawns and pieces must be placed respectively on the seventh and eighth ranks, mirroring the white pawns and pieces, just as in the standard game. (That is, their positions are not independently randomized.) With those constraints there are 960 possible starting positions, thus the name of the variant. Task The purpose of this task is to write a program that can randomly generate any one of the 960 Chess960 initial positions. You will show the result as the first rank displayed with Chess symbols in Unicode: ♔♕♖♗♘ or with the letters King Queen Rook Bishop kNight.
#PicoLisp
PicoLisp
(load "@lib/simul.l")   (seed (in "/dev/urandom" (rd 8)))   (loop (match '(@A B @B B @C) (shuffle '(Q B B N N 0 0 0)) ) (NIL (bit? 1 (length @B))) )   (let Rkr '(R K R) (for I (append @A '(B) @B '(B) @C) (prin (if (=0 I) (pop 'Rkr) I)) ) (prinl) )   (bye)
http://rosettacode.org/wiki/Generate_Chess960_starting_position
Generate Chess960 starting position
Chess960 is a variant of chess created by world champion Bobby Fischer. Unlike other variants of the game, Chess960 does not require a different material, but instead relies on a random initial position, with a few constraints: as in the standard chess game, all eight white pawns must be placed on the second rank. White pieces must stand on the first rank as in the standard game, in random column order but with the two following constraints: the bishops must be placed on opposite color squares (i.e. they must be an odd number of spaces apart or there must be an even number of spaces between them) the King must be between two rooks (with any number of other pieces between them all) Black pawns and pieces must be placed respectively on the seventh and eighth ranks, mirroring the white pawns and pieces, just as in the standard game. (That is, their positions are not independently randomized.) With those constraints there are 960 possible starting positions, thus the name of the variant. Task The purpose of this task is to write a program that can randomly generate any one of the 960 Chess960 initial positions. You will show the result as the first rank displayed with Chess symbols in Unicode: ♔♕♖♗♘ or with the letters King Queen Rook Bishop kNight.
#PowerShell
PowerShell
function Get-RandomChess960Start { $Starts = @()   ForEach ( $Q in 0..3 ) { ForEach ( $N1 in 0..4 ) { ForEach ( $N2 in ($N1+1)..5 ) { ForEach ( $B1 in 0..3 ) { ForEach ( $B2 in 0..3 ) { $BB = $B1 * 2 + ( $B1 -lt $B2 ) $BW = $B2 * 2 $Start = [System.Collections.ArrayList]( '♖', '♔', '♖' ) $Start.Insert( $Q , '♕' ) $Start.Insert( $N1, '♘' ) $Start.Insert( $N2, '♘' ) $Start.Insert( $BB, '♗' ) $Start.Insert( $BW, '♗' ) $Starts += ,$Start }}}}}   $Index = Get-Random 960 $StartString = $Starts[$Index] -join '' return $StartString }   Get-RandomChess960Start Get-RandomChess960Start Get-RandomChess960Start Get-RandomChess960Start  
http://rosettacode.org/wiki/Function_composition
Function composition
Task Create a function, compose,   whose two arguments   f   and   g,   are both functions with one argument. The result of compose is to be a function of one argument, (lets call the argument   x),   which works like applying function   f   to the result of applying function   g   to   x. Example compose(f, g) (x) = f(g(x)) Reference: Function composition Hint: In some languages, implementing compose correctly requires creating a closure.
#Agda
Agda
compose : ∀ {a b c} {A : Set a} {B : Set b} {C : Set c} → (B → C) → (A → B) → A → C compose f g x = f (g x)
http://rosettacode.org/wiki/Function_composition
Function composition
Task Create a function, compose,   whose two arguments   f   and   g,   are both functions with one argument. The result of compose is to be a function of one argument, (lets call the argument   x),   which works like applying function   f   to the result of applying function   g   to   x. Example compose(f, g) (x) = f(g(x)) Reference: Function composition Hint: In some languages, implementing compose correctly requires creating a closure.
#Aikido
Aikido
  import math   function compose (f, g) { return function (x) { return f(g(x)) } }   var func = compose(Math.sin, Math.asin) println (func(0.5)) // 0.5    
http://rosettacode.org/wiki/FTP
FTP
Task Connect to a server, change directory, list its contents and download a file as binary using the FTP protocol. Use passive mode if available.
#C.2B.2B
C++
/* client.cpp   libftp++ C++ classes for ftplib C ftp library   compile: clang++ -std=c++11 -o client client.cpp -lftp++ */   #include <iostream> #include <string> #include <cstring> #include <fstream> #include <sys/stat.h> // stat #include <ftplib.h> // libftp #include <ftp++.hpp> // libftp++     /* C++ classes:   Connection main ftp connection (user class)   ConnectionBase base class for Connection (internal)   DataConnection connection type, (internal) read bytes from server, write bytes to server   ConnectionException custom exception (thrown by Connection)   */     /** ftp::Connection class API   data members: A Connection instance contains only a pointer as a data member   { protected: netbuf * conn; // pointer to ftplib netbuf struct }   member functions:   connect:   Connection(const char * host); // constructor   void setConnectionMode(Mode mode); // passive or port   void login(const char * user, const char * password); // Log in   info:   const char * getLastResponse(); // last server response   std::string getSystemType(); // server type   std::string getDirectory(); // remote pwd   void getList(const char * filename, const char * path); // short dir list   unsigned size(const char * path, TransferMode mode);   file transfer:   void get(const char * local, const char * remote, TransferMode mode);   void put(const char * local, const char * remote, TransferMode mode);   **/   // libc functions int stat(const char *pathname, struct stat *buf); // local file info char *strerror(int errnum); // explanation of error char *basename(char *path); // filename at end of path     // STL classes and functions used namespace stl { using std::cout; // stdout using std::cerr; // stderr using std::string; // string using std::ifstream; // files on disk using std::remove; // delete file on disk };   using namespace stl;     // connection modes using Mode = ftp::Connection::Mode; Mode PASV = Mode::PASSIVE; Mode PORT = Mode::PORT;   //file transfer modes using TransferMode = ftp::Connection::TransferMode; TransferMode BINARY = TransferMode::BINARY; TransferMode TEXT = TransferMode::TEXT;     /* ********************** */ // ftp session parameters struct session { const string server; // server name const string port; // usually 21 const string user; // username const string pass; // password Mode mode; // PASV, PORT TransferMode txmode; // BINARY, TEXT string dir; // current or default dir };   /* ********************** */ // local helper functions   ftp::Connection connect_ftp( const session& sess); size_t get_ftp( ftp::Connection& conn, string const& path); string readFile( const string& filename); string login_ftp(ftp::Connection& conn, const session& sess); string dir_listing( ftp::Connection& conn, const string& path);     /* ******************************** */ // Read a file into one long string   string readFile( const string& filename) { struct stat stat_buf; string contents;   errno = 0; if (stat(filename.c_str() , &stat_buf) != -1) // file stats { size_t len = stat_buf.st_size; // size of file   string bytes(len+1, '\0'); // string big enough   ifstream ifs(filename); // open for input   ifs.read(&bytes[0], len); // read all bytes as chars into string   if (! ifs.fail() ) contents.swap(bytes); // swap into contents   ifs.close(); } else { cerr << "stat error: " << strerror(errno); }   return contents; }   /* *************** */ // start a session   ftp::Connection connect_ftp( const session& sess) try { string constr = sess.server + ":" + sess.port;   cerr << "connecting to " << constr << " ...\n";   ftp::Connection conn{ constr.c_str() };   cerr << "connected to " << constr << "\n"; conn.setConnectionMode(sess.mode);   return conn; } catch (ftp::ConnectException e) { cerr << "FTP error: could not connect to server" << "\n"; }   /* ***** */ // login   string login_ftp(ftp::Connection& conn, const session& sess) { conn.login(sess.user.c_str() , sess.pass.c_str() );   return conn.getLastResponse(); }   /* ***************************** */ // get remote directory listing   // ftplib writes to file for dir contents // convert file contents to string   string dir_listing( ftp::Connection& conn, const string& path) try { // file on disk to write to const char* dirdata = "/dev/shm/dirdata";   conn.getList(dirdata, path.c_str() ); // conn.getFullList(dirdata, path.c_str() ); // conn.getFullList(NULL, path.c_str() ); // to stdout   string dir_string = readFile(dirdata);   cerr << conn.getLastResponse() << "\n";   errno = 0; if ( remove(dirdata) != 0 ) // delete file on disk { cerr << "error: " << strerror(errno) << "\n"; }   return dir_string; } catch (...) { cerr << "error: getting dir contents: \n" << strerror(errno) << "\n"; }   /* ************************* */ // retrieve file from server   size_t get_ftp( ftp::Connection& conn, const string& r_path) { size_t received = 0;   const char* path = r_path.c_str();   unsigned remotefile_size = conn.size(path , BINARY);   const char* localfile = basename(path);   conn.get(localfile, path, BINARY); // get file   cerr << conn.getLastResponse() << "\n";   // get local file size struct stat stat_buf;   errno = 0; if (stat(localfile, &stat_buf) != -1) received = stat_buf.st_size; else cerr << strerror(errno);   return received; }   /* ******************** */ // default test session const session sonic { "mirrors.sonic.net", "21" , "anonymous", "[email protected]", PASV, BINARY, "/pub/OpenBSD" };   /* **** */ // main   int main(int argc, char* argv[], char * env[] ) { const session remote = sonic; // copy session info   try {   // open an ftp connection ftp::Connection conn = connect_ftp(remote);   // login with username and passwd cerr << login_ftp(conn, remote);   // what type system cout << "System type: " << conn.getSystemType() << "\n"; cerr << conn.getLastResponse() << "\n";   // cd to default session dir conn.cd(remote.dir.c_str()); // change to dir on server cerr << conn.getLastResponse() << "\n";   // get current remote directory string pwdstr = conn.getDirectory(); cout << "PWD: " << pwdstr << "\n"; cerr << conn.getLastResponse() << "\n";     // get file listing string dirlist = dir_listing(conn, pwdstr.c_str() ); cout << dirlist << "\n";   string filename = "ftplist"; // small text file   auto pos = dirlist.find(filename); // find filename in dir list   auto notfound = string::npos;   if (pos != notfound) // found filename { // get file size_t received = get_ftp(conn, filename.c_str() );   if (received == 0) cerr << "got 0 bytes\n"; else cerr << "got " << filename << " (" << received << " bytes)\n"; } else { cerr << "file " << filename << "not found on server. \n"; }   } catch (ftp::ConnectException e) { cerr << "FTP error: could not connect to server" << "\n"; } catch (ftp::Exception e) { cerr << "FTP error: " << e << "\n"; } catch (...) { cerr << "error: " << strerror(errno) << "\n"; }   // logout, connection closes automatically when conn destructs   return 0; } /* END */  
http://rosettacode.org/wiki/Function_prototype
Function prototype
Some languages provide the facility to declare functions and subroutines through the use of function prototyping. Task Demonstrate the methods available for declaring prototypes within the language. The provided solutions should include: An explanation of any placement restrictions for prototype declarations A prototype declaration for a function that does not require arguments A prototype declaration for a function that requires two arguments A prototype declaration for a function that utilizes varargs A prototype declaration for a function that utilizes optional arguments A prototype declaration for a function that utilizes named parameters Example of prototype declarations for subroutines or procedures (if these differ from functions) An explanation and example of any special forms of prototyping not covered by the above Languages that do not provide function prototyping facilities should be omitted from this task.
#JavaScript
JavaScript
  // A prototype declaration for a function that does not require arguments function List() {}   List.prototype.push = function() { return [].push.apply(this, arguments); };   List.prototype.pop = function() { return [].pop.call(this); };   var l = new List(); l.push(5); l.length; // 1 l[0]; 5 l.pop(); // 5 l.length; // 0   // A prototype declaration for a function that utilizes varargs function List() { this.push.apply(this, arguments); }   List.prototype.push = function() { return [].push.apply(this, arguments); };   List.prototype.pop = function() { return [].pop.call(this); };   var l = new List(5, 10, 15); l.length; // 3 l[0]; 5 l.pop(); // 15 l.length; // 2    
http://rosettacode.org/wiki/Function_definition
Function definition
A function is a body of code that returns a value. The value returned may depend on arguments provided to the function. Task Write a definition of a function called "multiply" that takes two arguments and returns their product. (Argument types should be chosen so as not to distract from showing how functions are created and values returned). Related task   Function prototype
#360_Assembly
360 Assembly
DEFFUN CSECT USING DEFFUN,R13 SAVEAREA B PROLOG-SAVEAREA(R15) DC 17F'0' PROLOG STM R14,R12,12(R13) ST R13,4(R15) ST R15,8(R13) LR R13,R15 set base register BEGIN L R2,=F'13' ST R2,X X=13 L R2,=F'17' ST R2,Y Y=17 LA R1,PARMLIST R1->PARMLIST B SKIPPARM PARMLIST DS 0F DC A(X) DC A(Y) SKIPPARM BAL R14,MULTPLIC call MULTPLIC ST R0,Z Z=MULTPLIC(X,Y) RETURN L R13,4(0,R13) epilog LM R14,R12,12(R13) XR R15,R15 set return code BR R14 return to caller * MULTPLIC EQU * function MULTPLIC(X,Y) L R2,0(R1) R2=(A(X),A(Y)) XR R4,R4 R4=0 L R5,0(R2) R5=X L R6,4(R2) R6=Y MR R4,R6 R4R5=R4R5*R6 LR R0,R5 R0=X*Y (R0 return value) BR R14 end function MULTPLIC * X DS F Y DS F Z DS F YREGS END DEFFUN
http://rosettacode.org/wiki/French_Republican_calendar
French Republican calendar
Write a program to convert dates between the Gregorian calendar and the French Republican calendar. The year 1 of the Republican calendar began on 22 September 1792. There were twelve months (Vendémiaire, Brumaire, Frimaire, Nivôse, Pluviôse, Ventôse, Germinal, Floréal, Prairial, Messidor, Thermidor, and Fructidor) of 30 days each, followed by five intercalary days or Sansculottides (Fête de la vertu / Virtue Day, Fête du génie / Talent Day, Fête du travail / Labour Day, Fête de l'opinion / Opinion Day, and Fête des récompenses / Honours Day). In leap years (the years 3, 7, and 11) a sixth Sansculottide was added: Fête de la Révolution / Revolution Day. As a minimum, your program should give correct results for dates in the range from 1 Vendémiaire 1 = 22 September 1792 to 10 Nivôse 14 = 31 December 1805 (the last day when the Republican calendar was officially in use). If you choose to accept later dates, be aware that there are several different methods (described on the Wikipedia page) about how to determine leap years after the year 14. You should indicate which method you are using. (Because of these different methods, correct programs may sometimes give different results for dates after 1805.) Test your program by converting the following dates both from Gregorian to Republican and from Republican to Gregorian: • 1 Vendémiaire 1 = 22 September 1792 • 1 Prairial 3 = 20 May 1795 • 27 Messidor 7 = 15 July 1799 (Rosetta Stone discovered) • Fête de la Révolution 11 = 23 September 1803 • 10 Nivôse 14 = 31 December 1805
#FreeBASIC
FreeBASIC
' version 18 Pluviose 227 ' compile with: fbc -s console ' retained the original comments for then BBC BASIC entry   #Macro rep_leap (_year) ' see comment at the beginning of rep_to_day ((_year +1) Mod 4 = 0 And ((_year +1) Mod 100 <> 0 Or (_year +1) Mod 400 = 0)) #EndMacro   #Macro gre_leap (_year) (_year Mod 4 = 0 And (_year Mod 100 <> 0 Or _year Mod 400 = 0)) #EndMacro   Dim Shared As UInteger gregorian(11) => {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31} Dim Shared As String gregorian_s(11), republican(11), sanscolottides(5) ' 7-bit ASCII encoding, so no accents on French words Data "January", "February", "March", "April", "May", "June" Data "July", "August", "September", "October", "November", "December" Data "Vendemiaire", "Brumaire", "Frimaire","Nivose", "Pluviose", "Ventose" Data "Germinal", "Floreal", "Prairial", "Messidor", "Thermidor", "Fructidor" Data "Fete de la Vertu", "Fete du Genie", "Fete du Travail", "Fete de l'Opinion" Data "Fete des Recompenses","Fete de la Revolution" Restore For i As UInteger = 0 To 11 Read gregorian_s(i) Next For i As UInteger = 0 To 11 Read republican(i) Next For i As UInteger = 0 To 5 Read sanscolottides(i) Next   Sub split(s As String, ByRef d As UInteger, ByRef m As UInteger, ByRef y As UInteger)   Dim As String month_and_year, Month Dim As UInteger i   s = LCase(Trim(s)) : d = 0 : m = 0 : y = 0 If Left(s,4) = "fete" Then m = 13 For i = 0 To 5 If Left(s, Len(sanscolottides(i))) = LCase(sanscolottides(i)) Then d = i +1 y = Val(Right(s, Len(s) - Len(sanscolottides(i)) -1)) End If Next Else d = Val(Left(s, InStr(s, " ") -1)) month_and_year = Mid(s, InStr(s, " ") +1) Month = Left(month_and_year, InStr(month_and_year, " ") -1) y = Val(Mid(month_and_year, InStr(month_and_year, " ") +1)) If y < 1792 Then For i = 0 To 11 If LCase(republican(i)) = Month Then m = i +1 Next Else For i = 0 To 11 If LCase(gregorian_s(i)) = Month Then m = i +1 Next End If End If   End Sub   Sub day_to_gre(Day As UInteger, ByRef d As UInteger, ByRef m As UInteger, ByRef y As UInteger)   y = Fix(Day / 365.25) d = Day - Fix(365.25 * y) + 21 y += 1792 d += y \ 100 - y \ 400 - 13 m = 8   While d > gregorian(m) d -= gregorian(m) m += 1 If m = 12 Then m = 0 y += 1 If gre_leap(y) Then gregorian(1) = 29 Else gregorian(1) = 28 End If Wend gregorian(1) = 28 m += 1   End Sub   Function gre_to_day(d As UInteger, m As UInteger, y As UInteger) As UInteger   ' modified & repurposed from code given at ' https://www.staff.science.uu.nl/~gent0113/calendar/isocalendar_text5.htm   If m < 3 Then y -= 1 m += 12 End If Return Fix(365.25 * y) - y \ 100 + y \ 400 + Fix(30.6 * (m +1)) + d - 654842   End Function   Function rep_to_day(d As UInteger, m As UInteger, y As UInteger) As UInteger   ' assume that a year is a leap year iff the _following_ year is ' divisible by 4, but not by 100 unless also by 400 ' ' other methods for computing republican leap years exist   If m = 13 Then m -= 1 d += 30 End If If rep_leap(y) Then d -= 1   Return 365 * y + (y +1) \ 4 - (y +1) \ 100 + (y +1) \ 400 + 30 * m + d - 395   End Function   Sub day_to_rep(Day As UInteger, ByRef d As UInteger, ByRef m As UInteger, ByRef y As UInteger)   Dim As UInteger sansculottides = 5   y = Fix(Day / 365.25) If rep_leap(y) Then y -= 1 d = Day - Fix(365.25 * y) + (y +1) \ 100 - (y +1) \ 400 y += 1 m = 1 If rep_leap(y) Then sansculottides = 6 While d > 30 d -= 30 m += 1 If m = 13 Then If d > sansculottides Then d -= sansculottides m = 1 y += 1 If rep_leap(y) Then sansculottides = 6 Else sansculottides = 5 End If End If Wend   End Sub   ' ------=< main >=------   Dim As UInteger Day, Month, Year Dim As String src   Print "*** French Republican ***" Print "*** calendar converter ***" Print "Enter a date to convert, in the format 'day month year'" Print "e.g.: 1 Prairial 3," Print " 20 May 1795." Print "For Sansculottides, use 'day year'" Print "e.g.: Fete de l'opinion 9." Print "Or just press 'RETURN' to exit the program." Print   Do Line Input "> ", src If src <> "" Then split(src, Day, Month, Year) If Day = 0 Or Month = 0 Or Year <= 0 Then Print "Error in input" Continue Do End If ' for simplicity, we assume that years up to 1791 are republican ' and years from 1792 onwards are gregorian If Year < 1792 Then ' convert republican date to number of days elapsed ' since 21 september 1792, then convert that number ' to the gregorian date day_to_gre(rep_to_day(Day, Month, Year),Day, Month, Year) Print; Day; " "; gregorian_s(Month -1); " "; Year Else ' convert gregorian date to republican, via ' number of days elapsed since 21 september 1792 day_to_rep(gre_to_day(Day, Month, Year), Day, Month, Year) If Month = 13 Then Print sanscolottides(Day -1); " "; Year Else Print ; Day; " "; republican(Month -1); " "; Year End If End If End If Loop Until src = ""   End
http://rosettacode.org/wiki/Fusc_sequence
Fusc sequence
Definitions The   fusc   integer sequence is defined as:   fusc(0) = 0   fusc(1) = 1   for n>1,   the   nth   term is defined as:   if   n   is even;     fusc(n) = fusc(n/2)   if   n   is   odd;     fusc(n) = fusc((n-1)/2)   +   fusc((n+1)/2) Note that MathWorld's definition starts with unity, not zero.   This task will be using the OEIS' version   (above). An observation   fusc(A) = fusc(B) where   A   is some non-negative integer expressed in binary,   and where   B   is the binary value of   A   reversed. Fusc numbers are also known as:   fusc function   (named by Dijkstra, 1982)   Stern's Diatomic series   (although it starts with unity, not zero)   Stern-Brocot sequence   (although it starts with unity, not zero) Task   show the first   61   fusc numbers (starting at zero) in a horizontal format.   show the fusc number (and its index) whose length is greater than any previous fusc number length.   (the length is the number of decimal digits when the fusc number is expressed in base ten.)   show all numbers with commas   (if appropriate).   show all output here. Related task   RosettaCode Stern-Brocot sequence Also see   the MathWorld entry:   Stern's Diatomic Series.   the OEIS entry:   A2487.
#Arturo
Arturo
fusc: function [n][ if? or? n=0 n=1 -> n else [ if? 0=n%2 -> fusc n/2 else -> (fusc (n-1)/2) + fusc (n+1)/2 ] ]   print "The first 61 Fusc numbers:" print map 0..61 => fusc   print "\nThe Fusc numbers whose lengths are greater than those of previous Fusc numbers:" print " n fusc(n)" print "--------- ---------" maxLength: 0   loop 0..40000 'i [ f: fusc i l: size to :string f if l > maxLength [ maxLength: l print [ pad to :string i 9 pad to :string f 9 ] ] ]
http://rosettacode.org/wiki/Fusc_sequence
Fusc sequence
Definitions The   fusc   integer sequence is defined as:   fusc(0) = 0   fusc(1) = 1   for n>1,   the   nth   term is defined as:   if   n   is even;     fusc(n) = fusc(n/2)   if   n   is   odd;     fusc(n) = fusc((n-1)/2)   +   fusc((n+1)/2) Note that MathWorld's definition starts with unity, not zero.   This task will be using the OEIS' version   (above). An observation   fusc(A) = fusc(B) where   A   is some non-negative integer expressed in binary,   and where   B   is the binary value of   A   reversed. Fusc numbers are also known as:   fusc function   (named by Dijkstra, 1982)   Stern's Diatomic series   (although it starts with unity, not zero)   Stern-Brocot sequence   (although it starts with unity, not zero) Task   show the first   61   fusc numbers (starting at zero) in a horizontal format.   show the fusc number (and its index) whose length is greater than any previous fusc number length.   (the length is the number of decimal digits when the fusc number is expressed in base ten.)   show all numbers with commas   (if appropriate).   show all output here. Related task   RosettaCode Stern-Brocot sequence Also see   the MathWorld entry:   Stern's Diatomic Series.   the OEIS entry:   A2487.
#AutoHotkey
AutoHotkey
fusc:=[], fusc[0]:=0, fusc[1]:=1, n:=1, l:=0, result:=""   while (StrLen(fusc[n]) < 5) fusc[++n] := Mod(n, 2) ? fusc[floor((n-1)/2)] + fusc[Floor((n+1)/2)] : fusc[floor(n/2)]   while (A_Index <= 61) result .= (result = "" ? "" : ",") fusc[A_Index-1]   result .= "`n`nfusc number whose length is greater than any previous fusc number length:`nindex`tnumber`n" for i, v in fusc if (l < StrLen(v)) l := StrLen(v), result .= i "`t" v "`n"   MsgBox % result
http://rosettacode.org/wiki/Functional_coverage_tree
Functional coverage tree
Functional coverage is a measure of how much a particular function of a system has been verified as correct. It is used heavily in tracking the completeness of the verification of complex System on Chip (SoC) integrated circuits, where it can also be used to track how well the functional requirements of the system have been verified. This task uses a sub-set of the calculations sometimes used in tracking functional coverage but uses a more familiar(?) scenario. Task Description The head of the clean-up crews for "The Men in a very dark shade of grey when viewed at night" has been tasked with managing the cleansing of two properties after an incident involving aliens. She arranges the task hierarchically with a manager for the crews working on each house who return with a breakdown of how they will report on progress in each house. The overall hierarchy of (sub)tasks is as follows, cleaning house1 bedrooms bathrooms bathroom1 bathroom2 outside lavatory attic kitchen living rooms lounge dining room conservatory playroom basement garage garden house2 upstairs bedrooms suite 1 suite 2 bedroom 3 bedroom 4 bathroom toilet attics groundfloor kitchen living rooms lounge dining room conservatory playroom wet room & toilet garage garden hot tub suite basement cellars wine cellar cinema The head of cleanup knows that her managers will report fractional completion of leaf tasks (tasks with no child tasks of their own), and she knows that she will want to modify the weight of values of completion as she sees fit. Some time into the cleaning, and some coverage reports have come in and she thinks see needs to weight the big house2 60-40 with respect to coverage from house1 She prefers a tabular view of her data where missing weights are assumed to be 1.0 and missing coverage 0.0. NAME_HIERARCHY |WEIGHT |COVERAGE | cleaning | | | house1 |40 | | bedrooms | |0.25 | bathrooms | | | bathroom1 | |0.5 | bathroom2 | | | outside_lavatory | |1 | attic | |0.75 | kitchen | |0.1 | living_rooms | | | lounge | | | dining_room | | | conservatory | | | playroom | |1 | basement | | | garage | | | garden | |0.8 | house2 |60 | | upstairs | | | bedrooms | | | suite_1 | | | suite_2 | | | bedroom_3 | | | bedroom_4 | | | bathroom | | | toilet | | | attics | |0.6 | groundfloor | | | kitchen | | | living_rooms | | | lounge | | | dining_room | | | conservatory | | | playroom | | | wet_room_&_toilet | | | garage | | | garden | |0.9 | hot_tub_suite | |1 | basement | | | cellars | |1 | wine_cellar | |1 | cinema | |0.75 | Calculation The coverage of a node in the tree is calculated as the weighted average of the coverage of its children evaluated bottom-upwards in the tree. The task is to calculate the overall coverage of the cleaning task and display the coverage at all levels of the hierarchy on this page, in a manner that visually shows the hierarchy, weights and coverage of all nodes. Extra Credit After calculating the coverage for all nodes, one can also calculate the additional/delta top level coverage that would occur if any (sub)task were to be fully covered from its current fractional coverage. This is done by multiplying the extra coverage that could be gained 1 − c o v e r a g e {\displaystyle 1-coverage} for any node, by the product of the `powers` of its parent nodes from the top down to the node. The power of a direct child of any parent is given by the power of the parent multiplied by the weight of the child divided by the sum of the weights of all the direct children. The pseudo code would be: method delta_calculation(this, power): sum_of_weights = sum(node.weight for node in children) this.delta = (1 - this.coverage) * power for node in self.children: node.delta_calculation(power * node.weight / sum_of_weights) return this.delta Followed by a call to: top.delta_calculation(power=1) Note: to aid in getting the data into your program you might want to use an alternative, more functional description of the starting data given on the discussion page.
#Phix
Phix
-- -- demo\rosetta\Functional_coverage_tree.exw -- ========================================= -- with javascript_semantics constant data = """ NAME_HIERARCHY | WEIGHT | COVERAGE | cleaning | | | house1 |40 | | bedrooms | |0.25 | bathrooms | | | bathroom1 | |0.5 | bathroom2 | | | outside_lavatory | |1 | attic | |0.75 | kitchen | |0.1 | living_rooms | | | lounge | | | dining_room | | | conservatory | | | playroom | |1 | basement | | | garage | | | garden | |0.8 | house2 |60 | | upstairs | | | bedrooms | | | suite_1 | | | suite_2 | | | bedroom_3 | | | bedroom_4 | | | bathroom | | | toilet | | | attics | |0.6 | groundfloor | | | kitchen | | | living_rooms | | | lounge | | | dining_room | | | conservatory | | | playroom | | | wet_room_&_toilet | | | garage | | | garden | |0.9 | hot_tub_suite | |1 | basement | | | cellars | |1 | wine_cellar | |1 | cinema | |0.75 | """ sequence lines = split(data,"\n"), pi = {}, -- indents (to locate parents) pdx = {}, -- indexes for "" children string desc, weights, covers integer parent, child atom weight, coverage, childw = 0 enum DESC, WEIGHT, COVERAGE, PARENT, CHILDREN, CHILDW lines[1] &= " SHARE OF RESIDUE" for i=2 to length(lines) do -- decode text to useable data, link up parents & children {desc,weights,covers} = split(lines[i],"|") -- (nb this assumes /totally/ consistent indenting) integer indent = length(desc)-length(trim_head(desc)), k = find(indent,pi) if k=0 then pi = append(pi,indent) pdx = append(pdx,0) k = length(pi) end if pdx[k] = i parent = 0 if k>1 then parent = pdx[k-1] -- lines[parent][CHILDREN] &= i lines[parent][CHILDREN] = deep_copy(lines[parent][CHILDREN]) & i end if children = {} weight = to_number(trim(weights),1) coverage = to_number(trim(covers),0) lines[i] = {desc, weight, coverage, parent, children, childw} end for for i=length(lines) to 2 by -1 do -- calculate the parent coverages, and save child weight sums children = lines[i][CHILDREN] if length(children) then coverage = 0 childw = 0 for c=1 to length(children) do child = children[c] atom w = lines[child][WEIGHT] coverage += lines[child][COVERAGE]*w childw += w end for lines[i][COVERAGE] = coverage/childw lines[i][CHILDW] = childw -- (save for next loop) end if end for for i=length(lines) to 2 by -1 do -- calculate the share of residue, and format lines child = i {desc, weight, coverage, parent} = lines[i] atom residue = 1-coverage while parent do residue *= lines[child][WEIGHT]/lines[parent][CHILDW] {child, parent} = {parent, lines[parent][PARENT]} end while lines[i] = sprintf("%-32s| %6d | %-8g | %g",{desc,weight,coverage,residue}) end for puts(1,join(lines,"\n")&"\n") {} = wait_key()
http://rosettacode.org/wiki/Function_frequency
Function frequency
Display - for a program or runtime environment (whatever suits the style of your language) - the top ten most frequently occurring functions (or also identifiers or tokens, if preferred). This is a static analysis: The question is not how often each function is actually executed at runtime, but how often it is used by the programmer. Besides its practical usefulness, the intent of this task is to show how to do self-inspection within the language.
#Factor
Factor
USING: accessors kernel math.statistics prettyprint sequences sequences.deep source-files vocabs words ;   "resource:core/sequences/sequences.factor" "sequences" [ path>source-file top-level-form>> ] [ vocab-words [ def>> ] [ ] map-as ] bi* compose [ word? ] deep-filter sorted-histogram <reversed> 7 head .
http://rosettacode.org/wiki/Function_frequency
Function frequency
Display - for a program or runtime environment (whatever suits the style of your language) - the top ten most frequently occurring functions (or also identifiers or tokens, if preferred). This is a static analysis: The question is not how often each function is actually executed at runtime, but how often it is used by the programmer. Besides its practical usefulness, the intent of this task is to show how to do self-inspection within the language.
#Forth
Forth
' noop is bootmessage   \ --- LIST OF CONSTANTS \ WORD# maximum word size \ RING# size of `Rings' element \ DEFS definitions \ KEYS \ \ --- LIST OF VARIABLES \ cmpl? is compiling? \ cword current compiled word   wordlist constant DEFS wordlist constant KEYS   \ --- Compiling 50 constant WORD# : >>fPAD ( ca u -- ; u < 51 ) PAD 80 blank s" create " PAD swap MOVE s" 1 , DOES> 1 swap +! ;" PAD 57 + swap MOVE WORD# min PAD 7 + swap MOVE ;   : funcmpl ( ca u -- ) >>fPAD current @ DEFS current ! PAD 80 evaluate current ! ;   : >>kPAD ( ca u -- ; ) PAD 80 blank s" : " PAD swap MOVE s" parse-name funcmpl ;" PAD 59 + swap MOVE WORD# min PAD 2 + swap MOVE ;   : keycmpl ( ca u -- ) >>kPAD current @ KEYS current ! PAD 80 evaluate current ! ;   \ --- Interpreter : intp BEGIN parse-name dup WHILE ( ca u ) 2dup KEYS search-wordlist IF execute 2drop ELSE DEFS search-wordlist IF execute THEN THEN REPEAT 2drop ;   : run BEGIN refill WHILE intp REPEAT ;   \ --- Lists&Rings warnings OFF : LIST ( node -- ) ]] BEGIN @ dup WHILE >R [[ ; immediate warnings ON : LOOP-LIST ( -- ) ]] R> REPEAT drop [[ ; immediate   : empty-ring? ( node -- f ) dup @ = ; : RING ( node -- ) ]] dup BEGIN @ 2dup <> WHILE 2>R [[ ; immediate : LOOP-RING ( -- ) ]] 2R> REPEAT 2drop [[ ; immediate   : new-node ( -- node ) here dup , ; : do-link ( node new-node -- ; do link after current node ) over @ over ! swap ! ;   \ --- Sorting.. : nt>freq ( nt -- n ;frequency of uses ) name>int >BODY @ ;   : @maxfreq ( wid -- n ;maximum frequency ) 0 swap cell+ LIST ( max ) I nt>freq 2dup < IF nip ELSE drop THEN LOOP-LIST ;   2 cells constant RING# : rings-vec ( u -- a size ; create vector of rings ) here over 1+ 0 DO new-node drop 0 , LOOP swap RING# * ;   : populate-by ( a wid -- ) cell+ LIST dup I nt>freq RING# * + \ root-node new-node I , \ new-node do-link LOOP-LIST drop ;   \ --- Display TOP : node>nt cell+ @ ;   : .ring ( root-node -- ) 0 swap RING dup 0= IF I node>nt nt>freq . THEN space I node>nt name>string type 1+ LOOP-RING drop cr ;   : .top ( a size n -- ) -rot BOUNDS swap ?DO ( n ) I empty-ring? 0= IF 1- I .ring THEN dup 0= IF drop UNLOOP EXIT THEN [ RING# negate ] LITERAL +LOOP drop ;   : args>top# ( -- n ) 1 arg 2dup 0 0 d<> IF >float IF f>d d>s dup 0= IF drop 4 THEN ELSE 4 THEN ELSE 2drop 4 THEN ;     \ --- KEYS behaviour variable cmpl? cmpl? OFF 2variable cword here WORD# allot 0 cword 2!   current @ KEYS current ! : create cmpl? @ IF cword 2@ keycmpl ELSE parse-name funcmpl THEN ;   : constant cmpl? @ IF cword 2@ keycmpl ELSE parse-name funcmpl THEN ;   : variable parse-name funcmpl ; : value parse-name funcmpl ; : defer parse-name funcmpl ;   : ( BEGIN >in @ [char] ) parse nip >in @ rot - = WHILE refill 0= IF exit THEN REPEAT ; : \ 10 parse 2drop ; : \G 10 parse 2drop ; : S" [char] " parse 2drop ; : ." [char] " parse 2drop ;   : ['] parse-name DEFS search-wordlist IF execute THEN ; : postpone parse-name DEFS search-wordlist IF execute THEN ;   : ; cmpl? OFF ; : : warnings OFF parse-name cword 2@ drop WORD# rot umin dup >R MOVE cword 2@ drop R> cword 2! cword 2@ cmpl? @ IF keycmpl \ `:' inside def. = a defining word ELSE funcmpl THEN cmpl? ON warnings ON ; current !   \ Run, ruuun! stdin ' run execute-parsing-file DEFS @maxfreq rings-vec over DEFS populate-by args>top# .top bye  
http://rosettacode.org/wiki/Gamma_function
Gamma function
Task Implement one algorithm (or more) to compute the Gamma ( Γ {\displaystyle \Gamma } ) function (in the real field only). If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in/library function. The Gamma function can be defined as: Γ ( x ) = ∫ 0 ∞ t x − 1 e − t d t {\displaystyle \Gamma (x)=\displaystyle \int _{0}^{\infty }t^{x-1}e^{-t}dt} This suggests a straightforward (but inefficient) way of computing the Γ {\displaystyle \Gamma } through numerical integration. Better suggested methods: Lanczos approximation Stirling's approximation
#BASIC256
BASIC256
print " x Stirling Lanczos" print for i = 1 to 20 d = i / 10.0 print d; print chr(9); ljust(string(gammaStirling(d)), 13, "0"); print chr(9); ljust(string(gammaLanczos(d)), 13, "0") next i end   function gammaStirling (x) e = exp(1) # e is not predefined in BASIC256 return sqr(2.0 * pi / x) * ((x / e) ^ x) end function   function gammaLanczos (x) dim p = {0.99999999999980993, 676.5203681218851, -1259.1392167224028, 771.32342877765313, -176.61502916214059, 12.507343278686905, -0.13857109526572012, 9.9843695780195716e-6, 1.5056327351493116e-7}   g = 7 if x < 0.5 then return pi / (sin(pi * x) * gammaLanczos(1-x)) x -= 1 a = p[0] t = x + g + 0.5   for i = 1 to 8 a += p[i] / (x + i) next i return sqr(2.0 * pi) * (t ^ (x + 0.5)) * exp(-t) * a end function
http://rosettacode.org/wiki/Galton_box_animation
Galton box animation
Example of a Galton Box at the end of animation. A   Galton device   Sir Francis Galton's device   is also known as a   bean machine,   a   Galton Board,   or a   quincunx. Description of operation In a Galton box, there are a set of pins arranged in a triangular pattern.   A number of balls are dropped so that they fall in line with the top pin, deflecting to the left or the right of the pin.   The ball continues to fall to the left or right of lower pins before arriving at one of the collection points between and to the sides of the bottom row of pins. Eventually the balls are collected into bins at the bottom   (as shown in the image),   the ball column heights in the bins approximate a   bell curve.   Overlaying   Pascal's triangle   onto the pins shows the number of different paths that can be taken to get to each bin. Task Generate an animated simulation of a Galton device. Task requirements   The box should have at least 5 pins on the bottom row.   A solution can use graphics or ASCII animation.   Provide a sample of the output/display such as a screenshot.   There can be one or more balls in flight at the same time.   If multiple balls are in flight, ensure they don't interfere with each other.   A solution should allow users to specify the number of balls, or it should run until full or a preset limit.   Optionally,   display the number of balls.
#Go
Go
package main   import ( "fmt" "math/rand" "time" )   const boxW = 41 // Galton box width const boxH = 37 // Galton box height. const pinsBaseW = 19 // Pins triangle base. const nMaxBalls = 55 // Number of balls.   const centerH = pinsBaseW + (boxW-pinsBaseW*2+1)/2 - 1   const ( empty = ' ' ball = 'o' wall = '|' corner = '+' floor = '-' pin = '.' )   type Ball struct{ x, y int }   func newBall(x, y int) *Ball { if box[y][x] != empty { panic("Tried to create a new ball in a non-empty cell. Program terminated.") } b := Ball{x, y} box[y][x] = ball return &b }   func (b *Ball) doStep() { if b.y <= 0 { return // Reached the bottom of the box. } cell := box[b.y-1][b.x] switch cell { case empty: box[b.y][b.x] = empty b.y-- box[b.y][b.x] = ball case pin: box[b.y][b.x] = empty b.y-- if box[b.y][b.x-1] == empty && box[b.y][b.x+1] == empty { b.x += rand.Intn(2)*2 - 1 box[b.y][b.x] = ball return } else if box[b.y][b.x-1] == empty { b.x++ } else { b.x-- } box[b.y][b.x] = ball default: // It's frozen - it always piles on other balls. } }   type Cell = byte   /* Galton box. Will be printed upside down. */ var box [boxH][boxW]Cell   func initializeBox() { // Set ceiling and floor box[0][0] = corner box[0][boxW-1] = corner for i := 1; i < boxW-1; i++ { box[0][i] = floor } for i := 0; i < boxW; i++ { box[boxH-1][i] = box[0][i] }   // Set walls for r := 1; r < boxH-1; r++ { box[r][0] = wall box[r][boxW-1] = wall }   // Set rest to empty initially for i := 1; i < boxH-1; i++ { for j := 1; j < boxW-1; j++ { box[i][j] = empty } }   // Set pins for nPins := 1; nPins <= pinsBaseW; nPins++ { for p := 0; p < nPins; p++ { box[boxH-2-nPins][centerH+1-nPins+p*2] = pin } } }   func drawBox() { for r := boxH - 1; r >= 0; r-- { for c := 0; c < boxW; c++ { fmt.Printf("%c", box[r][c]) } fmt.Println() } }   func main() { rand.Seed(time.Now().UnixNano()) initializeBox() var balls []*Ball for i := 0; i < nMaxBalls+boxH; i++ { fmt.Println("\nStep", i, ":") if i < nMaxBalls { balls = append(balls, newBall(centerH, boxH-2)) // add ball } drawBox()   // Next step for the simulation. // Frozen balls are kept in balls slice for simplicity for _, b := range balls { b.doStep() } } }
http://rosettacode.org/wiki/Gapful_numbers
Gapful numbers
Numbers   (positive integers expressed in base ten)   that are (evenly) divisible by the number formed by the first and last digit are known as   gapful numbers. Evenly divisible   means divisible with   no   remainder. All   one─   and two─digit   numbers have this property and are trivially excluded.   Only numbers   ≥ 100   will be considered for this Rosetta Code task. Example 187   is a   gapful   number because it is evenly divisible by the number   17   which is formed by the first and last decimal digits of   187. About   7.46%   of positive integers are   gapful. Task   Generate and show all sets of numbers (below) on one line (horizontally) with a title,   here on this page   Show the first   30   gapful numbers   Show the first   15   gapful numbers   ≥          1,000,000   Show the first   10   gapful numbers   ≥   1,000,000,000 Related tasks   Harshad or Niven series.   palindromic gapful numbers.   largest number divisible by its digits. Also see   The OEIS entry:   A108343 gapful numbers.   numbersaplenty gapful numbers
#FreeBASIC
FreeBASIC
  function is_gapful( n as uinteger ) as boolean if n<100 then return false dim as string ns = str(n) dim as uinteger gap = 10*val(mid(ns,1,1)) + val(mid(ns,len(ns),1)) if n mod gap = 0 then return true else return false end function   dim as ulongint i = 100 dim as ushort c print "The first thirty gapful numbers:" while c<30 if is_gapful(i) then c += 1 print i;" "; end if i += 1 wend print : print i = 1000000 : c = 0 print "The first fifteen gapful numbers above 999,999:" while c<15 if is_gapful(i) then c += 1 print i;" "; end if i += 1 wend print : print i = 1000000000 : c = 0 print "The first ten gapful numbers above 999,999,999:" while c<10 if is_gapful(i) then c += 1 print i;" "; end if i += 1 wend print
http://rosettacode.org/wiki/Gaussian_elimination
Gaussian elimination
Task Solve   Ax=b   using Gaussian elimination then backwards substitution. A   being an   n by n   matrix. Also,   x and b   are   n by 1   vectors. To improve accuracy, please use partial pivoting and scaling. See also   the Wikipedia entry:   Gaussian elimination
#Generic
Generic
  generic coordinaat { ecs; uuii;   coordinaat() { ecs=+a;uuii=+a;}   coordinaat(ecs_set,uuii_set) { ecs = ecs_set; uuii=uuii_set;}   operaator<(c) { iph ecs < c.ecs return troo; iph c.ecs < ecs return phals; iph uuii < c.uuii return troo; return phals; }   operaator==(connpair) // eecuuols and not eecuuols deriiu phronn operaator< { iph this < connpair return phals; iph connpair < this return phals; return troo; }   operaator!=(connpair) { iph this < connpair return troo; iph connpair < this return troo; return phals; }   too_string() { return "(" + ecs.too_string() + "," + uuii.too_string() + ")"; }   print() { str = too_string(); str.print(); }   println() { str = too_string(); str.println(); } }   generic nnaatrics { s; // this is a set of coordinaat/ualioo pairs. iteraator; // this field holds an iteraator phor the nnaatrics.   nnaatrics() // no parameters required phor nnaatrics construction. { s = nioo set(); // create a nioo set of coordinaat/ualioo pairs. iteraator = nul; // the iteraator is initially set to nul. }   nnaatrics(copee) // copee the nnaatrics. { s = nioo set(); // create a nioo set of coordinaat/ualioo pairs. iteraator = nul; // the iteraator is initially set to nul.   r = copee.rouus; c = copee.cols; i = 0; uuiil i < r { j = 0; uuiil j < c { this[i,j] = copee[i,j]; j++; } i++; } }   begin { get { return s.begin; } } // property: used to commence manual iteraashon.   end { get { return s.end; } } // property: used to dephiin the end itenn of iteraashon   operaator<(a) // les than operaator is corld bii the avl tree algorithnns { // this operaator innpliis phor instance that you could potenshalee hav sets ou nnaatricss. iph cees < a.cees // connpair the cee sets phurst. return troo; els iph a.cees < cees return phals; els // the cee sets are eecuuol thairphor connpair nnaatrics elennents. { phurst1 = begin; lahst1 = end; phurst2 = a.begin; lahst2 = a.end;   uuiil phurst1 != lahst1 && phurst2 != lahst2 { iph phurst1.daata.ualioo < phurst2.daata.ualioo return troo; els { iph phurst2.daata.ualioo < phurst1.daata.ualioo return phals; els { phurst1 = phurst1.necst; phurst2 = phurst2.necst; } } }   return phals; } }   operaator==(connpair) // eecuuols and not eecuuols deriiu phronn operaator< { iph this < connpair return phals; iph connpair < this return phals; return troo; }   operaator!=(connpair) { iph this < connpair return troo; iph connpair < this return troo; return phals; }     operaator[](cee_a,cee_b) // this is the nnaatrics indexer. { set { trii { s >> nioo cee_ualioo(new coordinaat(cee_a,cee_b)); } catch {} s << nioo cee_ualioo(new coordinaat(nioo integer(cee_a),nioo integer(cee_b)),ualioo); } get { d = s.get(nioo cee_ualioo(new coordinaat(cee_a,cee_b))); return d.ualioo; } }   operaator>>(coordinaat) // this operaator reennoous an elennent phronn the nnaatrics. { s >> nioo cee_ualioo(coordinaat); return this; }   iteraat() // and this is how to iterate on the nnaatrics. { iph iteraator.nul() { iteraator = s.lepht_nnohst; iph iteraator == s.heder return nioo iteraator(phals,nioo nun()); els return nioo iteraator(troo,iteraator.daata.ualioo); } els { iteraator = iteraator.necst;   iph iteraator == s.heder { iteraator = nul; return nioo iteraator(phals,nioo nun()); } els return nioo iteraator(troo,iteraator.daata.ualioo); } }   couunt // this property returns a couunt ou elennents in the nnaatrics. { get { return s.couunt; } }   ennptee // is the nnaatrics ennptee? { get { return s.ennptee; } }     lahst // returns the ualioo of the lahst elennent in the nnaatrics. { get { iph ennptee throuu "ennptee nnaatrics"; els return s.lahst.ualioo; } }   too_string() // conuerts the nnaatrics too aa string { return s.too_string(); }   print() // prints the nnaatrics to the consohl. { out = too_string(); out.print(); }   println() // prints the nnaatrics as a liin too the consohl. { out = too_string(); out.println(); }   cees // return the set ou cees ou the nnaatrics (a set of coordinaats). { get { k = nioo set(); phor e : s k << e.cee; return k; } }   operaator+(p) { ouut = nioo nnaatrics(); phurst1 = begin; lahst1 = end; phurst2 = p.begin; lahst2 = p.end; uuiil phurst1 != lahst1 && phurst2 != lahst2 { ouut[phurst1.daata.cee.ecs,phurst1.daata.cee.uuii] = phurst1.daata.ualioo + phurst2.daata.ualioo; phurst1 = phurst1.necst; phurst2 = phurst2.necst; } return ouut; }   operaator-(p) { ouut = nioo nnaatrics(); phurst1 = begin; lahst1 = end; phurst2 = p.begin; lahst2 = p.end; uuiil phurst1 != lahst1 && phurst2 != lahst2 { ouut[phurst1.daata.cee.ecs,phurst1.daata.cee.uuii] = phurst1.daata.ualioo - phurst2.daata.ualioo; phurst1 = phurst1.necst; phurst2 = phurst2.necst; } return ouut; }   rouus { get { r = +a; phurst1 = begin; lahst1 = end; uuiil phurst1 != lahst1 { iph r < phurst1.daata.cee.ecs r = phurst1.daata.cee.ecs; phurst1 = phurst1.necst; } return r + +b; } }   cols { get { c = +a; phurst1 = begin; lahst1 = end; uuiil phurst1 != lahst1 { iph c < phurst1.daata.cee.uuii c = phurst1.daata.cee.uuii; phurst1 = phurst1.necst; } return c + +b; } }   operaator*(o) { iph cols != o.rouus throw "rouus-cols nnisnnatch"; reesult = nioo nnaatrics(); rouu_couunt = rouus; colunn_couunt = o.cols; loop = cols; i = +a; uuiil i < rouu_couunt { g = +a; uuiil g < colunn_couunt { sunn = +a.a; h = +a; uuiil h < loop { a = this[i, h];   b = o[h, g]; nn = a * b; sunn = sunn + nn; h++; }   reesult[i, g] = sunn;   g++; } i++; } return reesult; }   suuop_rouus(a, b) { c = cols; i = 0; uuiil u < cols { suuop = this[a, i]; this[a, i] = this[b, i]; this[b, i] = suuop; i++; } }   suuop_colunns(a, b) { r = rouus; i = 0; uuiil i < rouus { suuopp = this[i, a]; this[i, a] = this[i, b]; this[i, b] = suuop; i++; } }   transpohs { get { reesult = new nnaatrics();   r = rouus; c = cols; i=0; uuiil i < r { g = 0; uuiil g < c { reesult[g, i] = this[i, g]; g++; } i++; }   return reesult; } }   deternninant { get { rouu_couunt = rouus; colunn_count = cols;   if rouu_couunt != colunn_count throw "not a scuuair nnaatrics";   if rouu_couunt == 0 throw "the nnaatrics is ennptee";   if rouu_couunt == 1 return this[0, 0];   if rouu_couunt == 2 return this[0, 0] * this[1, 1] - this[0, 1] * this[1, 0];   temp = nioo nnaatrics();   det = 0.0; parity = 1.0;   j = 0; uuiil j < rouu_couunt { k = 0; uuiil k < rouu_couunt-1 { skip_col = phals;   l = 0; uuiil l < rouu_couunt-1 { if l == j skip_col = troo;   if skip_col n = l + 1; els n = l;   temp[k, l] = this[k + 1, n]; l++; } k++; }   det = det + parity * this[0, j] * temp.deeternninant;   parity = 0.0 - parity; j++; }   return det; } }   ad_rouu(a, b) { c = cols; i = 0; uuiil i < c { this[a, i] = this[a, i] + this[b, i]; i++; } }   ad_colunn(a, b) { c = rouus; i = 0; uuiil i < c { this[i, a] = this[i, a] + this[i, b]; i++; } }   subtract_rouu(a, b) { c = cols; i = 0; uuiil i < c { this[a, i] = this[a, i] - this[b, i]; i++; } }   subtract_colunn(a, b) { c = rouus; i = 0; uuiil i < c { this[i, a] = this[i, a] - this[i, b]; i++; } }   nnultiplii_rouu(rouu, scalar) { c = cols; i = 0; uuiil i < c { this[rouu, i] = this[rouu, i] * scalar; i++; } }   nnultiplii_colunn(colunn, scalar) { r = rouus; i = 0; uuiil i < r { this[i, colunn] = this[i, colunn] * scalar; i++; } }   diuiid_rouu(rouu, scalar) { c = cols; i = 0; uuiil i < c { this[rouu, i] = this[rouu, i] / scalar; i++; } }   diuiid_colunn(colunn, scalar) { r = rouus; i = 0; uuiil i < r { this[i, colunn] = this[i, colunn] / scalar; i++; } }   connbiin_rouus_ad(a,b,phactor) { c = cols; i = 0; uuiil i < c { this[a, i] = this[a, i] + phactor * this[b, i]; i++; } }   connbiin_rouus_subtract(a,b,phactor) { c = cols; i = 0; uuiil i < c { this[a, i] = this[a, i] - phactor * this[b, i]; i++; } }   connbiin_colunns_ad(a,b,phactor) { r = rouus; i = 0; uuiil i < r { this[i, a] = this[i, a] + phactor * this[i, b]; i++; } }   connbiin_colunns_subtract(a,b,phactor) { r = rouus; i = 0; uuiil i < r { this[i, a] = this[i, a] - phactor * this[i, b]; i++; } }   inuers { get { rouu_couunt = rouus; colunn_couunt = cols;   iph rouu_couunt != colunn_couunt throw "nnatrics not scuuair";   els iph rouu_couunt == 0 throw "ennptee nnatrics";   els iph rouu_couunt == 1 { r = nioo nnaatrics(); r[0, 0] = 1.0 / this[0, 0]; return r; }   gauss = nioo nnaatrics(this);   i = 0; uuiil i < rouu_couunt { j = 0; uuiil j < rouu_couunt { iph i == j   gauss[i, j + rouu_couunt] = 1.0; els gauss[i, j + rouu_couunt] = 0.0; j++; }   i++; }   j = 0; uuiil j < rouu_couunt { iph gauss[j, j] == 0.0 { k = j + 1;   uuiil k < rouu_couunt { if gauss[k, j] != 0.0 {gauss.nnaat.suuop_rouus(j, k); break; } k++; }   if k == rouu_couunt throw "nnatrics is singioolar"; }   phactor = gauss[j, j]; iph phactor != 1.0 gauss.diuiid_rouu(j, phactor);   i = j+1; uuiil i < rouu_couunt { gauss.connbiin_rouus_subtract(i, j, gauss[i, j]); i++; }   j++; }   i = rouu_couunt - 1; uuiil i > 0 { k = i - 1; uuiil k >= 0 { gauss.connbiin_rouus_subtract(k, i, gauss[k, i]); k--; } i--; }   reesult = nioo nnaatrics();   i = 0; uuiil i < rouu_couunt { j = 0; uuiil j < rouu_couunt { reesult[i, j] = gauss[i, j + rouu_couunt]; j++; } i++; }   return reesult; } }   }
http://rosettacode.org/wiki/Gauss-Jordan_matrix_inversion
Gauss-Jordan matrix inversion
Task Invert matrix   A   using Gauss-Jordan method. A   being an   n × n   matrix.
#Lambdatalk
Lambdatalk
  {require lib_matrix}   {M.gaussJordan {M.new [[1,2,3], [4,5,6], [7,8,-9]]}} -> [[-1.722222222222222,0.7777777777777777,-0.05555555555555555], [1.4444444444444444,-0.5555555555555556,0.1111111111111111], [-0.05555555555555555,0.1111111111111111,-0.05555555555555555]]  
http://rosettacode.org/wiki/General_FizzBuzz
General FizzBuzz
Task Write a generalized version of FizzBuzz that works for any list of factors, along with their words. This is basically a "fizzbuzz" implementation where the user supplies the parameters. The user will enter the max number, then they will enter the factors to be calculated along with the corresponding word to be printed. For simplicity's sake, assume the user will input an integer as the max number and 3 factors, each with a word associated with them. For example, given: >20 #This is the maximum number, supplied by the user >3 Fizz #The user now enters the starting factor (3) and the word they want associated with it (Fizz) >5 Buzz #The user now enters the next factor (5) and the word they want associated with it (Buzz) >7 Baxx #The user now enters the next factor (7) and the word they want associated with it (Baxx) In other words: For this example, print the numbers 1 through 20, replacing every multiple of 3 with "Fizz", every multiple of 5 with "Buzz", and every multiple of 7 with "Baxx". In the case where a number is a multiple of at least two factors, print each of the words associated with those factors in the order of least to greatest factor. For instance, the number 15 is a multiple of both 3 and 5; print "FizzBuzz". If the max number was 105 instead of 20, you would print "FizzBuzzBaxx" because it's a multiple of 3, 5, and 7. Output: 1 2 Fizz 4 Buzz Fizz Baxx 8 Fizz Buzz 11 Fizz 13 Baxx FizzBuzz 16 17 Fizz 19 Buzz
#JavaScript
JavaScript
function fizz(d, e) { return function b(a) { return a ? b(a - 1).concat(a) : []; }(e).reduce(function (b, a) { return b + (d.reduce(function (b, c) { return b + (a % c[0] ? "" : c[1]); }, "") || a.toString()) + "\n"; }, ""); }
http://rosettacode.org/wiki/Hailstone_sequence
Hailstone sequence
The Hailstone sequence of numbers can be generated from a starting positive integer,   n   by:   If   n   is     1     then the sequence ends.   If   n   is   even then the next   n   of the sequence   = n/2   If   n   is   odd   then the next   n   of the sequence   = (3 * n) + 1 The (unproven) Collatz conjecture is that the hailstone sequence for any starting number always terminates. This sequence was named by Lothar Collatz in 1937   (or possibly in 1939),   and is also known as (the):   hailstone sequence,   hailstone numbers   3x + 2 mapping,   3n + 1 problem   Collatz sequence   Hasse's algorithm   Kakutani's problem   Syracuse algorithm,   Syracuse problem   Thwaites conjecture   Ulam's problem The hailstone sequence is also known as   hailstone numbers   (because the values are usually subject to multiple descents and ascents like hailstones in a cloud). Task Create a routine to generate the hailstone sequence for a number. Use the routine to show that the hailstone sequence for the number 27 has 112 elements starting with 27, 82, 41, 124 and ending with 8, 4, 2, 1 Show the number less than 100,000 which has the longest hailstone sequence together with that sequence's length.   (But don't show the actual sequence!) See also   xkcd (humourous).   The Notorious Collatz conjecture Terence Tao, UCLA (Presentation, pdf).   The Simplest Math Problem No One Can Solve Veritasium (video, sponsored).
#zkl
zkl
fcn collatz(n,z=L()){ z.append(n); if(n==1) return(z); if(n.isEven) return(self.fcn(n/2,z)); return(self.fcn(n*3+1,z)) }
http://rosettacode.org/wiki/Generate_lower_case_ASCII_alphabet
Generate lower case ASCII alphabet
Task Generate an array, list, lazy sequence, or even an indexable string of all the lower case ASCII characters, from a to z. If the standard library contains such a sequence, show how to access it, but don't fail to show how to generate a similar sequence. For this basic task use a reliable style of coding, a style fit for a very large program, and use strong typing if available. It's bug prone to enumerate all the lowercase characters manually in the code. During code review it's not immediate obvious to spot the bug in a Tcl line like this contained in a page of code: set alpha {a b c d e f g h i j k m n o p q r s t u v w x y z} Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#DUP
DUP
0"abcdefghijklmnopqrstuvwxyz" {store character values of string in cells 0..length of string-1} 26[$][^^-;,1-]# {Loop from 26-26 to 26-0, print the respective cell contents to STDOUT}
http://rosettacode.org/wiki/Generate_lower_case_ASCII_alphabet
Generate lower case ASCII alphabet
Task Generate an array, list, lazy sequence, or even an indexable string of all the lower case ASCII characters, from a to z. If the standard library contains such a sequence, show how to access it, but don't fail to show how to generate a similar sequence. For this basic task use a reliable style of coding, a style fit for a very large program, and use strong typing if available. It's bug prone to enumerate all the lowercase characters manually in the code. During code review it's not immediate obvious to spot the bug in a Tcl line like this contained in a page of code: set alpha {a b c d e f g h i j k m n o p q r s t u v w x y z} Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Dyalect
Dyalect
print << ('a'..'z').ToArray()
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#Onyx
Onyx
`Hello world!\n' print flush
http://rosettacode.org/wiki/Generator/Exponential
Generator/Exponential
A generator is an executable entity (like a function or procedure) that contains code that yields a sequence of values, one at a time, so that each time you call the generator, the next value in the sequence is provided. Generators are often built on top of coroutines or objects so that the internal state of the object is handled “naturally”. Generators are often used in situations where a sequence is potentially infinite, and where it is possible to construct the next value of the sequence with only minimal state. Task Create a function that returns a generation of the m'th powers of the positive integers starting from zero, in order, and without obvious or simple upper limit. (Any upper limit to the generator should not be stated in the source but should be down to factors such as the languages natural integer size limit or computational time/size). Use it to create a generator of:   Squares.   Cubes. Create a new generator that filters all cubes from the generator of squares. Drop the first 20 values from this last generator of filtered results, and then show the next 10 values. Note that this task requires the use of generators in the calculation of the result. Also see Generator
#Lingo
Lingo
squares = script("generator.power").new(2) cubes = script("generator.power").new(3) filter = script("generator.filter").new(squares, cubes) filter.skip(20) res = [] i = 0 repeat while filter.exec(res) i = i + 1 if i>10 then exit repeat put res[1] end repeat
http://rosettacode.org/wiki/Greatest_common_divisor
Greatest common divisor
Greatest common divisor You are encouraged to solve this task according to the task description, using any language you may know. Task Find the greatest common divisor   (GCD)   of two integers. Greatest common divisor   is also known as   greatest common factor (gcf)   and   greatest common measure. Related task   least common multiple. See also   MathWorld entry:   greatest common divisor.   Wikipedia entry:     greatest common divisor.
#Yabasic
Yabasic
sub gcd(u, v) local t   u = int(abs(u)) v = int(abs(v)) while(v) t = u u = v v = mod(t, v) wend return u end sub   print "Greatest common divisor: ", gcd(12345, 9876)
http://rosettacode.org/wiki/Greatest_common_divisor
Greatest common divisor
Greatest common divisor You are encouraged to solve this task according to the task description, using any language you may know. Task Find the greatest common divisor   (GCD)   of two integers. Greatest common divisor   is also known as   greatest common factor (gcf)   and   greatest common measure. Related task   least common multiple. See also   MathWorld entry:   greatest common divisor.   Wikipedia entry:     greatest common divisor.
#Z80_Assembly
Z80 Assembly
; Inputs: a, b ; Outputs: a = gcd(a, b) ; Destroys: c ; Assumes: a and b are positive one-byte integers gcd: cp b ret z ; while a != b   jr c, else ; if a > b   sub b ; a = a - b   jr gcd   else: ld c, a ; Save a ld a, b ; Swap b into a so we can do the subtraction sub c ; b = b - a ld b, a ; Put a and b back where they belong ld a, c   jr gcd
http://rosettacode.org/wiki/Generate_Chess960_starting_position
Generate Chess960 starting position
Chess960 is a variant of chess created by world champion Bobby Fischer. Unlike other variants of the game, Chess960 does not require a different material, but instead relies on a random initial position, with a few constraints: as in the standard chess game, all eight white pawns must be placed on the second rank. White pieces must stand on the first rank as in the standard game, in random column order but with the two following constraints: the bishops must be placed on opposite color squares (i.e. they must be an odd number of spaces apart or there must be an even number of spaces between them) the King must be between two rooks (with any number of other pieces between them all) Black pawns and pieces must be placed respectively on the seventh and eighth ranks, mirroring the white pawns and pieces, just as in the standard game. (That is, their positions are not independently randomized.) With those constraints there are 960 possible starting positions, thus the name of the variant. Task The purpose of this task is to write a program that can randomly generate any one of the 960 Chess960 initial positions. You will show the result as the first rank displayed with Chess symbols in Unicode: ♔♕♖♗♘ or with the letters King Queen Rook Bishop kNight.
#Python
Python
>>> from itertools import permutations >>> pieces = 'KQRrBbNN' >>> starts = {''.join(p).upper() for p in permutations(pieces) if p.index('B') % 2 != p.index('b') % 2 # Bishop constraint and ( p.index('r') < p.index('K') < p.index('R') # King constraint or p.index('R') < p.index('K') < p.index('r') ) } >>> len(starts) 960 >>> starts.pop() 'QNBRNKRB' >>>
http://rosettacode.org/wiki/Function_composition
Function composition
Task Create a function, compose,   whose two arguments   f   and   g,   are both functions with one argument. The result of compose is to be a function of one argument, (lets call the argument   x),   which works like applying function   f   to the result of applying function   g   to   x. Example compose(f, g) (x) = f(g(x)) Reference: Function composition Hint: In some languages, implementing compose correctly requires creating a closure.
#Aime
Aime
compose_i(,,) { ($0)(($1)($2)); }   compose(,) { compose_i.apply($0, $1); }   double(real a) { 2 * a; }   square(real a) { a * a; }   main(void) { o_(compose(square, double)(40), "\n");   0; }
http://rosettacode.org/wiki/Function_composition
Function composition
Task Create a function, compose,   whose two arguments   f   and   g,   are both functions with one argument. The result of compose is to be a function of one argument, (lets call the argument   x),   which works like applying function   f   to the result of applying function   g   to   x. Example compose(f, g) (x) = f(g(x)) Reference: Function composition Hint: In some languages, implementing compose correctly requires creating a closure.
#ALGOL_68
ALGOL 68
MODE F = PROC(REAL)REAL; # ALGOL 68 is strong typed #   # As a procedure for real to real functions # PROC compose = (F f, g)F: (REAL x)REAL: f(g(x));   OP (F,F)F O = compose; # or an OPerator that can be overloaded #   # Example use: # F sin arc sin = compose(sin, arc sin); print((sin arc sin(0.5), (sin O arc sin)(0.5), new line))
http://rosettacode.org/wiki/FTP
FTP
Task Connect to a server, change directory, list its contents and download a file as binary using the FTP protocol. Use passive mode if available.
#Common_Lisp
Common Lisp
(use-package :ftp)   (with-ftp-connection (conn :hostname "ftp.hq.nasa.gov" :passive-ftp-p t) (send-cwd-command conn "/pub/issoutreach/Living in Space Stories (MP3 Files)") (send-list-command conn t) (let ((filename "Gravity in the Brain.mp3")) (retrieve-file conn filename filename :type :binary)))  
http://rosettacode.org/wiki/FTP
FTP
Task Connect to a server, change directory, list its contents and download a file as binary using the FTP protocol. Use passive mode if available.
#Erlang
Erlang
  %%%------------------------------------------------------------------- %%% To execute in shell, Run the following commands:- %%% >c("ftp_example"). %%% >ftp_example:run(). %%%------------------------------------------------------------------- -module(ftp_example).   -export([run/0]).   run() -> Host = "ftp.easynet.fr", Opts = [{mode, passive}], User = "anonymous", Password = "",   Directory = "/debian/", File = "README.html",   %%% Open connection with FTP Server io:format("Opening connection with host ~p ~n", [Host]), {ok, Pid} = ftp:open(Host, Opts),   %%% Login as Anonymous user io:format("Logging in as user ~p ~n", [User]), ftp:user(Pid, User, Password),   %%% Change Directory to "/debian/" io:format("Changing Directory to ~p ~n", [Directory]), ftp:cd(Pid, Directory),   %%% Listing contents of current Directory io:format("Contents of Current Directory ~n"), {ok, Listing} = ftp:ls(Pid), io:format("~p ~n", [Listing]),   %%% Download file "README.html" io:format("Downloading File ~p to current directory ~n", [File]), ftp:recv(Pid, File),   %%% Close connection io:format("Closing connection to FTP Server"), ftp:close(Pid).  
http://rosettacode.org/wiki/Function_prototype
Function prototype
Some languages provide the facility to declare functions and subroutines through the use of function prototyping. Task Demonstrate the methods available for declaring prototypes within the language. The provided solutions should include: An explanation of any placement restrictions for prototype declarations A prototype declaration for a function that does not require arguments A prototype declaration for a function that requires two arguments A prototype declaration for a function that utilizes varargs A prototype declaration for a function that utilizes optional arguments A prototype declaration for a function that utilizes named parameters Example of prototype declarations for subroutines or procedures (if these differ from functions) An explanation and example of any special forms of prototyping not covered by the above Languages that do not provide function prototyping facilities should be omitted from this task.
#Julia
Julia
julia > function mycompare(a, b)::Cint (a < b) ? -1 : ((a > b) ? +1 : 0) end mycompare (generic function with 1 method)  
http://rosettacode.org/wiki/Function_prototype
Function prototype
Some languages provide the facility to declare functions and subroutines through the use of function prototyping. Task Demonstrate the methods available for declaring prototypes within the language. The provided solutions should include: An explanation of any placement restrictions for prototype declarations A prototype declaration for a function that does not require arguments A prototype declaration for a function that requires two arguments A prototype declaration for a function that utilizes varargs A prototype declaration for a function that utilizes optional arguments A prototype declaration for a function that utilizes named parameters Example of prototype declarations for subroutines or procedures (if these differ from functions) An explanation and example of any special forms of prototyping not covered by the above Languages that do not provide function prototyping facilities should be omitted from this task.
#Kotlin
Kotlin
// version 1.0.6   interface MyInterface { fun foo() // no arguments, no return type fun goo(i: Int, j: Int) // two arguments, no return type fun voo(vararg v: Int) // variable number of arguments, no return type fun ooo(o: Int = 1): Int // optional argument with default value and return type Int fun roo(): Int // no arguments with return type Int val poo: Int // read only property of type Int }   abstract class MyAbstractClass { abstract fun afoo() // abstract member function, no arguments or return type abstract var apoo: Int // abstract read/write member property of type Int }   class Derived : MyAbstractClass(), MyInterface { override fun afoo() {} override var apoo: Int = 0   override fun foo() {} override fun goo(i: Int, j: Int) {} override fun voo(vararg v: Int) {} override fun ooo(o: Int): Int = o // can't specify default argument again here but same as in interface override fun roo(): Int = 2 override val poo: Int = 3 }   fun main(args: Array<String>) { val d = Derived() println(d.apoo) println(d.ooo()) // default argument of 1 inferred println(d.roo()) println(d.poo) }
http://rosettacode.org/wiki/Function_definition
Function definition
A function is a body of code that returns a value. The value returned may depend on arguments provided to the function. Task Write a definition of a function called "multiply" that takes two arguments and returns their product. (Argument types should be chosen so as not to distract from showing how functions are created and values returned). Related task   Function prototype
#6502_Assembly
6502 Assembly
MULTIPLY: STX MULN  ; 6502 has no "acc += xreg" instruction, TXA  ; so use a memory address MULLOOP: DEY CLC  ; remember to clear the carry flag before ADC MULN  ; doing addition or subtraction CPY #$01 BNE MULLOOP RTS
http://rosettacode.org/wiki/French_Republican_calendar
French Republican calendar
Write a program to convert dates between the Gregorian calendar and the French Republican calendar. The year 1 of the Republican calendar began on 22 September 1792. There were twelve months (Vendémiaire, Brumaire, Frimaire, Nivôse, Pluviôse, Ventôse, Germinal, Floréal, Prairial, Messidor, Thermidor, and Fructidor) of 30 days each, followed by five intercalary days or Sansculottides (Fête de la vertu / Virtue Day, Fête du génie / Talent Day, Fête du travail / Labour Day, Fête de l'opinion / Opinion Day, and Fête des récompenses / Honours Day). In leap years (the years 3, 7, and 11) a sixth Sansculottide was added: Fête de la Révolution / Revolution Day. As a minimum, your program should give correct results for dates in the range from 1 Vendémiaire 1 = 22 September 1792 to 10 Nivôse 14 = 31 December 1805 (the last day when the Republican calendar was officially in use). If you choose to accept later dates, be aware that there are several different methods (described on the Wikipedia page) about how to determine leap years after the year 14. You should indicate which method you are using. (Because of these different methods, correct programs may sometimes give different results for dates after 1805.) Test your program by converting the following dates both from Gregorian to Republican and from Republican to Gregorian: • 1 Vendémiaire 1 = 22 September 1792 • 1 Prairial 3 = 20 May 1795 • 27 Messidor 7 = 15 July 1799 (Rosetta Stone discovered) • Fête de la Révolution 11 = 23 September 1803 • 10 Nivôse 14 = 31 December 1805
#F.23
F#
  // French Republican Calander: Nigel Galloway. April 16th., 2021 let firstDay=System.DateTime.Parse("22/9/1792") type monthsFRC= Vendemiaire = 0 |Brumaire = 30 |Frimaire = 60 |Nivose = 90 |Pluviose = 120 |Ventose = 150 |Germinal = 180 |Floral = 210 |Prairial = 240 |Messidor = 270 |Thermidor = 300 |Fructidor = 330 |Virtue = 360 |Talent = 361 |Labour = 362 |Opinion = 363 |Honours = 364 |Revolution = 365 type months= January = 1 |February = 2 |March = 3 |April = 4 |May = 5 |June = 6 |July = 7 |August = 8 |September = 9 |October = 10 |November = 11 |December = 12 let frc2Greg n (g:monthsFRC) l=firstDay+System.TimeSpan.FromDays(float((l-1)*365+l/4+(int g)+n-1)) let rec fG n g=let i=match g with 3 |7 |11->366 |_->365 in if n<i then (n,g) else fG(n-i)(g+1) let Greg2FRC n=let n,g=fG((n-firstDay).Days) 1 match n/30,n%30 with (12,n)->(1,enum<monthsFRC>(360+n),g) |(n,l)->(l+1,enum<monthsFRC>(n*30),g) let n=(frc2Greg 1 monthsFRC.Vendemiaire 1) in printfn "%d %s %d -> %d %A %d" 1 "Vendemiaire" 1 n.Day (enum<months> n.Month) n.Year let n=(frc2Greg 27 monthsFRC.Messidor 7) in printfn "%d %s %d -> %d %A %d" 27 "Messidor" 7 n.Day (enum<months> n.Month) n.Year let n=(frc2Greg 1 monthsFRC.Revolution 11) in printfn "%d %s %d -> %d %A %d" 1 "Revolution" 11 n.Day (enum<months> n.Month) n.Year let n=(frc2Greg 10 monthsFRC.Nivose 14) in printfn "%d %s %d -> %d %A %d" 10 "Nivose" 14 n.Day (enum<months> n.Month) n.Year let n,g,l=Greg2FRC(System.DateTime(1792,9,22)) in printfn "%d %s %d -> %d %A %d" 22 "September" 1792 n g l let n,g,l=Greg2FRC(System.DateTime(1799,7,15)) in printfn "%d %s %d -> %d %A %d" 15 "July" 1799 n g l let n,g,l=Greg2FRC(System.DateTime(1803,9,23)) in printfn "%d %s %d -> %d %A %d" 23 "September" 1803 n g l let n,g,l=Greg2FRC(System.DateTime(1805,12,31)) in printfn "%d %s %d -> %d %A %d" 31 "December" 1805 n g l  
http://rosettacode.org/wiki/Fusc_sequence
Fusc sequence
Definitions The   fusc   integer sequence is defined as:   fusc(0) = 0   fusc(1) = 1   for n>1,   the   nth   term is defined as:   if   n   is even;     fusc(n) = fusc(n/2)   if   n   is   odd;     fusc(n) = fusc((n-1)/2)   +   fusc((n+1)/2) Note that MathWorld's definition starts with unity, not zero.   This task will be using the OEIS' version   (above). An observation   fusc(A) = fusc(B) where   A   is some non-negative integer expressed in binary,   and where   B   is the binary value of   A   reversed. Fusc numbers are also known as:   fusc function   (named by Dijkstra, 1982)   Stern's Diatomic series   (although it starts with unity, not zero)   Stern-Brocot sequence   (although it starts with unity, not zero) Task   show the first   61   fusc numbers (starting at zero) in a horizontal format.   show the fusc number (and its index) whose length is greater than any previous fusc number length.   (the length is the number of decimal digits when the fusc number is expressed in base ten.)   show all numbers with commas   (if appropriate).   show all output here. Related task   RosettaCode Stern-Brocot sequence Also see   the MathWorld entry:   Stern's Diatomic Series.   the OEIS entry:   A2487.
#AWK
AWK
  # syntax: GAWK -f FUSC_SEQUENCE.AWK # converted from C BEGIN { for (i=0; i<61; i++) { printf("%d ",fusc(i)) } printf("\n") print("fusc numbers whose length is greater than any previous fusc number length") printf("%9s %9s\n","fusc","index") for (i=0; i<=700000; i++) { f = fusc(i) leng = num_leng(f) if (leng > max_leng) { max_leng = leng printf("%9s %9s\n",commatize(f),commatize(i)) } } exit(0) } function commatize(x, num) { if (x < 0) { return "-" commatize(-x) } x = int(x) num = sprintf("%d.",x) while (num ~ /^[0-9][0-9][0-9][0-9]/) { sub(/[0-9][0-9][0-9][,.]/,",&",num) } sub(/\.$/,"",num) return(num) } function fusc(n) { if (n == 0 || n == 1) { return(n) } else if (n % 2 == 0) { return fusc(n/2) } else { return fusc((n-1)/2) + fusc((n+1)/2) } } function num_leng(n, sum) { sum = 1 while (n > 9) { n = int(n/10) sum++ } return(sum) }  
http://rosettacode.org/wiki/Functional_coverage_tree
Functional coverage tree
Functional coverage is a measure of how much a particular function of a system has been verified as correct. It is used heavily in tracking the completeness of the verification of complex System on Chip (SoC) integrated circuits, where it can also be used to track how well the functional requirements of the system have been verified. This task uses a sub-set of the calculations sometimes used in tracking functional coverage but uses a more familiar(?) scenario. Task Description The head of the clean-up crews for "The Men in a very dark shade of grey when viewed at night" has been tasked with managing the cleansing of two properties after an incident involving aliens. She arranges the task hierarchically with a manager for the crews working on each house who return with a breakdown of how they will report on progress in each house. The overall hierarchy of (sub)tasks is as follows, cleaning house1 bedrooms bathrooms bathroom1 bathroom2 outside lavatory attic kitchen living rooms lounge dining room conservatory playroom basement garage garden house2 upstairs bedrooms suite 1 suite 2 bedroom 3 bedroom 4 bathroom toilet attics groundfloor kitchen living rooms lounge dining room conservatory playroom wet room & toilet garage garden hot tub suite basement cellars wine cellar cinema The head of cleanup knows that her managers will report fractional completion of leaf tasks (tasks with no child tasks of their own), and she knows that she will want to modify the weight of values of completion as she sees fit. Some time into the cleaning, and some coverage reports have come in and she thinks see needs to weight the big house2 60-40 with respect to coverage from house1 She prefers a tabular view of her data where missing weights are assumed to be 1.0 and missing coverage 0.0. NAME_HIERARCHY |WEIGHT |COVERAGE | cleaning | | | house1 |40 | | bedrooms | |0.25 | bathrooms | | | bathroom1 | |0.5 | bathroom2 | | | outside_lavatory | |1 | attic | |0.75 | kitchen | |0.1 | living_rooms | | | lounge | | | dining_room | | | conservatory | | | playroom | |1 | basement | | | garage | | | garden | |0.8 | house2 |60 | | upstairs | | | bedrooms | | | suite_1 | | | suite_2 | | | bedroom_3 | | | bedroom_4 | | | bathroom | | | toilet | | | attics | |0.6 | groundfloor | | | kitchen | | | living_rooms | | | lounge | | | dining_room | | | conservatory | | | playroom | | | wet_room_&_toilet | | | garage | | | garden | |0.9 | hot_tub_suite | |1 | basement | | | cellars | |1 | wine_cellar | |1 | cinema | |0.75 | Calculation The coverage of a node in the tree is calculated as the weighted average of the coverage of its children evaluated bottom-upwards in the tree. The task is to calculate the overall coverage of the cleaning task and display the coverage at all levels of the hierarchy on this page, in a manner that visually shows the hierarchy, weights and coverage of all nodes. Extra Credit After calculating the coverage for all nodes, one can also calculate the additional/delta top level coverage that would occur if any (sub)task were to be fully covered from its current fractional coverage. This is done by multiplying the extra coverage that could be gained 1 − c o v e r a g e {\displaystyle 1-coverage} for any node, by the product of the `powers` of its parent nodes from the top down to the node. The power of a direct child of any parent is given by the power of the parent multiplied by the weight of the child divided by the sum of the weights of all the direct children. The pseudo code would be: method delta_calculation(this, power): sum_of_weights = sum(node.weight for node in children) this.delta = (1 - this.coverage) * power for node in self.children: node.delta_calculation(power * node.weight / sum_of_weights) return this.delta Followed by a call to: top.delta_calculation(power=1) Note: to aid in getting the data into your program you might want to use an alternative, more functional description of the starting data given on the discussion page.
#Python
Python
from itertools import zip_longest     fc2 = '''\ cleaning,, house1,40, bedrooms,,.25 bathrooms,, bathroom1,,.5 bathroom2,, outside_lavatory,,1 attic,,.75 kitchen,,.1 living_rooms,, lounge,, dining_room,, conservatory,, playroom,,1 basement,, garage,, garden,,.8 house2,60, upstairs,, bedrooms,, suite_1,, suite_2,, bedroom_3,, bedroom_4,, bathroom,, toilet,, attics,,.6 groundfloor,, kitchen,, living_rooms,, lounge,, dining_room,, conservatory,, playroom,, wet_room_&_toilet,, garage,, garden,,.9 hot_tub_suite,,1 basement,, cellars,,1 wine_cellar,,1 cinema,,.75   '''   NAME, WT, COV = 0, 1, 2   def right_type(txt): try: return float(txt) except ValueError: return txt   def commas_to_list(the_list, lines, start_indent=0): ''' Output format is a nest of lists and tuples lists are for coverage leaves without children items in the list are name, weight, coverage tuples are 2-tuples for nodes with children. The first element is a list representing the name, weight, coverage of the node (some to be calculated); the second element is a list of child elements which may be 2-tuples or lists as above.   the_list is modified in-place lines must be a generator of successive lines of input like fc2 ''' for n, line in lines: indent = 0 while line.startswith(' ' * (4 * indent)): indent += 1 indent -= 1 fields = [right_type(f) for f in line.strip().split(',')] if indent == start_indent: the_list.append(fields) elif indent > start_indent: lst = [fields] sub = commas_to_list(lst, lines, indent) the_list[-1] = (the_list[-1], lst) if sub not in (None, ['']) : the_list.append(sub) else: return fields if fields else None return None     def pptreefields(lst, indent=0, widths=['%-32s', '%-8g', '%-10g']): ''' Pretty prints the format described from function commas_to_list as a table with names in the first column suitably indented and all columns having a fixed minimum column width. ''' lhs = ' ' * (4 * indent) for item in lst: if type(item) != tuple: name, *rest = item print(widths[0] % (lhs + name), end='|') for width, item in zip_longest(widths[1:len(rest)], rest, fillvalue=widths[-1]): if type(item) == str: width = width[:-1] + 's' print(width % item, end='|') print() else: item, children = item name, *rest = item print(widths[0] % (lhs + name), end='|') for width, item in zip_longest(widths[1:len(rest)], rest, fillvalue=widths[-1]): if type(item) == str: width = width[:-1] + 's' print(width % item, end='|') print() pptreefields(children, indent+1)     def default_field(node_list): node_list[WT] = node_list[WT] if node_list[WT] else 1.0 node_list[COV] = node_list[COV] if node_list[COV] else 0.0   def depth_first(tree, visitor=default_field): for item in tree: if type(item) == tuple: item, children = item depth_first(children, visitor) visitor(item)     def covercalc(tree): ''' Depth first weighted average of coverage ''' sum_covwt, sum_wt = 0, 0 for item in tree: if type(item) == tuple: item, children = item item[COV] = covercalc(children) sum_wt += item[WT] sum_covwt += item[COV] * item[WT] cov = sum_covwt / sum_wt return cov   if __name__ == '__main__': lstc = [] commas_to_list(lstc, ((n, ln) for n, ln in enumerate(fc2.split('\n')))) #pp(lstc, width=1, indent=4, compact=1)   #print('\n\nEXPANDED DEFAULTS\n') depth_first(lstc) #pptreefields(['NAME_HIERARCHY WEIGHT COVERAGE'.split()] + lstc)   print('\n\nTOP COVERAGE = %f\n' % covercalc(lstc)) depth_first(lstc) pptreefields(['NAME_HIERARCHY WEIGHT COVERAGE'.split()] + lstc)
http://rosettacode.org/wiki/Function_frequency
Function frequency
Display - for a program or runtime environment (whatever suits the style of your language) - the top ten most frequently occurring functions (or also identifiers or tokens, if preferred). This is a static analysis: The question is not how often each function is actually executed at runtime, but how often it is used by the programmer. Besides its practical usefulness, the intent of this task is to show how to do self-inspection within the language.
#Go
Go
package main   import ( "fmt" "go/ast" "go/parser" "go/token" "io/ioutil" "os" "sort" )   func main() { if len(os.Args) != 2 { fmt.Println("usage ff <go source filename>") return } src, err := ioutil.ReadFile(os.Args[1]) if err != nil { fmt.Println(err) return } fs := token.NewFileSet() a, err := parser.ParseFile(fs, os.Args[1], src, 0) if err != nil { fmt.Println(err) return } f := fs.File(a.Pos()) m := make(map[string]int) ast.Inspect(a, func(n ast.Node) bool { if ce, ok := n.(*ast.CallExpr); ok { start := f.Offset(ce.Pos()) end := f.Offset(ce.Lparen) m[string(src[start:end])]++ } return true }) cs := make(calls, 0, len(m)) for k, v := range m { cs = append(cs, &call{k, v}) } sort.Sort(cs) for i, c := range cs { fmt.Printf("%-20s %4d\n", c.expr, c.count) if i == 9 { break } } }   type call struct { expr string count int } type calls []*call   func (c calls) Len() int { return len(c) } func (c calls) Swap(i, j int) { c[i], c[j] = c[j], c[i] } func (c calls) Less(i, j int) bool { return c[i].count > c[j].count }
http://rosettacode.org/wiki/Gamma_function
Gamma function
Task Implement one algorithm (or more) to compute the Gamma ( Γ {\displaystyle \Gamma } ) function (in the real field only). If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in/library function. The Gamma function can be defined as: Γ ( x ) = ∫ 0 ∞ t x − 1 e − t d t {\displaystyle \Gamma (x)=\displaystyle \int _{0}^{\infty }t^{x-1}e^{-t}dt} This suggests a straightforward (but inefficient) way of computing the Γ {\displaystyle \Gamma } through numerical integration. Better suggested methods: Lanczos approximation Stirling's approximation
#BBC_BASIC
BBC BASIC
*FLOAT64 INSTALL @lib$+"FNUSING"   FOR x = 0.1 TO 2.05 STEP 0.1 PRINT FNusing("#.#",x), FNusing("##.############", FNgamma(x)) NEXT END   DEF FNgamma(z) = EXP(FNlngamma(z))   DEF FNlngamma(z) LOCAL a, b, i%, lz() DIM lz(6) lz() = 1.000000000190015, 76.18009172947146, -86.50532032941677, \ \ 24.01409824083091, -1.231739572450155, 0.0012086509738662, -0.000005395239385 IF z < 0.5 THEN = LN(PI / SIN(PI * z)) - FNlngamma(1.0 - z) z -= 1.0 b = z + 5.5 a = lz(0) FOR i% = 1 TO 6 a += lz(i%) / (z + i%) NEXT = (LNSQR(2*PI) + LN(a) - b) + LN(b) * (z+0.5)
http://rosettacode.org/wiki/Galton_box_animation
Galton box animation
Example of a Galton Box at the end of animation. A   Galton device   Sir Francis Galton's device   is also known as a   bean machine,   a   Galton Board,   or a   quincunx. Description of operation In a Galton box, there are a set of pins arranged in a triangular pattern.   A number of balls are dropped so that they fall in line with the top pin, deflecting to the left or the right of the pin.   The ball continues to fall to the left or right of lower pins before arriving at one of the collection points between and to the sides of the bottom row of pins. Eventually the balls are collected into bins at the bottom   (as shown in the image),   the ball column heights in the bins approximate a   bell curve.   Overlaying   Pascal's triangle   onto the pins shows the number of different paths that can be taken to get to each bin. Task Generate an animated simulation of a Galton device. Task requirements   The box should have at least 5 pins on the bottom row.   A solution can use graphics or ASCII animation.   Provide a sample of the output/display such as a screenshot.   There can be one or more balls in flight at the same time.   If multiple balls are in flight, ensure they don't interfere with each other.   A solution should allow users to specify the number of balls, or it should run until full or a preset limit.   Optionally,   display the number of balls.
#Haskell
Haskell
import Data.Map hiding (map, filter) import Graphics.Gloss import Control.Monad.Random   data Ball = Ball { position :: (Int, Int), turns :: [Int] }   type World = ( Int -- number of rows of pins , [Ball] -- sequence of balls , Map Int Int ) -- counting bins   updateWorld :: World -> World updateWorld (nRows, balls, bins) | y < -nRows-5 = (nRows, map update bs, bins <+> x) | otherwise = (nRows, map update balls, bins) where (Ball (x,y) _) : bs = balls   b <+> x = unionWith (+) b (singleton x 1)   update (Ball (x,y) turns) | -nRows <= y && y < 0 = Ball (x + head turns, y - 1) (tail turns) | otherwise = Ball (x, y - 1) turns   drawWorld :: World -> Picture drawWorld (nRows, balls, bins) = pictures [ color red ballsP , color black binsP , color blue pinsP ] where ballsP = foldMap (disk 1) $ takeWhile ((3 >).snd) $ map position balls binsP = foldMapWithKey drawBin bins pinsP = foldMap (disk 0.2) $ [1..nRows] >>= \i -> [1..i] >>= \j -> [(2*j-i-1, -i-1)]   disk r pos = trans pos $ circleSolid (r*10) drawBin x h = trans (x,-nRows-7) $ rectangleUpperSolid 20 (-fromIntegral h) trans (x,y) = Translate (20 * fromIntegral x) (20 * fromIntegral y)   startSimulation :: Int -> [Ball] -> IO () startSimulation nRows balls = simulate display white 50 world drawWorld update where display = InWindow "Galton box" (400, 400) (0, 0) world = (nRows, balls, empty) update _ _ = updateWorld   main = evalRandIO balls >>= startSimulation 10 where balls = mapM makeBall [1..] makeBall y = Ball (0, y) <$> randomTurns randomTurns = filter (/=0) <$> getRandomRs (-1, 1)
http://rosettacode.org/wiki/Gapful_numbers
Gapful numbers
Numbers   (positive integers expressed in base ten)   that are (evenly) divisible by the number formed by the first and last digit are known as   gapful numbers. Evenly divisible   means divisible with   no   remainder. All   one─   and two─digit   numbers have this property and are trivially excluded.   Only numbers   ≥ 100   will be considered for this Rosetta Code task. Example 187   is a   gapful   number because it is evenly divisible by the number   17   which is formed by the first and last decimal digits of   187. About   7.46%   of positive integers are   gapful. Task   Generate and show all sets of numbers (below) on one line (horizontally) with a title,   here on this page   Show the first   30   gapful numbers   Show the first   15   gapful numbers   ≥          1,000,000   Show the first   10   gapful numbers   ≥   1,000,000,000 Related tasks   Harshad or Niven series.   palindromic gapful numbers.   largest number divisible by its digits. Also see   The OEIS entry:   A108343 gapful numbers.   numbersaplenty gapful numbers
#Frink
Frink
  // Create function to calculate gapful number gapful[num,totalCounter] := { // Display a line explaining the current calculation. println["First $totalCounter gapful numbers over $num:"] // Start a counter to compare with the total count. counter = 0 while counter < totalCounter { numStr = toString[num] // Convert the integer to a string gapfulNumStr = left[numStr,1] + right[numStr,1] // Concatenate the first and last character of the number to form a two digit number gapfulNumInt = parseInt[gapfulNumStr] // Turn the concatenated string back into an integer. // If the concatenated two digit integer divides into the current num variable with no remainder, print it to the list and increase our counter if num mod gapfulNumInt == 0 { print[numStr + " "] counter = counter + 1 } // Increase the current number for the next cycle. num = num + 1 } println[] // Linkbreak }   // Print the first 30 gapful numbers over 100, the top 15 over 1,000,000 and the first 10 over 1,000,000,000. gapful[100,30] gapful[1000000,15] gapful[1000000000,10]  
http://rosettacode.org/wiki/Gapful_numbers
Gapful numbers
Numbers   (positive integers expressed in base ten)   that are (evenly) divisible by the number formed by the first and last digit are known as   gapful numbers. Evenly divisible   means divisible with   no   remainder. All   one─   and two─digit   numbers have this property and are trivially excluded.   Only numbers   ≥ 100   will be considered for this Rosetta Code task. Example 187   is a   gapful   number because it is evenly divisible by the number   17   which is formed by the first and last decimal digits of   187. About   7.46%   of positive integers are   gapful. Task   Generate and show all sets of numbers (below) on one line (horizontally) with a title,   here on this page   Show the first   30   gapful numbers   Show the first   15   gapful numbers   ≥          1,000,000   Show the first   10   gapful numbers   ≥   1,000,000,000 Related tasks   Harshad or Niven series.   palindromic gapful numbers.   largest number divisible by its digits. Also see   The OEIS entry:   A108343 gapful numbers.   numbersaplenty gapful numbers
#F.C5.8Drmul.C3.A6
Fōrmulæ
package main   import "fmt"   func commatize(n uint64) string { s := fmt.Sprintf("%d", n) le := len(s) for i := le - 3; i >= 1; i -= 3 { s = s[0:i] + "," + s[i:] } return s }   func main() { starts := []uint64{1e2, 1e6, 1e7, 1e9, 7123} counts := []int{30, 15, 15, 10, 25} for i := 0; i < len(starts); i++ { count := 0 j := starts[i] pow := uint64(100) for { if j < pow*10 { break } pow *= 10 } fmt.Printf("First %d gapful numbers starting at %s:\n", counts[i], commatize(starts[i])) for count < counts[i] { fl := (j/pow)*10 + (j % 10) if j%fl == 0 { fmt.Printf("%d ", j) count++ } j++ if j >= 10*pow { pow *= 10 } } fmt.Println("\n") } }
http://rosettacode.org/wiki/Gaussian_elimination
Gaussian elimination
Task Solve   Ax=b   using Gaussian elimination then backwards substitution. A   being an   n by n   matrix. Also,   x and b   are   n by 1   vectors. To improve accuracy, please use partial pivoting and scaling. See also   the Wikipedia entry:   Gaussian elimination
#Go
Go
package main   import ( "errors" "fmt" "log" "math" )   type testCase struct { a [][]float64 b []float64 x []float64 }   var tc = testCase{ // common RC example. Result x computed with rational arithmetic then // converted to float64, and so should be about as close to correct as // float64 represention allows. a: [][]float64{ {1.00, 0.00, 0.00, 0.00, 0.00, 0.00}, {1.00, 0.63, 0.39, 0.25, 0.16, 0.10}, {1.00, 1.26, 1.58, 1.98, 2.49, 3.13}, {1.00, 1.88, 3.55, 6.70, 12.62, 23.80}, {1.00, 2.51, 6.32, 15.88, 39.90, 100.28}, {1.00, 3.14, 9.87, 31.01, 97.41, 306.02}}, b: []float64{-0.01, 0.61, 0.91, 0.99, 0.60, 0.02}, x: []float64{-0.01, 1.602790394502114, -1.6132030599055613, 1.2454941213714368, -0.4909897195846576, 0.065760696175232}, }   // result from above test case turns out to be correct to this tolerance. const ε = 1e-13   func main() { x, err := GaussPartial(tc.a, tc.b) if err != nil { log.Fatal(err) } fmt.Println(x) for i, xi := range x { if math.Abs(tc.x[i]-xi) > ε { log.Println("out of tolerance") log.Fatal("expected", tc.x) } } }   func GaussPartial(a0 [][]float64, b0 []float64) ([]float64, error) { // make augmented matrix m := len(b0) a := make([][]float64, m) for i, ai := range a0 { row := make([]float64, m+1) copy(row, ai) row[m] = b0[i] a[i] = row } // WP algorithm from Gaussian elimination page // produces row-eschelon form for k := range a { // Find pivot for column k: iMax := k max := math.Abs(a[k][k]) for i := k + 1; i < m; i++ { if abs := math.Abs(a[i][k]); abs > max { iMax = i max = abs } } if a[iMax][k] == 0 { return nil, errors.New("singular") } // swap rows(k, i_max) a[k], a[iMax] = a[iMax], a[k] // Do for all rows below pivot: for i := k + 1; i < m; i++ { // Do for all remaining elements in current row: for j := k + 1; j <= m; j++ { a[i][j] -= a[k][j] * (a[i][k] / a[k][k]) } // Fill lower triangular matrix with zeros: a[i][k] = 0 } } // end of WP algorithm. // now back substitute to get result. x := make([]float64, m) for i := m - 1; i >= 0; i-- { x[i] = a[i][m] for j := i + 1; j < m; j++ { x[i] -= a[i][j] * x[j] } x[i] /= a[i][i] } return x, nil }
http://rosettacode.org/wiki/Gauss-Jordan_matrix_inversion
Gauss-Jordan matrix inversion
Task Invert matrix   A   using Gauss-Jordan method. A   being an   n × n   matrix.
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
a = N@{{1, 7, 5, 0}, {5, 8, 6, 9}, {2, 1, 6, 4}, {8, 1, 2, 4}}; elimmat = RowReduce[Join[a, IdentityMatrix[Length[a]], 2]]; inv = elimmat[[All, -Length[a] ;;]]
http://rosettacode.org/wiki/General_FizzBuzz
General FizzBuzz
Task Write a generalized version of FizzBuzz that works for any list of factors, along with their words. This is basically a "fizzbuzz" implementation where the user supplies the parameters. The user will enter the max number, then they will enter the factors to be calculated along with the corresponding word to be printed. For simplicity's sake, assume the user will input an integer as the max number and 3 factors, each with a word associated with them. For example, given: >20 #This is the maximum number, supplied by the user >3 Fizz #The user now enters the starting factor (3) and the word they want associated with it (Fizz) >5 Buzz #The user now enters the next factor (5) and the word they want associated with it (Buzz) >7 Baxx #The user now enters the next factor (7) and the word they want associated with it (Baxx) In other words: For this example, print the numbers 1 through 20, replacing every multiple of 3 with "Fizz", every multiple of 5 with "Buzz", and every multiple of 7 with "Baxx". In the case where a number is a multiple of at least two factors, print each of the words associated with those factors in the order of least to greatest factor. For instance, the number 15 is a multiple of both 3 and 5; print "FizzBuzz". If the max number was 105 instead of 20, you would print "FizzBuzzBaxx" because it's a multiple of 3, 5, and 7. Output: 1 2 Fizz 4 Buzz Fizz Baxx 8 Fizz Buzz 11 Fizz 13 Baxx FizzBuzz 16 17 Fizz 19 Buzz
#Julia
Julia
function fizzbuzz(triggers :: Vector{Tuple{Int, ASCIIString}}, upper :: Int) for i = 1 : upper triggered = false   for trigger in triggers if i % trigger[1] == 0 triggered = true print(trigger[2]) end end    !triggered && print(i) println() end end   print("Enter upper limit:\n> ") upper = parse(Int, readline())   triggers = Tuple{Int, ASCIIString}[] print("Enter factor/string pairs (space delimited; ^D when done):\n> ") while (r = readline()) != "" input = split(r) push!(triggers, (parse(Int, input[1]), input[2])) print("> ") end   println("EOF\n") fizzbuzz(triggers, upper)
http://rosettacode.org/wiki/General_FizzBuzz
General FizzBuzz
Task Write a generalized version of FizzBuzz that works for any list of factors, along with their words. This is basically a "fizzbuzz" implementation where the user supplies the parameters. The user will enter the max number, then they will enter the factors to be calculated along with the corresponding word to be printed. For simplicity's sake, assume the user will input an integer as the max number and 3 factors, each with a word associated with them. For example, given: >20 #This is the maximum number, supplied by the user >3 Fizz #The user now enters the starting factor (3) and the word they want associated with it (Fizz) >5 Buzz #The user now enters the next factor (5) and the word they want associated with it (Buzz) >7 Baxx #The user now enters the next factor (7) and the word they want associated with it (Baxx) In other words: For this example, print the numbers 1 through 20, replacing every multiple of 3 with "Fizz", every multiple of 5 with "Buzz", and every multiple of 7 with "Baxx". In the case where a number is a multiple of at least two factors, print each of the words associated with those factors in the order of least to greatest factor. For instance, the number 15 is a multiple of both 3 and 5; print "FizzBuzz". If the max number was 105 instead of 20, you would print "FizzBuzzBaxx" because it's a multiple of 3, 5, and 7. Output: 1 2 Fizz 4 Buzz Fizz Baxx 8 Fizz Buzz 11 Fizz 13 Baxx FizzBuzz 16 17 Fizz 19 Buzz
#Kotlin
Kotlin
fun main(args: Array<String>) {   //Read the maximum number, set to 0 if it couldn't be read val max = readLine()?.toInt() ?: 0 val words = mutableMapOf<Int, String>()   //Read input three times for a factor and a word (1..3).forEach { readLine()?.let { val tokens = it.split(' ') words.put(tokens[0].toInt(), tokens[1]) } }   //Sort the words so they will be output in arithmetic order val sortedWords = words.toSortedMap()   //Find the words with matching factors and print them, print the number if no factors match for (i in 1..max) { val wordsToPrint = sortedWords.filter { i % it.key == 0 }.map { it.value } if (wordsToPrint.isNotEmpty()) { wordsToPrint.forEach { print(it) } println() } else println(i) } }
http://rosettacode.org/wiki/Hailstone_sequence
Hailstone sequence
The Hailstone sequence of numbers can be generated from a starting positive integer,   n   by:   If   n   is     1     then the sequence ends.   If   n   is   even then the next   n   of the sequence   = n/2   If   n   is   odd   then the next   n   of the sequence   = (3 * n) + 1 The (unproven) Collatz conjecture is that the hailstone sequence for any starting number always terminates. This sequence was named by Lothar Collatz in 1937   (or possibly in 1939),   and is also known as (the):   hailstone sequence,   hailstone numbers   3x + 2 mapping,   3n + 1 problem   Collatz sequence   Hasse's algorithm   Kakutani's problem   Syracuse algorithm,   Syracuse problem   Thwaites conjecture   Ulam's problem The hailstone sequence is also known as   hailstone numbers   (because the values are usually subject to multiple descents and ascents like hailstones in a cloud). Task Create a routine to generate the hailstone sequence for a number. Use the routine to show that the hailstone sequence for the number 27 has 112 elements starting with 27, 82, 41, 124 and ending with 8, 4, 2, 1 Show the number less than 100,000 which has the longest hailstone sequence together with that sequence's length.   (But don't show the actual sequence!) See also   xkcd (humourous).   The Notorious Collatz conjecture Terence Tao, UCLA (Presentation, pdf).   The Simplest Math Problem No One Can Solve Veritasium (video, sponsored).
#ZX_Spectrum_Basic
ZX Spectrum Basic
10 LET n=27: LET s=1 20 GO SUB 1000 30 PRINT '"Sequence length = ";seqlen 40 LET maxlen=0: LET s=0 50 FOR m=2 TO 100000 60 LET n=m 70 GO SUB 1000 80 IF seqlen>maxlen THEN LET maxlen=seqlen: LET maxnum=m 90 NEXT m 100 PRINT "The number with the longest hailstone sequence is ";maxnum 110 PRINT "Its sequence length is ";maxlen 120 STOP 1000 REM Hailstone 1010 LET l=0 1020 IF s THEN PRINT n;" "; 1030 IF n=1 THEN LET seqlen=l+1: RETURN 1040 IF FN m(n,2)=0 THEN LET n=INT (n/2): GO TO 1060 1050 LET n=3*n+1 1060 LET l=l+1 1070 GO TO 1020 2000 DEF FN m(a,b)=a-INT (a/b)*b
http://rosettacode.org/wiki/Generate_lower_case_ASCII_alphabet
Generate lower case ASCII alphabet
Task Generate an array, list, lazy sequence, or even an indexable string of all the lower case ASCII characters, from a to z. If the standard library contains such a sequence, show how to access it, but don't fail to show how to generate a similar sequence. For this basic task use a reliable style of coding, a style fit for a very large program, and use strong typing if available. It's bug prone to enumerate all the lowercase characters manually in the code. During code review it's not immediate obvious to spot the bug in a Tcl line like this contained in a page of code: set alpha {a b c d e f g h i j k m n o p q r s t u v w x y z} Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#EchoLisp
EchoLisp
  ;; 1) (define \a (first (string->unicode "a"))) (for/list ((i 25)) (unicode->string (+ i \a))) → (a b c d e f g h i j k l m n o p q r s t u v w x y)   ;;2) using a sequence (lib 'sequences)   (take ["a" .. "z"] 26) → (a b c d e f g h i j k l m n o p q r s t u v w x y z)   ; or (for/string ((letter ["a" .. "z"])) letter) → abcdefghijklmnopqrstuvwxyz  
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#OOC
OOC
main: func { "Hello world!" println() }
http://rosettacode.org/wiki/Generator/Exponential
Generator/Exponential
A generator is an executable entity (like a function or procedure) that contains code that yields a sequence of values, one at a time, so that each time you call the generator, the next value in the sequence is provided. Generators are often built on top of coroutines or objects so that the internal state of the object is handled “naturally”. Generators are often used in situations where a sequence is potentially infinite, and where it is possible to construct the next value of the sequence with only minimal state. Task Create a function that returns a generation of the m'th powers of the positive integers starting from zero, in order, and without obvious or simple upper limit. (Any upper limit to the generator should not be stated in the source but should be down to factors such as the languages natural integer size limit or computational time/size). Use it to create a generator of:   Squares.   Cubes. Create a new generator that filters all cubes from the generator of squares. Drop the first 20 values from this last generator of filtered results, and then show the next 10 values. Note that this task requires the use of generators in the calculation of the result. Also see Generator
#Lua
Lua
  --could be done with a coroutine, but a simple closure works just as well. local function powgen(m) local count = 0 return function() count = count + 1 return count^m end end   local squares = powgen(2) local cubes = powgen(3)   local cowrap,coyield = coroutine.wrap, coroutine.yield   local function filter(f,g) return cowrap(function() local ff,gg = f(), g() while true do if ff == gg then ff,gg = f(), g() elseif ff < gg then coyield(ff) ff = f() else gg = g() end end end) end   filter = filter(squares,cubes)   for i = 1,30 do local result = filter() if i > 20 then print(result) end end  
http://rosettacode.org/wiki/Greatest_common_divisor
Greatest common divisor
Greatest common divisor You are encouraged to solve this task according to the task description, using any language you may know. Task Find the greatest common divisor   (GCD)   of two integers. Greatest common divisor   is also known as   greatest common factor (gcf)   and   greatest common measure. Related task   least common multiple. See also   MathWorld entry:   greatest common divisor.   Wikipedia entry:     greatest common divisor.
#zkl
zkl
(123456789).gcd(987654321) //-->9
http://rosettacode.org/wiki/Greatest_common_divisor
Greatest common divisor
Greatest common divisor You are encouraged to solve this task according to the task description, using any language you may know. Task Find the greatest common divisor   (GCD)   of two integers. Greatest common divisor   is also known as   greatest common factor (gcf)   and   greatest common measure. Related task   least common multiple. See also   MathWorld entry:   greatest common divisor.   Wikipedia entry:     greatest common divisor.
#ZX_Spectrum_Basic
ZX Spectrum Basic
10 FOR n=1 TO 3 20 READ a,b 30 PRINT "GCD of ";a;" and ";b;" = "; 40 GO SUB 70 50 NEXT n 60 STOP 70 IF b=0 THEN PRINT ABS (a): RETURN 80 LET c=a: LET a=b: LET b=FN m(c,b): GO TO 70 90 DEF FN m(a,b)=a-INT (a/b)*b 100 DATA 12,16,22,33,45,67
http://rosettacode.org/wiki/Generate_Chess960_starting_position
Generate Chess960 starting position
Chess960 is a variant of chess created by world champion Bobby Fischer. Unlike other variants of the game, Chess960 does not require a different material, but instead relies on a random initial position, with a few constraints: as in the standard chess game, all eight white pawns must be placed on the second rank. White pieces must stand on the first rank as in the standard game, in random column order but with the two following constraints: the bishops must be placed on opposite color squares (i.e. they must be an odd number of spaces apart or there must be an even number of spaces between them) the King must be between two rooks (with any number of other pieces between them all) Black pawns and pieces must be placed respectively on the seventh and eighth ranks, mirroring the white pawns and pieces, just as in the standard game. (That is, their positions are not independently randomized.) With those constraints there are 960 possible starting positions, thus the name of the variant. Task The purpose of this task is to write a program that can randomly generate any one of the 960 Chess960 initial positions. You will show the result as the first rank displayed with Chess symbols in Unicode: ♔♕♖♗♘ or with the letters King Queen Rook Bishop kNight.
#R
R
  pieces <- c("R","B","N","Q","K","N","B","R")   generateFirstRank <- function() { attempt <- paste0(sample(pieces), collapse = "") while (!check_position(attempt)) { attempt <- paste0(sample(pieces), collapse = "") } return(attempt) }   check_position <- function(position) { if (regexpr('.*R.*K.*R.*', position) == -1) return(FALSE) if (regexpr('.*B(..|....|......|)B.*', position) == -1) return(FALSE) TRUE }   convert_to_unicode <- function(s) { s <- sub("K","\u2654", s) s <- sub("Q","\u2655", s) s <- gsub("R","\u2656", s) s <- gsub("B","\u2657", s) s <- gsub("N","\u2658", s) }   cat(convert_to_unicode(generateFirstRank()), "\n")  
http://rosettacode.org/wiki/Function_composition
Function composition
Task Create a function, compose,   whose two arguments   f   and   g,   are both functions with one argument. The result of compose is to be a function of one argument, (lets call the argument   x),   which works like applying function   f   to the result of applying function   g   to   x. Example compose(f, g) (x) = f(g(x)) Reference: Function composition Hint: In some languages, implementing compose correctly requires creating a closure.
#AntLang
AntLang
/Apply g to exactly one argument compose1: {f: x; g: y; {f[g[x]]}} /Extra: apply to multiple arguments compose: {f: x; g: y; {f[g apply args]}}
http://rosettacode.org/wiki/Function_composition
Function composition
Task Create a function, compose,   whose two arguments   f   and   g,   are both functions with one argument. The result of compose is to be a function of one argument, (lets call the argument   x),   which works like applying function   f   to the result of applying function   g   to   x. Example compose(f, g) (x) = f(g(x)) Reference: Function composition Hint: In some languages, implementing compose correctly requires creating a closure.
#AppleScript
AppleScript
-- Compose two functions where each function is -- a script object with a call(x) handler. on compose(f, g) script on call(x) f's call(g's call(x)) end call end script end compose   script sqrt on call(x) x ^ 0.5 end call end script   script twice on call(x) 2 * x end call end script   compose(sqrt, twice)'s call(32) -- Result: 8.0
http://rosettacode.org/wiki/Fractran
Fractran
FRACTRAN is a Turing-complete esoteric programming language invented by the mathematician John Horton Conway. A FRACTRAN program is an ordered list of positive fractions P = ( f 1 , f 2 , … , f m ) {\displaystyle P=(f_{1},f_{2},\ldots ,f_{m})} , together with an initial positive integer input n {\displaystyle n} . The program is run by updating the integer n {\displaystyle n} as follows: for the first fraction, f i {\displaystyle f_{i}} , in the list for which n f i {\displaystyle nf_{i}} is an integer, replace n {\displaystyle n} with n f i {\displaystyle nf_{i}}  ; repeat this rule until no fraction in the list produces an integer when multiplied by n {\displaystyle n} , then halt. Conway gave a program for primes in FRACTRAN: 17 / 91 {\displaystyle 17/91} , 78 / 85 {\displaystyle 78/85} , 19 / 51 {\displaystyle 19/51} , 23 / 38 {\displaystyle 23/38} , 29 / 33 {\displaystyle 29/33} , 77 / 29 {\displaystyle 77/29} , 95 / 23 {\displaystyle 95/23} , 77 / 19 {\displaystyle 77/19} , 1 / 17 {\displaystyle 1/17} , 11 / 13 {\displaystyle 11/13} , 13 / 11 {\displaystyle 13/11} , 15 / 14 {\displaystyle 15/14} , 15 / 2 {\displaystyle 15/2} , 55 / 1 {\displaystyle 55/1} Starting with n = 2 {\displaystyle n=2} , this FRACTRAN program will change n {\displaystyle n} to 15 = 2 × ( 15 / 2 ) {\displaystyle 15=2\times (15/2)} , then 825 = 15 × ( 55 / 1 ) {\displaystyle 825=15\times (55/1)} , generating the following sequence of integers: 2 {\displaystyle 2} , 15 {\displaystyle 15} , 825 {\displaystyle 825} , 725 {\displaystyle 725} , 1925 {\displaystyle 1925} , 2275 {\displaystyle 2275} , 425 {\displaystyle 425} , 390 {\displaystyle 390} , 330 {\displaystyle 330} , 290 {\displaystyle 290} , 770 {\displaystyle 770} , … {\displaystyle \ldots } After 2, this sequence contains the following powers of 2: 2 2 = 4 {\displaystyle 2^{2}=4} , 2 3 = 8 {\displaystyle 2^{3}=8} , 2 5 = 32 {\displaystyle 2^{5}=32} , 2 7 = 128 {\displaystyle 2^{7}=128} , 2 11 = 2048 {\displaystyle 2^{11}=2048} , 2 13 = 8192 {\displaystyle 2^{13}=8192} , 2 17 = 131072 {\displaystyle 2^{17}=131072} , 2 19 = 524288 {\displaystyle 2^{19}=524288} , … {\displaystyle \ldots } which are the prime powers of 2. Task Write a program that reads a list of fractions in a natural format from the keyboard or from a string, to parse it into a sequence of fractions (i.e. two integers), and runs the FRACTRAN starting from a provided integer, writing the result at each step. It is also required that the number of steps is limited (by a parameter easy to find). Extra credit Use this program to derive the first 20 or so prime numbers. See also For more on how to program FRACTRAN as a universal programming language, see: J. H. Conway (1987). Fractran: A Simple Universal Programming Language for Arithmetic. In: Open Problems in Communication and Computation, pages 4–26. Springer. J. H. Conway (2010). "FRACTRAN: A simple universal programming language for arithmetic". In Jeffrey C. Lagarias. The Ultimate Challenge: the 3x+1 problem. American Mathematical Society. pp. 249–264. ISBN 978-0-8218-4940-8. Zbl 1216.68068. Number Pathology: Fractran by Mark C. Chu-Carroll; October 27, 2006.
#11l
11l
F fractran(prog, =val, limit) V fracts = prog.split(‘ ’).map(p -> p.split(‘/’).map(i -> Int(i))) [Float] r L(n) 0 .< limit r [+]= val L(p) fracts I val % p[1] == 0 val = p[0] * val / p[1] L.break R r   print(fractran(‘17/91 78/85 19/51 23/38 29/33 77/29 95/23 77/19 1/17 11/13 13/11 15/14 15/2 55/1’, 2, 15))
http://rosettacode.org/wiki/FTP
FTP
Task Connect to a server, change directory, list its contents and download a file as binary using the FTP protocol. Use passive mode if available.
#Go
Go
package main   import ( "fmt" "io" "log" "os"   "github.com/stacktic/ftp" )   func main() { // Hard-coded demonstration values const ( hostport = "localhost:21" username = "anonymous" password = "anonymous" dir = "pub" file = "somefile.bin" )   conn, err := ftp.Connect(hostport) if err != nil { log.Fatal(err) } defer conn.Quit() fmt.Println(conn)   if err = conn.Login(username, password); err != nil { log.Fatal(err) } if err = conn.ChangeDir(dir); err != nil { log.Fatal(err) } fmt.Println(conn.CurrentDir()) files, err := conn.List(".") if err != nil { log.Fatal(err) } for _, f := range files { fmt.Printf("%v %12d %v %v\n", f.Time, f.Size, f.Type, f.Name) }   r, err := conn.Retr(file) if err != nil { log.Fatal(err) } defer r.Close()   f, err := os.Create(file) if err != nil { log.Fatal(err) } defer f.Close()   n, err := io.Copy(f, r) if err != nil { log.Fatal(err) }   fmt.Println("Wrote", n, "bytes to", file) }
http://rosettacode.org/wiki/FTP
FTP
Task Connect to a server, change directory, list its contents and download a file as binary using the FTP protocol. Use passive mode if available.
#Groovy
Groovy
  @Grab(group='commons-net', module='commons-net', version='2.0') import org.apache.commons.net.ftp.FTPClient   println("About to connect...."); new FTPClient().with { connect "ftp.easynet.fr" enterLocalPassiveMode() login "anonymous", "[email protected]" changeWorkingDirectory "/debian/" def incomingFile = new File("README.html") incomingFile.withOutputStream { ostream -> retrieveFile "README.html", ostream } disconnect() } println(" ...Done.");  
http://rosettacode.org/wiki/Function_prototype
Function prototype
Some languages provide the facility to declare functions and subroutines through the use of function prototyping. Task Demonstrate the methods available for declaring prototypes within the language. The provided solutions should include: An explanation of any placement restrictions for prototype declarations A prototype declaration for a function that does not require arguments A prototype declaration for a function that requires two arguments A prototype declaration for a function that utilizes varargs A prototype declaration for a function that utilizes optional arguments A prototype declaration for a function that utilizes named parameters Example of prototype declarations for subroutines or procedures (if these differ from functions) An explanation and example of any special forms of prototyping not covered by the above Languages that do not provide function prototyping facilities should be omitted from this task.
#Lua
Lua
function Func() -- Does not require arguments return 1 end   function Func(a,b) -- Requires arguments return a + b end   function Func(a,b) -- Arguments are optional return a or 4 + b or 2 end   function Func(a,...) -- One argument followed by varargs return a,{...} -- Returns both arguments, varargs as table end
http://rosettacode.org/wiki/Function_prototype
Function prototype
Some languages provide the facility to declare functions and subroutines through the use of function prototyping. Task Demonstrate the methods available for declaring prototypes within the language. The provided solutions should include: An explanation of any placement restrictions for prototype declarations A prototype declaration for a function that does not require arguments A prototype declaration for a function that requires two arguments A prototype declaration for a function that utilizes varargs A prototype declaration for a function that utilizes optional arguments A prototype declaration for a function that utilizes named parameters Example of prototype declarations for subroutines or procedures (if these differ from functions) An explanation and example of any special forms of prototyping not covered by the above Languages that do not provide function prototyping facilities should be omitted from this task.
#Luck
Luck
function noargs(): int = ? ;; function twoargs(x:int, y:int): int = ? ;;   /* underscore means ignore and is not bound to lexical scope */ function twoargs(_:bool, _:bool): int = ? ;;   function anyargs(xs: ...): int = ? ;; function plusargs(x:int, xs: ...): int = ? ;;
http://rosettacode.org/wiki/Function_definition
Function definition
A function is a body of code that returns a value. The value returned may depend on arguments provided to the function. Task Write a definition of a function called "multiply" that takes two arguments and returns their product. (Argument types should be chosen so as not to distract from showing how functions are created and values returned). Related task   Function prototype
#68000_Assembly
68000 Assembly
MOVE.L D0,#$0200 MOVE.L D1,#$0400   JSR doMultiply ;rest of program   JMP $ ;halt   ;;;;; somewhere far away from the code above doMultiply: MULU D0,D1 RTS  
http://rosettacode.org/wiki/French_Republican_calendar
French Republican calendar
Write a program to convert dates between the Gregorian calendar and the French Republican calendar. The year 1 of the Republican calendar began on 22 September 1792. There were twelve months (Vendémiaire, Brumaire, Frimaire, Nivôse, Pluviôse, Ventôse, Germinal, Floréal, Prairial, Messidor, Thermidor, and Fructidor) of 30 days each, followed by five intercalary days or Sansculottides (Fête de la vertu / Virtue Day, Fête du génie / Talent Day, Fête du travail / Labour Day, Fête de l'opinion / Opinion Day, and Fête des récompenses / Honours Day). In leap years (the years 3, 7, and 11) a sixth Sansculottide was added: Fête de la Révolution / Revolution Day. As a minimum, your program should give correct results for dates in the range from 1 Vendémiaire 1 = 22 September 1792 to 10 Nivôse 14 = 31 December 1805 (the last day when the Republican calendar was officially in use). If you choose to accept later dates, be aware that there are several different methods (described on the Wikipedia page) about how to determine leap years after the year 14. You should indicate which method you are using. (Because of these different methods, correct programs may sometimes give different results for dates after 1805.) Test your program by converting the following dates both from Gregorian to Republican and from Republican to Gregorian: • 1 Vendémiaire 1 = 22 September 1792 • 1 Prairial 3 = 20 May 1795 • 27 Messidor 7 = 15 July 1799 (Rosetta Stone discovered) • Fête de la Révolution 11 = 23 September 1803 • 10 Nivôse 14 = 31 December 1805
#Go
Go
package main   import ( "bufio" "fmt" "os" "strconv" "strings" )   var ( gregorianStr = []string{"January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"} gregorian = []int{31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31} republicanStr = []string{"Vendemiaire", "Brumaire", "Frimaire", "Nivose", "Pluviose", "Ventose", "Germinal", "Floreal", "Prairial", "Messidor", "Thermidor", "Fructidor"} sansculottidesStr = []string{"Fete de la vertu", "Fete du genie", "Fete du travail", "Fete de l'opinion", "Fete des recompenses", "Fete de la Revolution"} )   func main() { fmt.Println("*** French Republican ***") fmt.Println("*** calendar converter ***") fmt.Println("Enter a date to convert, in the format 'day month year'") fmt.Println("e.g.: 1 Prairial 3,") fmt.Println(" 20 May 1795.") fmt.Println("For Sansculottides, use 'day year'") fmt.Println("e.g.: Fete de l'opinion 9.") fmt.Println("Or just press 'RETURN' to exit the program.") fmt.Println() for sc := bufio.NewScanner(os.Stdin); ; { fmt.Print("> ") sc.Scan() src := sc.Text() if src == "" { return } day, month, year := split(src) if year < 1792 { day, month, year = dayToGre(repToDay(day, month, year)) fmt.Println(day, gregorianStr[month-1], year) } else { day, month, year := dayToRep(greToDay(day, month, year)) if month == 13 { fmt.Println(sansculottidesStr[day-1], year) } else { fmt.Println(day, republicanStr[month-1], year) } } } }   func split(s string) (d, m, y int) { if strings.HasPrefix(s, "Fete") { m = 13 for i, sc := range sansculottidesStr { if strings.HasPrefix(s, sc) { d = i + 1 y, _ = strconv.Atoi(s[len(sc)+1:]) } } } else { d, _ = strconv.Atoi(s[:strings.Index(s, " ")]) my := s[strings.Index(s, " ")+1:] mStr := my[:strings.Index(my, " ")] y, _ = strconv.Atoi(my[strings.Index(my, " ")+1:]) months := gregorianStr if y < 1792 { months = republicanStr } for i, mn := range months { if mn == mStr { m = i + 1 } } } return }   func greToDay(d, m, y int) int { if m < 3 { y-- m += 12 } return y*36525/100 - y/100 + y/400 + 306*(m+1)/10 + d - 654842 }   func repToDay(d, m, y int) int { if m == 13 { m-- d += 30 } if repLeap(y) { d-- } return 365*y + (y+1)/4 - (y+1)/100 + (y+1)/400 + 30*m + d - 395 }   func dayToGre(day int) (d, m, y int) { y = day * 100 / 36525 d = day - y*36525/100 + 21 y += 1792 d += y/100 - y/400 - 13 m = 8 for d > gregorian[m] { d -= gregorian[m] m++ if m == 12 { m = 0 y++ if greLeap(y) { gregorian[1] = 29 } else { gregorian[1] = 28 } } } m++ return }   func dayToRep(day int) (d, m, y int) { y = (day-1) * 100 / 36525 if repLeap(y) { y-- } d = day - (y+1)*36525/100 + 365 + (y+1)/100 - (y+1)/400 y++ m = 1 sansculottides := 5 if repLeap(y) { sansculottides = 6 } for d > 30 { d -= 30 m += 1 if m == 13 { if d > sansculottides { d -= sansculottides m = 1 y++ sansculottides = 5 if repLeap(y) { sansculottides = 6 } } } } return }   func repLeap(year int) bool { return (year+1)%4 == 0 && ((year+1)%100 != 0 || (year+1)%400 == 0) }   func greLeap(year int) bool { return year%4 == 0 && (year%100 != 0 || year%400 == 0) }
http://rosettacode.org/wiki/Fusc_sequence
Fusc sequence
Definitions The   fusc   integer sequence is defined as:   fusc(0) = 0   fusc(1) = 1   for n>1,   the   nth   term is defined as:   if   n   is even;     fusc(n) = fusc(n/2)   if   n   is   odd;     fusc(n) = fusc((n-1)/2)   +   fusc((n+1)/2) Note that MathWorld's definition starts with unity, not zero.   This task will be using the OEIS' version   (above). An observation   fusc(A) = fusc(B) where   A   is some non-negative integer expressed in binary,   and where   B   is the binary value of   A   reversed. Fusc numbers are also known as:   fusc function   (named by Dijkstra, 1982)   Stern's Diatomic series   (although it starts with unity, not zero)   Stern-Brocot sequence   (although it starts with unity, not zero) Task   show the first   61   fusc numbers (starting at zero) in a horizontal format.   show the fusc number (and its index) whose length is greater than any previous fusc number length.   (the length is the number of decimal digits when the fusc number is expressed in base ten.)   show all numbers with commas   (if appropriate).   show all output here. Related task   RosettaCode Stern-Brocot sequence Also see   the MathWorld entry:   Stern's Diatomic Series.   the OEIS entry:   A2487.
#BASIC256
BASIC256
global f, max max = 36000 dim f(max)   call fusc()   for i = 0 to 60 print f[i]; " "; next i   print : print print " Index Value" d = 0 for i = 0 to max-1 if f[i] >= d then print rjust(string(i),10," "), rjust(string(f[i]),10," ") if d = 0 then d = 1 d *= 10 end if next i end   subroutine fusc() f[0] = 0 : f[1] = 1 for n = 2 to max-1 if (n mod 2) then f[n] = f[(n-1)/2] + f[(n+1)/2] else f[n] = f[n/2] end if next n end subroutine
http://rosettacode.org/wiki/Fusc_sequence
Fusc sequence
Definitions The   fusc   integer sequence is defined as:   fusc(0) = 0   fusc(1) = 1   for n>1,   the   nth   term is defined as:   if   n   is even;     fusc(n) = fusc(n/2)   if   n   is   odd;     fusc(n) = fusc((n-1)/2)   +   fusc((n+1)/2) Note that MathWorld's definition starts with unity, not zero.   This task will be using the OEIS' version   (above). An observation   fusc(A) = fusc(B) where   A   is some non-negative integer expressed in binary,   and where   B   is the binary value of   A   reversed. Fusc numbers are also known as:   fusc function   (named by Dijkstra, 1982)   Stern's Diatomic series   (although it starts with unity, not zero)   Stern-Brocot sequence   (although it starts with unity, not zero) Task   show the first   61   fusc numbers (starting at zero) in a horizontal format.   show the fusc number (and its index) whose length is greater than any previous fusc number length.   (the length is the number of decimal digits when the fusc number is expressed in base ten.)   show all numbers with commas   (if appropriate).   show all output here. Related task   RosettaCode Stern-Brocot sequence Also see   the MathWorld entry:   Stern's Diatomic Series.   the OEIS entry:   A2487.
#BQN
BQN
Fusc ← { { 𝕩∾+´(⍷(⌈∾⌊)2÷˜≠𝕩)⊑¨<𝕩 }⍟(𝕩-2)↕2 }   •Show Fusc 61   •Show >⟨"Index"‿"Number"⟩∾{((1+↕4)⊐˜(⌊1+10⋆⁼1⌈|)¨𝕩){𝕨∾𝕨⊑𝕩}¨<𝕩} Fusc 99999
http://rosettacode.org/wiki/Functional_coverage_tree
Functional coverage tree
Functional coverage is a measure of how much a particular function of a system has been verified as correct. It is used heavily in tracking the completeness of the verification of complex System on Chip (SoC) integrated circuits, where it can also be used to track how well the functional requirements of the system have been verified. This task uses a sub-set of the calculations sometimes used in tracking functional coverage but uses a more familiar(?) scenario. Task Description The head of the clean-up crews for "The Men in a very dark shade of grey when viewed at night" has been tasked with managing the cleansing of two properties after an incident involving aliens. She arranges the task hierarchically with a manager for the crews working on each house who return with a breakdown of how they will report on progress in each house. The overall hierarchy of (sub)tasks is as follows, cleaning house1 bedrooms bathrooms bathroom1 bathroom2 outside lavatory attic kitchen living rooms lounge dining room conservatory playroom basement garage garden house2 upstairs bedrooms suite 1 suite 2 bedroom 3 bedroom 4 bathroom toilet attics groundfloor kitchen living rooms lounge dining room conservatory playroom wet room & toilet garage garden hot tub suite basement cellars wine cellar cinema The head of cleanup knows that her managers will report fractional completion of leaf tasks (tasks with no child tasks of their own), and she knows that she will want to modify the weight of values of completion as she sees fit. Some time into the cleaning, and some coverage reports have come in and she thinks see needs to weight the big house2 60-40 with respect to coverage from house1 She prefers a tabular view of her data where missing weights are assumed to be 1.0 and missing coverage 0.0. NAME_HIERARCHY |WEIGHT |COVERAGE | cleaning | | | house1 |40 | | bedrooms | |0.25 | bathrooms | | | bathroom1 | |0.5 | bathroom2 | | | outside_lavatory | |1 | attic | |0.75 | kitchen | |0.1 | living_rooms | | | lounge | | | dining_room | | | conservatory | | | playroom | |1 | basement | | | garage | | | garden | |0.8 | house2 |60 | | upstairs | | | bedrooms | | | suite_1 | | | suite_2 | | | bedroom_3 | | | bedroom_4 | | | bathroom | | | toilet | | | attics | |0.6 | groundfloor | | | kitchen | | | living_rooms | | | lounge | | | dining_room | | | conservatory | | | playroom | | | wet_room_&_toilet | | | garage | | | garden | |0.9 | hot_tub_suite | |1 | basement | | | cellars | |1 | wine_cellar | |1 | cinema | |0.75 | Calculation The coverage of a node in the tree is calculated as the weighted average of the coverage of its children evaluated bottom-upwards in the tree. The task is to calculate the overall coverage of the cleaning task and display the coverage at all levels of the hierarchy on this page, in a manner that visually shows the hierarchy, weights and coverage of all nodes. Extra Credit After calculating the coverage for all nodes, one can also calculate the additional/delta top level coverage that would occur if any (sub)task were to be fully covered from its current fractional coverage. This is done by multiplying the extra coverage that could be gained 1 − c o v e r a g e {\displaystyle 1-coverage} for any node, by the product of the `powers` of its parent nodes from the top down to the node. The power of a direct child of any parent is given by the power of the parent multiplied by the weight of the child divided by the sum of the weights of all the direct children. The pseudo code would be: method delta_calculation(this, power): sum_of_weights = sum(node.weight for node in children) this.delta = (1 - this.coverage) * power for node in self.children: node.delta_calculation(power * node.weight / sum_of_weights) return this.delta Followed by a call to: top.delta_calculation(power=1) Note: to aid in getting the data into your program you might want to use an alternative, more functional description of the starting data given on the discussion page.
#Racket
Racket
#lang racket/base (require racket/list racket/string racket/match racket/format racket/file)   (struct Coverage (name weight coverage weighted-coverage children) #:transparent #:mutable)   ;; -| read/parse |------------------------------------------------------------------------------------ (define (build-hierarchies parsed-lines) (define inr (match-lambda ['() (values null null)] [`((,head-indent . ,C) ,tail-lines ...) (define child? (match-lambda [(cons i _) #:when (> i head-indent) #t] [_ #f])) (define-values (chlds rels) (splitf-at tail-lines child?)) (define-values (rels-tree rels-rem) (inr rels)) (values (cons (struct-copy Coverage C (children (build-hierarchies chlds))) rels-tree) rels-rem)])) (define-values (hierarchies remaining-lines) (inr parsed-lines)) hierarchies)   (define report-line->indent.c/e-line (match-lambda [(regexp #px"^( *)([^ ]*) *\\| *([^ ]*) *\\| *([^ ]*) *\\|$" (list _ (app string-length indent-length) name (or (and (not "") (app string->number wght)) (app (λ (x) 1) wght)) (or (and (not "") (app string->number cvrg)) (app (λ (x) 0) cvrg)))) (cons indent-length (Coverage name wght cvrg 0 #f))]))   (define (report->indent.c/e-list rprt) (map report-line->indent.c/e-line (drop (string-split rprt "\n") 1)))   ;; -| evaluate |-------------------------------------------------------------------------------------- (define find-wght-cvrg (match-lambda [(and e (Coverage _ w c _ '())) (struct-copy Coverage e (weighted-coverage (* w c)))] [(and e (Coverage _ _ _ _ `(,(app find-wght-cvrg (and cdn+ (Coverage _ c-ws _ c-w/cs _))) ...))) (define chld-wghtd-avg (for/sum ((w (in-list c-ws)) (w/c (in-list c-w/cs))) (* w w/c))) (struct-copy Coverage e (weighted-coverage (/ chld-wghtd-avg (apply + c-ws))) (children cdn+))]))   ;; -| printing |-------------------------------------------------------------------------------------- (define max-description-length (match-lambda [(Coverage (app string-length name-length) _ _ _ (list (app max-description-length children-lengths) ...)) (apply max name-length (map add1 children-lengths))]))   (define (~a/right w x) (~a x #:width w #:align 'right))   (define (~a/decimal n dec-dgts) (~a/right (+ dec-dgts 3) (if (zero? n) "" (real->decimal-string n dec-dgts))))   (define (print-coverage-tree tree) (define mdl (max-description-length tree)) (printf "| ~a |WEIGT| COVER |WGHTD CVRG|~%" (~a "NAME" #:width mdl #:align 'center)) (let inr ((depth 0) (tree tree)) (unless (null? tree) (match tree [(Coverage name w c w/c chlds) (printf "| ~a | ~a | ~a | ~a |~%" (~a (string-append (make-string depth #\space) name) #:width mdl) (~a/right 3 w) (~a/decimal c 2) (~a/decimal w/c 5)) (for ((c chlds)) (inr (add1 depth) c))]))))   ;; --------------------------------------------------------------------------------------------------- (module+ main ;; data/functional-coverage.txt contains a verbatim copy of ;; the table in the task's description (for-each (compose print-coverage-tree find-wght-cvrg) (build-hierarchies (report->indent.c/e-list (file->string "data/functional-coverage.txt")))))
http://rosettacode.org/wiki/Functional_coverage_tree
Functional coverage tree
Functional coverage is a measure of how much a particular function of a system has been verified as correct. It is used heavily in tracking the completeness of the verification of complex System on Chip (SoC) integrated circuits, where it can also be used to track how well the functional requirements of the system have been verified. This task uses a sub-set of the calculations sometimes used in tracking functional coverage but uses a more familiar(?) scenario. Task Description The head of the clean-up crews for "The Men in a very dark shade of grey when viewed at night" has been tasked with managing the cleansing of two properties after an incident involving aliens. She arranges the task hierarchically with a manager for the crews working on each house who return with a breakdown of how they will report on progress in each house. The overall hierarchy of (sub)tasks is as follows, cleaning house1 bedrooms bathrooms bathroom1 bathroom2 outside lavatory attic kitchen living rooms lounge dining room conservatory playroom basement garage garden house2 upstairs bedrooms suite 1 suite 2 bedroom 3 bedroom 4 bathroom toilet attics groundfloor kitchen living rooms lounge dining room conservatory playroom wet room & toilet garage garden hot tub suite basement cellars wine cellar cinema The head of cleanup knows that her managers will report fractional completion of leaf tasks (tasks with no child tasks of their own), and she knows that she will want to modify the weight of values of completion as she sees fit. Some time into the cleaning, and some coverage reports have come in and she thinks see needs to weight the big house2 60-40 with respect to coverage from house1 She prefers a tabular view of her data where missing weights are assumed to be 1.0 and missing coverage 0.0. NAME_HIERARCHY |WEIGHT |COVERAGE | cleaning | | | house1 |40 | | bedrooms | |0.25 | bathrooms | | | bathroom1 | |0.5 | bathroom2 | | | outside_lavatory | |1 | attic | |0.75 | kitchen | |0.1 | living_rooms | | | lounge | | | dining_room | | | conservatory | | | playroom | |1 | basement | | | garage | | | garden | |0.8 | house2 |60 | | upstairs | | | bedrooms | | | suite_1 | | | suite_2 | | | bedroom_3 | | | bedroom_4 | | | bathroom | | | toilet | | | attics | |0.6 | groundfloor | | | kitchen | | | living_rooms | | | lounge | | | dining_room | | | conservatory | | | playroom | | | wet_room_&_toilet | | | garage | | | garden | |0.9 | hot_tub_suite | |1 | basement | | | cellars | |1 | wine_cellar | |1 | cinema | |0.75 | Calculation The coverage of a node in the tree is calculated as the weighted average of the coverage of its children evaluated bottom-upwards in the tree. The task is to calculate the overall coverage of the cleaning task and display the coverage at all levels of the hierarchy on this page, in a manner that visually shows the hierarchy, weights and coverage of all nodes. Extra Credit After calculating the coverage for all nodes, one can also calculate the additional/delta top level coverage that would occur if any (sub)task were to be fully covered from its current fractional coverage. This is done by multiplying the extra coverage that could be gained 1 − c o v e r a g e {\displaystyle 1-coverage} for any node, by the product of the `powers` of its parent nodes from the top down to the node. The power of a direct child of any parent is given by the power of the parent multiplied by the weight of the child divided by the sum of the weights of all the direct children. The pseudo code would be: method delta_calculation(this, power): sum_of_weights = sum(node.weight for node in children) this.delta = (1 - this.coverage) * power for node in self.children: node.delta_calculation(power * node.weight / sum_of_weights) return this.delta Followed by a call to: top.delta_calculation(power=1) Note: to aid in getting the data into your program you might want to use an alternative, more functional description of the starting data given on the discussion page.
#Raku
Raku
sub walktree ($data) { my (@parts, $cnt);   while ($data ~~ m:nth(++$cnt)/$<head>=[(\s*) \N+\n ] # split off one level as 'head' (or terminal 'leaf') $<body>=[[$0 \s+ \N+\n]*]/ ) { # next sub-level is 'body' (defined by extra depth of indentation)   my ($head, $body) = ($<head>, $<body>); $head ~~ /'|' $<weight>=[\S*] \s* '|' $<coverage>=[\S*]/; # save values of weight and coverage (if any) for later   my ($w, $wsum) = (0, 0); $head ~= .[0], $w += .[1], $wsum += .[1] * .[2] for walktree $body;   my $weight = (~$<weight> or 1).fmt('%-8s'); my $coverage = $w == 0 ?? (~$<coverage> or 0).fmt('%-10s') !! ($wsum/$w) .fmt('%-10.2g'); @parts.push: [$head.subst(/'|' \N+/, "|$weight|$coverage|"), $weight, $coverage ]; } return @parts; }   (say .[0] for walktree $_) given   q:to/END/ NAME_HIERARCHY |WEIGHT |COVERAGE | cleaning | | | house1 |40 | | bedrooms | |0.25 | bathrooms | | | bathroom1 | |0.5 | bathroom2 | | | outside_lavatory | |1 | attic | |0.75 | kitchen | |0.1 | living_rooms | | | lounge | | | dining_room | | | conservatory | | | playroom | |1 | basement | | | garage | | | garden | |0.8 | house2 |60 | | upstairs | | | bedrooms | | | suite_1 | | | suite_2 | | | bedroom_3 | | | bedroom_4 | | | bathroom | | | toilet | | | attics | |0.6 | groundfloor | | | kitchen | | | living_rooms | | | lounge | | | dining_room | | | conservatory | | | playroom | | | wet_room_&_toilet | | | garage | | | garden | |0.9 | hot_tub_suite | |1 | basement | | | cellars | |1 | wine_cellar | |1 | cinema | |0.75 | END  
http://rosettacode.org/wiki/Function_frequency
Function frequency
Display - for a program or runtime environment (whatever suits the style of your language) - the top ten most frequently occurring functions (or also identifiers or tokens, if preferred). This is a static analysis: The question is not how often each function is actually executed at runtime, but how often it is used by the programmer. Besides its practical usefulness, the intent of this task is to show how to do self-inspection within the language.
#Haskell
Haskell
import Language.Haskell.Parser (parseModule) import Data.List.Split (splitOn) import Data.List (nub, sortOn, elemIndices)   findApps src = freq $ concat [apps, comps] where ast = show $ parseModule src apps = extract <$> splitApp ast comps = extract <$> concat (splitComp <$> splitInfix ast) splitApp = tail . splitOn "(HsApp (HsVar (UnQual (HsIdent \"" splitInfix = tail . splitOn "(HsInfixApp (HsVar (UnQual (HsIdent \"" splitComp = take 1 . splitOn "(HsQVarOp (UnQual (HsSymbol \"" extract = takeWhile (/= '\"') freq lst = [ (count x lst, x) | x <- nub lst ] count x = length . elemIndices x   main = do src <- readFile "CountFunctions.hs" let res = sortOn (negate . fst) $ findApps src mapM_ (\(n, f) -> putStrLn $ show n ++ "\t" ++ f) res
http://rosettacode.org/wiki/Function_frequency
Function frequency
Display - for a program or runtime environment (whatever suits the style of your language) - the top ten most frequently occurring functions (or also identifiers or tokens, if preferred). This is a static analysis: The question is not how often each function is actually executed at runtime, but how often it is used by the programmer. Besides its practical usefulness, the intent of this task is to show how to do self-inspection within the language.
#J
J
  IGNORE=: ;:'y(0)1',CR   Filter=: (#~`)(`:6)   NB. extract tokens from a large body newline terminated of text roughparse=: ;@(<@;: ::(''"_);._2)   NB. count frequencies and get the top x top=: top=: {. \:~@:((#;{.)/.~)   NB. read all installed script (.ijs) files and concatenate them JSOURCE=: ;fread each 1&e.@('.ijs'&E.)@>Filter {."1 dirtree jpath '~install'   10 top (roughparse JSOURCE)-.IGNORE ┌─────┬──┐ │49591│, │ ├─────┼──┤ │40473│=:│ ├─────┼──┤ │35593│; │ ├─────┼──┤ │34096│=.│ ├─────┼──┤ │24757│+ │ ├─────┼──┤ │18726│" │ ├─────┼──┤ │18564│< │ ├─────┼──┤ │18446│/ │ ├─────┼──┤ │16984│> │ ├─────┼──┤ │14655│@ │ └─────┴──┘  
http://rosettacode.org/wiki/Gamma_function
Gamma function
Task Implement one algorithm (or more) to compute the Gamma ( Γ {\displaystyle \Gamma } ) function (in the real field only). If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in/library function. The Gamma function can be defined as: Γ ( x ) = ∫ 0 ∞ t x − 1 e − t d t {\displaystyle \Gamma (x)=\displaystyle \int _{0}^{\infty }t^{x-1}e^{-t}dt} This suggests a straightforward (but inefficient) way of computing the Γ {\displaystyle \Gamma } through numerical integration. Better suggested methods: Lanczos approximation Stirling's approximation
#C
C
#include <stdio.h> #include <stdlib.h> #include <math.h> #include <gsl/gsl_sf_gamma.h> #ifndef M_PI #define M_PI 3.14159265358979323846 #endif   /* very simple approximation */ double st_gamma(double x) { return sqrt(2.0*M_PI/x)*pow(x/M_E, x); }   #define A 12 double sp_gamma(double z) { const int a = A; static double c_space[A]; static double *c = NULL; int k; double accm;   if ( c == NULL ) { double k1_factrl = 1.0; /* (k - 1)!*(-1)^k with 0!==1*/ c = c_space; c[0] = sqrt(2.0*M_PI); for(k=1; k < a; k++) { c[k] = exp(a-k) * pow(a-k, k-0.5) / k1_factrl; k1_factrl *= -k; } } accm = c[0]; for(k=1; k < a; k++) { accm += c[k] / ( z + k ); } accm *= exp(-(z+a)) * pow(z+a, z+0.5); /* Gamma(z+1) */ return accm/z; }   int main() { double x;     printf("%15s%15s%15s%15s\n", "Stirling", "Spouge", "GSL", "libm"); for(x=1.0; x <= 10.0; x+=1.0) { printf("%15.8lf%15.8lf%15.8lf%15.8lf\n", st_gamma(x/3.0), sp_gamma(x/3.0), gsl_sf_gamma(x/3.0), tgamma(x/3.0)); } return 0; }
http://rosettacode.org/wiki/Galton_box_animation
Galton box animation
Example of a Galton Box at the end of animation. A   Galton device   Sir Francis Galton's device   is also known as a   bean machine,   a   Galton Board,   or a   quincunx. Description of operation In a Galton box, there are a set of pins arranged in a triangular pattern.   A number of balls are dropped so that they fall in line with the top pin, deflecting to the left or the right of the pin.   The ball continues to fall to the left or right of lower pins before arriving at one of the collection points between and to the sides of the bottom row of pins. Eventually the balls are collected into bins at the bottom   (as shown in the image),   the ball column heights in the bins approximate a   bell curve.   Overlaying   Pascal's triangle   onto the pins shows the number of different paths that can be taken to get to each bin. Task Generate an animated simulation of a Galton device. Task requirements   The box should have at least 5 pins on the bottom row.   A solution can use graphics or ASCII animation.   Provide a sample of the output/display such as a screenshot.   There can be one or more balls in flight at the same time.   If multiple balls are in flight, ensure they don't interfere with each other.   A solution should allow users to specify the number of balls, or it should run until full or a preset limit.   Optionally,   display the number of balls.
#Icon_and_Unicon
Icon and Unicon
link graphics   global pegsize, pegsize2, height, width, delay   procedure main(args) # galton box simulation from Unicon book pegsize2 := (pegsize := 10) * 2 # pegs & steps delay := 2 # ms delay setup_galtonwindow(pegsize) n := integer(args[1]) | 100 # balls to drop every 1 to n do galton(pegsize) WDone() end   procedure setup_galtonwindow(n) # Draw n levels of pegs, local xpos, ypos, i, j # Pegboard size is 2n-1 square # Expected max value of histogram is (n, n/2)/2^n # ... approximate with something simpler?   height := n*n/2*pegsize + (width := (2*n+1)*pegsize) Window("size=" || width || "," || height, "fg=grayish-white") WAttrib("fg=dark-grey") every ypos := (i := 1 to n) * pegsize2 do { xpos := width/2 - (i - 1) * pegsize - pegsize/2 - pegsize2 every 1 to i do FillArc(xpos +:= pegsize2, ypos, pegsize, pegsize) } WAttrib("fg=black","drawop=reverse") # set drawing mode for balls end   procedure galton(n) # drop a ball into the galton box local xpos, ypos, oldx, oldy xpos := oldx := width/2 - pegsize/2 ypos := oldy := pegsize every 1 to n do { # For every ball... xpos +:= ((?2 = 1) | -1) * pegsize # +/- pegsize animate(.oldx, .oldy, oldx := xpos, oldy := ypos +:= pegsize2) } animate(xpos, ypos, xpos, ypos + 40) # Now the ball falls ... animate(xpos, ypos+40, xpos, ypos + 200) # ... to the floor draw_ball(xpos) # Record this ball end   procedure animate(xfrom, yfrom, xto, yto) animate_actual(xfrom, yfrom, xto, yfrom, 4) animate_actual(xto, yfrom, xto, yto, 10) end     procedure animate_actual(xfrom, yfrom, xto, yto, steps) # attribs already set local x, y, xstep, ystep, lastx, lasty x -:= xstep := (xto - (x := xfrom))/steps y -:= ystep := (yto - (y := yfrom))/steps every 1 to steps do { FillArc(lastx := x +:= xstep, lasty := y +:= ystep, pegsize, pegsize) WDelay(delay) # wait in ms FillArc(x, y, pegsize, pegsize) } end   procedure draw_ball(x) static ballcounts initial ballcounts := table(0) FillArc(x, height-(ballcounts[x] +:= 1)*pegsize, pegsize, pegsize) end
http://rosettacode.org/wiki/Gapful_numbers
Gapful numbers
Numbers   (positive integers expressed in base ten)   that are (evenly) divisible by the number formed by the first and last digit are known as   gapful numbers. Evenly divisible   means divisible with   no   remainder. All   one─   and two─digit   numbers have this property and are trivially excluded.   Only numbers   ≥ 100   will be considered for this Rosetta Code task. Example 187   is a   gapful   number because it is evenly divisible by the number   17   which is formed by the first and last decimal digits of   187. About   7.46%   of positive integers are   gapful. Task   Generate and show all sets of numbers (below) on one line (horizontally) with a title,   here on this page   Show the first   30   gapful numbers   Show the first   15   gapful numbers   ≥          1,000,000   Show the first   10   gapful numbers   ≥   1,000,000,000 Related tasks   Harshad or Niven series.   palindromic gapful numbers.   largest number divisible by its digits. Also see   The OEIS entry:   A108343 gapful numbers.   numbersaplenty gapful numbers
#Go
Go
package main   import "fmt"   func commatize(n uint64) string { s := fmt.Sprintf("%d", n) le := len(s) for i := le - 3; i >= 1; i -= 3 { s = s[0:i] + "," + s[i:] } return s }   func main() { starts := []uint64{1e2, 1e6, 1e7, 1e9, 7123} counts := []int{30, 15, 15, 10, 25} for i := 0; i < len(starts); i++ { count := 0 j := starts[i] pow := uint64(100) for { if j < pow*10 { break } pow *= 10 } fmt.Printf("First %d gapful numbers starting at %s:\n", counts[i], commatize(starts[i])) for count < counts[i] { fl := (j/pow)*10 + (j % 10) if j%fl == 0 { fmt.Printf("%d ", j) count++ } j++ if j >= 10*pow { pow *= 10 } } fmt.Println("\n") } }
http://rosettacode.org/wiki/Gaussian_elimination
Gaussian elimination
Task Solve   Ax=b   using Gaussian elimination then backwards substitution. A   being an   n by n   matrix. Also,   x and b   are   n by 1   vectors. To improve accuracy, please use partial pivoting and scaling. See also   the Wikipedia entry:   Gaussian elimination
#Haskell
Haskell
  isMatrix xs = null xs || all ((== (length.head $ xs)).length) xs   isSquareMatrix xs = null xs || all ((== (length xs)).length) xs   mult:: Num a => [[a]] -> [[a]] -> [[a]] mult uss vss = map ((\xs -> if null xs then [] else foldl1 (zipWith (+)) xs). zipWith (\vs u -> map (u*) vs) vss) uss   gauss::[[Double]] -> [[Double]] -> [[Double]] gauss xs bs = map (map fromRational) $ solveGauss (toR xs) (toR bs) where toR = map $ map toRational   solveGauss:: (Fractional a, Ord a) => [[a]] -> [[a]] -> [[a]] solveGauss xs bs | null xs || null bs || length xs /= length bs || (not $ isSquareMatrix xs) || (not $ isMatrix bs) = [] | otherwise = uncurry solveTriangle $ triangle xs bs   solveTriangle::(Fractional a,Eq a) => [[a]] -> [[a]] -> [[a]] solveTriangle us _ | not.null.dropWhile ((/= 0).head) $ us = [] solveTriangle ([c]:as) (b:bs) = go as bs [map (/c) b] where val us vs ws = let u = head us in map (/u) $ zipWith (-) vs (head $ mult [tail us] ws) go [] _ zs = zs go _ [] zs = zs go (x:xs) (y:ys) zs = go xs ys $ (val x y zs):zs   triangle::(Num a, Ord a) => [[a]] -> [[a]] -> ([[a]],[[a]]) triangle xs bs = triang ([],[]) (xs,bs) where triang ts (_,[]) = ts triang ts ([],_) = ts triang (os,ps) zs = triang (us:os,cs:ps).unzip $ [(fun tus vs, fun cs es) | (v:vs,es) <- zip uss css,let fun = zipWith (\x y -> v*x - u*y)] where ((us@(u:tus)):uss,cs:css) = bubble zs   bubble::(Num a, Ord a) => ([[a]],[[a]]) -> ([[a]],[[a]]) bubble (xs,bs) = (go xs, go bs) where idmax = snd.maximum.flip zip [0..].map (abs.head) $ xs go ys = let (us,vs) = splitAt idmax ys in vs ++ us   main = do let a = [[1.00, 0.00, 0.00, 0.00, 0.00, 0.00], [1.00, 0.63, 0.39, 0.25, 0.16, 0.10], [1.00, 1.26, 1.58, 1.98, 2.49, 3.13], [1.00, 1.88, 3.55, 6.70, 12.62, 23.80], [1.00, 2.51, 6.32, 15.88, 39.90, 100.28], [1.00, 3.14, 9.87, 31.01, 97.41, 306.02]] let b = [[-0.01], [0.61], [0.91], [0.99], [0.60], [0.02]] mapM_ print $ gauss a b  
http://rosettacode.org/wiki/Gauss-Jordan_matrix_inversion
Gauss-Jordan matrix inversion
Task Invert matrix   A   using Gauss-Jordan method. A   being an   n × n   matrix.
#MATLAB
MATLAB
function GaussInverse(M) original = M; [n,~] = size(M); I = eye(n); for j = 1:n for i = j:n if ~(M(i,j) == 0) for k = 1:n q = M(j,k); M(j,k) = M(i,k); M(i,k) = q; q = I(j,k); I(j,k) = I(i,k); I(i,k) = q; end p = 1/M(j,j); for k = 1:n M(j,k) = p*M(j,k); I(j,k) = p*I(j,k); end for L = 1:n if ~(L == j) p = -M(L,j); for k = 1:n M(L,k) = M(L,k) + p*M(j,k); I(L,k) = I(L,k) + p*I(j,k); end end end end end inverted = I; end fprintf("Matrix:\n") disp(original) fprintf("Inverted matrix:\n") disp(inverted) fprintf("Inverted matrix calculated by built-in function:\n") disp(inv(original)) fprintf("Product of matrix and inverse:\n") disp(original*inverted) end   A = [ 2, -1, 0; -1, 2, -1; 0, -1, 2 ];   GaussInverse(A)
http://rosettacode.org/wiki/General_FizzBuzz
General FizzBuzz
Task Write a generalized version of FizzBuzz that works for any list of factors, along with their words. This is basically a "fizzbuzz" implementation where the user supplies the parameters. The user will enter the max number, then they will enter the factors to be calculated along with the corresponding word to be printed. For simplicity's sake, assume the user will input an integer as the max number and 3 factors, each with a word associated with them. For example, given: >20 #This is the maximum number, supplied by the user >3 Fizz #The user now enters the starting factor (3) and the word they want associated with it (Fizz) >5 Buzz #The user now enters the next factor (5) and the word they want associated with it (Buzz) >7 Baxx #The user now enters the next factor (7) and the word they want associated with it (Baxx) In other words: For this example, print the numbers 1 through 20, replacing every multiple of 3 with "Fizz", every multiple of 5 with "Buzz", and every multiple of 7 with "Baxx". In the case where a number is a multiple of at least two factors, print each of the words associated with those factors in the order of least to greatest factor. For instance, the number 15 is a multiple of both 3 and 5; print "FizzBuzz". If the max number was 105 instead of 20, you would print "FizzBuzzBaxx" because it's a multiple of 3, 5, and 7. Output: 1 2 Fizz 4 Buzz Fizz Baxx 8 Fizz Buzz 11 Fizz 13 Baxx FizzBuzz 16 17 Fizz 19 Buzz
#LiveCode
LiveCode
function generalisedFizzBuzz m, f1, f2, f3 put f1 & cr & f2 & cr & f3 into factors sort factors ascending numeric repeat with i = 1 to m put false into flag if i mod (word 1 of line 1 of factors) = 0 then put word 2 of line 1 of factors after fizzbuzz put true into flag end if if i mod (word 1 of line 2 of factors) = 0 then put word 2 of line 2 of factors after fizzbuzz put true into flag end if if i mod (word 1 of line 3 of factors) = 0 then put word 2 of line 3 of factors after fizzbuzz put true into flag end if if flag is false then put i after fizzbuzz put cr after fizzbuzz end repeat return fizzbuzz end generalisedFizzBuzz
http://rosettacode.org/wiki/General_FizzBuzz
General FizzBuzz
Task Write a generalized version of FizzBuzz that works for any list of factors, along with their words. This is basically a "fizzbuzz" implementation where the user supplies the parameters. The user will enter the max number, then they will enter the factors to be calculated along with the corresponding word to be printed. For simplicity's sake, assume the user will input an integer as the max number and 3 factors, each with a word associated with them. For example, given: >20 #This is the maximum number, supplied by the user >3 Fizz #The user now enters the starting factor (3) and the word they want associated with it (Fizz) >5 Buzz #The user now enters the next factor (5) and the word they want associated with it (Buzz) >7 Baxx #The user now enters the next factor (7) and the word they want associated with it (Baxx) In other words: For this example, print the numbers 1 through 20, replacing every multiple of 3 with "Fizz", every multiple of 5 with "Buzz", and every multiple of 7 with "Baxx". In the case where a number is a multiple of at least two factors, print each of the words associated with those factors in the order of least to greatest factor. For instance, the number 15 is a multiple of both 3 and 5; print "FizzBuzz". If the max number was 105 instead of 20, you would print "FizzBuzzBaxx" because it's a multiple of 3, 5, and 7. Output: 1 2 Fizz 4 Buzz Fizz Baxx 8 Fizz Buzz 11 Fizz 13 Baxx FizzBuzz 16 17 Fizz 19 Buzz
#Lua
Lua
function genFizz (param) local response print("\n") for n = 1, param.limit do response = "" for i = 1, 3 do if n % param.factor[i] == 0 then response = response .. param.word[i] end end if response == "" then print(n) else print(response) end end end   local param = {factor = {}, word = {}} param.limit = io.read() for i = 1, 3 do param.factor[i], param.word[i] = io.read("*number", "*line") end genFizz(param)
http://rosettacode.org/wiki/Generate_lower_case_ASCII_alphabet
Generate lower case ASCII alphabet
Task Generate an array, list, lazy sequence, or even an indexable string of all the lower case ASCII characters, from a to z. If the standard library contains such a sequence, show how to access it, but don't fail to show how to generate a similar sequence. For this basic task use a reliable style of coding, a style fit for a very large program, and use strong typing if available. It's bug prone to enumerate all the lowercase characters manually in the code. During code review it's not immediate obvious to spot the bug in a Tcl line like this contained in a page of code: set alpha {a b c d e f g h i j k m n o p q r s t u v w x y z} Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Elena
Elena
import extensions; import system'collections;   singleton Alphabet : Enumerable { Enumerator enumerator() = new Enumerator { char current;   get() = current;   bool next() { if (nil==current) { current := $97 } else if (current != $122) { current := (current.toInt() + 1).toChar() } else { ^ false };   ^ true }   reset() { current := nil }   enumerable() = self; }; }   public program() { console.printLine(Alphabet) }
http://rosettacode.org/wiki/Generate_lower_case_ASCII_alphabet
Generate lower case ASCII alphabet
Task Generate an array, list, lazy sequence, or even an indexable string of all the lower case ASCII characters, from a to z. If the standard library contains such a sequence, show how to access it, but don't fail to show how to generate a similar sequence. For this basic task use a reliable style of coding, a style fit for a very large program, and use strong typing if available. It's bug prone to enumerate all the lowercase characters manually in the code. During code review it's not immediate obvious to spot the bug in a Tcl line like this contained in a page of code: set alpha {a b c d e f g h i j k m n o p q r s t u v w x y z} Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Elixir
Elixir
iex(1)> Enum.to_list(?a .. ?z) 'abcdefghijklmnopqrstuvwxyz' iex(2)> Enum.to_list(?a .. ?z) |> List.to_string "abcdefghijklmnopqrstuvwxyz"
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#ooRexx
ooRexx
/* Rexx */ say 'Hello world!'  
http://rosettacode.org/wiki/Generator/Exponential
Generator/Exponential
A generator is an executable entity (like a function or procedure) that contains code that yields a sequence of values, one at a time, so that each time you call the generator, the next value in the sequence is provided. Generators are often built on top of coroutines or objects so that the internal state of the object is handled “naturally”. Generators are often used in situations where a sequence is potentially infinite, and where it is possible to construct the next value of the sequence with only minimal state. Task Create a function that returns a generation of the m'th powers of the positive integers starting from zero, in order, and without obvious or simple upper limit. (Any upper limit to the generator should not be stated in the source but should be down to factors such as the languages natural integer size limit or computational time/size). Use it to create a generator of:   Squares.   Cubes. Create a new generator that filters all cubes from the generator of squares. Drop the first 20 values from this last generator of filtered results, and then show the next 10 values. Note that this task requires the use of generators in the calculation of the result. Also see Generator
#M2000_Interpreter
M2000 Interpreter
  Module Generator { PowGen = Lambda (e)-> { =lambda i=0, e -> { i++ =i**e } }   Squares=lambda PowGen=PowGen(2) ->{ =PowGen() }   Cubes=Lambda PowGen=PowGen(3) -> { =PowGen() }   Filter=Lambda z=Squares(), Squares, m, Cubes->{ while m<Z {m=cubes()} if z=m then z=Squares() =z z=Squares() }   For i=1 to 20 : dropit=Filter() :Next i   Document doc$="Non-cubic squares (21st to 30th)" Print doc$ \\ a new line to doc$ doc$={ } For i=1 to 10 { f=Filter() Print Format$("I: {0::-2}, F: {1}",i+20, f) doc$=Format$("I: {0::-2}, F: {1}",i+20, f)+{ } } Clipboard doc$ } Generator  
http://rosettacode.org/wiki/Generate_Chess960_starting_position
Generate Chess960 starting position
Chess960 is a variant of chess created by world champion Bobby Fischer. Unlike other variants of the game, Chess960 does not require a different material, but instead relies on a random initial position, with a few constraints: as in the standard chess game, all eight white pawns must be placed on the second rank. White pieces must stand on the first rank as in the standard game, in random column order but with the two following constraints: the bishops must be placed on opposite color squares (i.e. they must be an odd number of spaces apart or there must be an even number of spaces between them) the King must be between two rooks (with any number of other pieces between them all) Black pawns and pieces must be placed respectively on the seventh and eighth ranks, mirroring the white pawns and pieces, just as in the standard game. (That is, their positions are not independently randomized.) With those constraints there are 960 possible starting positions, thus the name of the variant. Task The purpose of this task is to write a program that can randomly generate any one of the 960 Chess960 initial positions. You will show the result as the first rank displayed with Chess symbols in Unicode: ♔♕♖♗♘ or with the letters King Queen Rook Bishop kNight.
#Racket
Racket
#lang racket (define white (match-lambda ['P #\♙] ['R #\♖] ['B #\♗] ['N #\♘] ['Q #\♕] ['K #\♔])) (define black (match-lambda ['P #\♟] ['R #\♜] ['B #\♝] ['N #\♞] ['Q #\♛] ['K #\♚]))   (define (piece->unicode piece colour) (match colour ('w white) ('b black)) piece)   (define (find/set!-random-slot vec val k (f values)) (define r (f (random k))) (cond [(vector-ref vec r) (find/set!-random-slot vec val k f)] [else (vector-set! vec r val) r]))   (define (chess960-start-position) (define v (make-vector 8 #f))  ;; Kings and Rooks (let ((k (find/set!-random-slot v (white 'K) 6 add1))) (find/set!-random-slot v (white 'R) k) (find/set!-random-slot v (white 'R) (- 7 k) (curry + k 1)))  ;; Bishops -- so far only three squares allocated, so there is at least one of each colour left (find/set!-random-slot v (white 'B) 4 (curry * 2)) (find/set!-random-slot v (white 'B) 4 (compose add1 (curry * 2)))  ;; Everyone else (find/set!-random-slot v (white 'Q) 8) (find/set!-random-slot v (white 'N) 8) (find/set!-random-slot v (white 'N) 8) (list->string (vector->list v)))   (chess960-start-position)
http://rosettacode.org/wiki/Generate_Chess960_starting_position
Generate Chess960 starting position
Chess960 is a variant of chess created by world champion Bobby Fischer. Unlike other variants of the game, Chess960 does not require a different material, but instead relies on a random initial position, with a few constraints: as in the standard chess game, all eight white pawns must be placed on the second rank. White pieces must stand on the first rank as in the standard game, in random column order but with the two following constraints: the bishops must be placed on opposite color squares (i.e. they must be an odd number of spaces apart or there must be an even number of spaces between them) the King must be between two rooks (with any number of other pieces between them all) Black pawns and pieces must be placed respectively on the seventh and eighth ranks, mirroring the white pawns and pieces, just as in the standard game. (That is, their positions are not independently randomized.) With those constraints there are 960 possible starting positions, thus the name of the variant. Task The purpose of this task is to write a program that can randomly generate any one of the 960 Chess960 initial positions. You will show the result as the first rank displayed with Chess symbols in Unicode: ♔♕♖♗♘ or with the letters King Queen Rook Bishop kNight.
#Raku
Raku
repeat until m/ '♗' [..]* '♗' / { $_ = < ♖ ♖ ♖ ♕ ♗ ♗ ♘ ♘ >.pick(*).join } s:2nd['♖'] = '♔'; say .comb;
http://rosettacode.org/wiki/Function_composition
Function composition
Task Create a function, compose,   whose two arguments   f   and   g,   are both functions with one argument. The result of compose is to be a function of one argument, (lets call the argument   x),   which works like applying function   f   to the result of applying function   g   to   x. Example compose(f, g) (x) = f(g(x)) Reference: Function composition Hint: In some languages, implementing compose correctly requires creating a closure.
#Applesoft_BASIC
Applesoft BASIC
10 F$ = "SIN" 20 DEF FN A(P) = ATN(P/SQR(-P*P+1)) 30 G$ = "FN A" 40 GOSUB 100"COMPOSE 50 SA$ = E$   60 X = .5 : E$ = SA$ 70 GOSUB 200"EXEC 80 PRINT R 90 END   100 E$ = F$ + "(" + G$ + "(X))" : RETURN : REMCOMPOSE F$ G$   200 D$ = CHR$(4) : FI$ = "TEMPORARY.EX" : M$ = CHR$(13) 210 PRINT D$"OPEN"FI$M$D$"CLOSE"FI$M$D$"DELETE"FI$ 220 PRINT D$"OPEN"FI$M$D$"WRITE"FI$ 230 PRINT "CALL-998:CALL-958:R="E$":CONT" 240 PRINT D$"CLOSE"FI$M$D$"EXEC"FI$:CALL-998:END:RETURN
http://rosettacode.org/wiki/Function_composition
Function composition
Task Create a function, compose,   whose two arguments   f   and   g,   are both functions with one argument. The result of compose is to be a function of one argument, (lets call the argument   x),   which works like applying function   f   to the result of applying function   g   to   x. Example compose(f, g) (x) = f(g(x)) Reference: Function composition Hint: In some languages, implementing compose correctly requires creating a closure.
#Argile
Argile
use std, math   let my_asin = new Function (.:<any,real x>:. -> real {asin x}) let my__sin = new Function (.:<any,real x>:. -> real { sin x}) let sinasin = my__sin o my_asin print sin asin 0.5 print *my__sin 0.0 print *sinasin 0.5 ~my_asin ~my__sin ~sinasin   =: <Function f> o <Function g> := -> Function {compose f g}   .:compose <Function f, Function g>:. -> Function use array let d = (new array of 2 Function) (d[0]) = f ; (d[1]) = g let c = new Function (.:<array of Function fg, real x>:. -> real { *fg[0]( *fg[1](x) ) }) (d) c.del = .:<any>:.{free any} c   class Function function(any)(real)->(real) func any data function(any) del   =: * <Function f> <real x> := -> real Cgen "(*("(f.func)"))("(f.data)", "(x)")"   .: del Function <Function f> :. unless f.del is nil call f.del with f.data free f =: ~ <Function f> := {del Function f}   .: new Function <function(any)(real)-\>real func> (<any data>):. -> Function let f = new Function f.func = func f.data = data f
http://rosettacode.org/wiki/Fractran
Fractran
FRACTRAN is a Turing-complete esoteric programming language invented by the mathematician John Horton Conway. A FRACTRAN program is an ordered list of positive fractions P = ( f 1 , f 2 , … , f m ) {\displaystyle P=(f_{1},f_{2},\ldots ,f_{m})} , together with an initial positive integer input n {\displaystyle n} . The program is run by updating the integer n {\displaystyle n} as follows: for the first fraction, f i {\displaystyle f_{i}} , in the list for which n f i {\displaystyle nf_{i}} is an integer, replace n {\displaystyle n} with n f i {\displaystyle nf_{i}}  ; repeat this rule until no fraction in the list produces an integer when multiplied by n {\displaystyle n} , then halt. Conway gave a program for primes in FRACTRAN: 17 / 91 {\displaystyle 17/91} , 78 / 85 {\displaystyle 78/85} , 19 / 51 {\displaystyle 19/51} , 23 / 38 {\displaystyle 23/38} , 29 / 33 {\displaystyle 29/33} , 77 / 29 {\displaystyle 77/29} , 95 / 23 {\displaystyle 95/23} , 77 / 19 {\displaystyle 77/19} , 1 / 17 {\displaystyle 1/17} , 11 / 13 {\displaystyle 11/13} , 13 / 11 {\displaystyle 13/11} , 15 / 14 {\displaystyle 15/14} , 15 / 2 {\displaystyle 15/2} , 55 / 1 {\displaystyle 55/1} Starting with n = 2 {\displaystyle n=2} , this FRACTRAN program will change n {\displaystyle n} to 15 = 2 × ( 15 / 2 ) {\displaystyle 15=2\times (15/2)} , then 825 = 15 × ( 55 / 1 ) {\displaystyle 825=15\times (55/1)} , generating the following sequence of integers: 2 {\displaystyle 2} , 15 {\displaystyle 15} , 825 {\displaystyle 825} , 725 {\displaystyle 725} , 1925 {\displaystyle 1925} , 2275 {\displaystyle 2275} , 425 {\displaystyle 425} , 390 {\displaystyle 390} , 330 {\displaystyle 330} , 290 {\displaystyle 290} , 770 {\displaystyle 770} , … {\displaystyle \ldots } After 2, this sequence contains the following powers of 2: 2 2 = 4 {\displaystyle 2^{2}=4} , 2 3 = 8 {\displaystyle 2^{3}=8} , 2 5 = 32 {\displaystyle 2^{5}=32} , 2 7 = 128 {\displaystyle 2^{7}=128} , 2 11 = 2048 {\displaystyle 2^{11}=2048} , 2 13 = 8192 {\displaystyle 2^{13}=8192} , 2 17 = 131072 {\displaystyle 2^{17}=131072} , 2 19 = 524288 {\displaystyle 2^{19}=524288} , … {\displaystyle \ldots } which are the prime powers of 2. Task Write a program that reads a list of fractions in a natural format from the keyboard or from a string, to parse it into a sequence of fractions (i.e. two integers), and runs the FRACTRAN starting from a provided integer, writing the result at each step. It is also required that the number of steps is limited (by a parameter easy to find). Extra credit Use this program to derive the first 20 or so prime numbers. See also For more on how to program FRACTRAN as a universal programming language, see: J. H. Conway (1987). Fractran: A Simple Universal Programming Language for Arithmetic. In: Open Problems in Communication and Computation, pages 4–26. Springer. J. H. Conway (2010). "FRACTRAN: A simple universal programming language for arithmetic". In Jeffrey C. Lagarias. The Ultimate Challenge: the 3x+1 problem. American Mathematical Society. pp. 249–264. ISBN 978-0-8218-4940-8. Zbl 1216.68068. Number Pathology: Fractran by Mark C. Chu-Carroll; October 27, 2006.
#360_Assembly
360 Assembly
* FRACTRAN 17/02/2019 FRACTRAN CSECT USING FRACTRAN,R13 base register B 72(R15) skip savearea DC 17F'0' savearea SAVE (14,12) save previous context ST R13,4(R15) link backward ST R15,8(R13) link forward LR R13,R15 set addressability LA R6,1 i=1 DO WHILE=(C,R6,LE,TERMS) do i=1 to terms LA R7,1 j=1 DO WHILE=(C,R7,LE,=A(NF)) do j=1 to nfracs LR R1,R7 j SLA R1,3 ~ L R2,FRACS-4(R1) d(j) L R4,NN nn SRDA R4,32 ~ DR R4,R2 nn/d(j) IF LTR,R4,Z,R4 THEN if mod(nn,d(j))=0 then XDECO R6,XDEC edit i MVC PG(3),XDEC+9 output i L R1,NN nn XDECO R1,PG+5 edit & output nn XPRNT PG,L'PG print buffer LR R1,R7 j SLA R1,3 ~ L R3,FRACS-8(R1) n(j) MR R4,R3 *n(j) ST R5,NN nn=nn/d(j)*n(j) B LEAVEJ leave j ENDIF , end if LA R7,1(R7) j++ ENDDO , end do j LEAVEJ LA R6,1(R6) i++ ENDDO , end do i L R13,4(0,R13) restore previous savearea pointer RETURN (14,12),RC=0 restore registers from calling sav NF EQU (TERMS-FRACS)/8 number of fracs NN DC F'2' nn FRACS DC F'17',F'91',F'78',F'85',F'19',F'51',F'23',F'38',F'29',F'33' DC F'77',F'29',F'95',F'23',F'77',F'19',F'1',F'17',F'11',F'13' DC F'13',F'11',F'15',F'14',F'15',F'2',F'55',F'1' TERMS DC F'100' terms PG DC CL80'*** :' buffer XDEC DS CL12 temp REGEQU END FRACTRAN
http://rosettacode.org/wiki/FTP
FTP
Task Connect to a server, change directory, list its contents and download a file as binary using the FTP protocol. Use passive mode if available.
#Haskell
Haskell
module Main (main) where   import Control.Exception (bracket) import Control.Monad (void) import Data.Foldable (for_) import Network.FTP.Client ( cwd , easyConnectFTP , getbinary , loginAnon , nlst , quit , setPassive )   main :: IO () main = bracket ((flip setPassive) True <$> easyConnectFTP "ftp.kernel.org") quit $ \h -> do -- Log in anonymously void $ loginAnon h   -- Change directory void $ cwd h "/pub/linux/kernel/Historic"   -- List current directory fileNames <- nlst h Nothing for_ fileNames $ \fileName -> putStrLn fileName   -- Download in binary mode (fileData, _) <- getbinary h "linux-0.01.tar.gz.sign" print fileData
http://rosettacode.org/wiki/FTP
FTP
Task Connect to a server, change directory, list its contents and download a file as binary using the FTP protocol. Use passive mode if available.
#J
J
require 'web/gethttp' gethttp 'ftp://anonymous:[email protected]/pub/issoutreach/Living%20in%20Space%20Stories%20(MP3%20Files)/' -rw-rw-r-- 1 109 space-station 2327118 May 9 2005 09sept_spacepropulsion.mp3 -rw-rw-r-- 1 109 space-station 1260304 May 9 2005 Can People go to Mars.mp3 -rw-rw-r-- 1 109 space-station 1350270 May 9 2005 Distill some water.mp3 -rw-rw-r-- 1 109 space-station 1290888 May 9 2005 Good Vibrations.mp3 -rw-rw-r-- 1 109 space-station 1431834 May 9 2005 Gravity Hurts_So good.mp3 -rw-rw-r-- 1 109 space-station 1072644 May 9 2005 Gravity in the Brain.mp3 -rw-rw-r-- 1 109 space-station 1230594 May 9 2005 Power to the ISS.mp3 -rw-rw-r-- 1 109 space-station 1309062 May 9 2005 Space Bones.mp3 -rw-rw-r-- 1 109 space-station 2292715 May 9 2005 Space Power.mp3 -rw-rw-r-- 1 109 space-station 772075 May 9 2005 We have a solution.mp3 -rw-rw-r-- 1 109 space-station 1134654 May 9 2005 When Space Makes you Dizzy.mp3 #file=: gethttp rplc&(' ';'%20') 'ftp://anonymous:[email protected]/pub/issoutreach/Living in Space Stories (MP3 Files)/We have a solution.mp3' 772075
http://rosettacode.org/wiki/Function_prototype
Function prototype
Some languages provide the facility to declare functions and subroutines through the use of function prototyping. Task Demonstrate the methods available for declaring prototypes within the language. The provided solutions should include: An explanation of any placement restrictions for prototype declarations A prototype declaration for a function that does not require arguments A prototype declaration for a function that requires two arguments A prototype declaration for a function that utilizes varargs A prototype declaration for a function that utilizes optional arguments A prototype declaration for a function that utilizes named parameters Example of prototype declarations for subroutines or procedures (if these differ from functions) An explanation and example of any special forms of prototyping not covered by the above Languages that do not provide function prototyping facilities should be omitted from this task.
#M2000_Interpreter
M2000 Interpreter
  Module Check { Module MyBeta (a) { Print "MyBeta", a/2 } Module TestMe { Module Beta (x) { Print "TestMeBeta", x } Beta 100 } TestMe ; Beta as MyBeta } Check  
http://rosettacode.org/wiki/Function_prototype
Function prototype
Some languages provide the facility to declare functions and subroutines through the use of function prototyping. Task Demonstrate the methods available for declaring prototypes within the language. The provided solutions should include: An explanation of any placement restrictions for prototype declarations A prototype declaration for a function that does not require arguments A prototype declaration for a function that requires two arguments A prototype declaration for a function that utilizes varargs A prototype declaration for a function that utilizes optional arguments A prototype declaration for a function that utilizes named parameters Example of prototype declarations for subroutines or procedures (if these differ from functions) An explanation and example of any special forms of prototyping not covered by the above Languages that do not provide function prototyping facilities should be omitted from this task.
#Nim
Nim
# Procedure declarations. All are named proc noargs(): int proc twoargs(a, b: int): int proc anyargs(x: varargs[int]): int proc optargs(a, b: int = 10): int   # Usage discard noargs() discard twoargs(1,2) discard anyargs(1,2,3,4,5,6,7,8) discard optargs(5)   # Procedure definitions proc noargs(): int = echo "noargs" proc twoargs(a, b: int): int = echo "twoargs" proc anyargs(x: varargs[int]): int = echo "anyargs" proc optargs(a: int, b = 10): int = echo "optargs"
http://rosettacode.org/wiki/Function_prototype
Function prototype
Some languages provide the facility to declare functions and subroutines through the use of function prototyping. Task Demonstrate the methods available for declaring prototypes within the language. The provided solutions should include: An explanation of any placement restrictions for prototype declarations A prototype declaration for a function that does not require arguments A prototype declaration for a function that requires two arguments A prototype declaration for a function that utilizes varargs A prototype declaration for a function that utilizes optional arguments A prototype declaration for a function that utilizes named parameters Example of prototype declarations for subroutines or procedures (if these differ from functions) An explanation and example of any special forms of prototyping not covered by the above Languages that do not provide function prototyping facilities should be omitted from this task.
#OCaml
OCaml
(* Usually prototype declarations are put in an interface file, a file with .mli filename extension *)   (* A prototype declaration for a function that does not require arguments *) val no_arg : unit -> unit   (* A prototype declaration for a function that requires two arguments *) val two_args : int -> int -> unit   (* A prototype declaration for a function that utilizes optional arguments *) val opt_arg : ?param:int -> unit -> unit (* in this case we add a unit parameter in order to omit the argument, because ocaml supports partial application *)   (* A prototype declaration for a function that utilizes named parameters *) val named_arg : param1:int -> param2:int -> unit   (* An explanation and example of any special forms of prototyping not covered by the above *)   (* A prototype declaration for a function that requires a function argument *) val fun_arg : (int -> int) -> unit   (* A prototype declaration for a function with polymorphic argument *) val poly_arg : 'a -> unit
http://rosettacode.org/wiki/Function_definition
Function definition
A function is a body of code that returns a value. The value returned may depend on arguments provided to the function. Task Write a definition of a function called "multiply" that takes two arguments and returns their product. (Argument types should be chosen so as not to distract from showing how functions are created and values returned). Related task   Function prototype
#8051_Assembly
8051 Assembly
ORG RESET mov a, #100 mov b, #10 call multiply ; at this point, the result of 100*10 = 1000 = 03e8h is stored in registers a and b ; a = e8 ; b = 03 jmp $   multiply: mul ab ret
http://rosettacode.org/wiki/French_Republican_calendar
French Republican calendar
Write a program to convert dates between the Gregorian calendar and the French Republican calendar. The year 1 of the Republican calendar began on 22 September 1792. There were twelve months (Vendémiaire, Brumaire, Frimaire, Nivôse, Pluviôse, Ventôse, Germinal, Floréal, Prairial, Messidor, Thermidor, and Fructidor) of 30 days each, followed by five intercalary days or Sansculottides (Fête de la vertu / Virtue Day, Fête du génie / Talent Day, Fête du travail / Labour Day, Fête de l'opinion / Opinion Day, and Fête des récompenses / Honours Day). In leap years (the years 3, 7, and 11) a sixth Sansculottide was added: Fête de la Révolution / Revolution Day. As a minimum, your program should give correct results for dates in the range from 1 Vendémiaire 1 = 22 September 1792 to 10 Nivôse 14 = 31 December 1805 (the last day when the Republican calendar was officially in use). If you choose to accept later dates, be aware that there are several different methods (described on the Wikipedia page) about how to determine leap years after the year 14. You should indicate which method you are using. (Because of these different methods, correct programs may sometimes give different results for dates after 1805.) Test your program by converting the following dates both from Gregorian to Republican and from Republican to Gregorian: • 1 Vendémiaire 1 = 22 September 1792 • 1 Prairial 3 = 20 May 1795 • 27 Messidor 7 = 15 July 1799 (Rosetta Stone discovered) • Fête de la Révolution 11 = 23 September 1803 • 10 Nivôse 14 = 31 December 1805
#Julia
Julia
using Dates   const GC_FORMAT = DateFormat("d U y")   const RC_FIRST_DAY = Date(1792, 9, 22)   const MAX_RC_DATE = Date(1805, 12, 31)   const RC_MONTHS = [ "Vendémiaire", "Brumaire", "Frimaire", "Nivôse", "Pluviôse", "Ventôse", "Germinal", "Floréal", "Prairial", "Messidor", "Thermidor", "Fructidor" ]   const RC_DAYS_IN_MONTH = 30   const RC_SANSCULOTTIDES = [ "Fête de la vertu", "Fête du génie", "Fête du travail", "Fête de l'opinion", "Fête des récompenses", "Fête de la Révolution" ]   additionaldaysforyear(yr) = yr > 11 ? 3 : yr > 7 ? 2 : yr > 3 ? 1 : 0 additionaldaysformonth(mo) = 30 * (mo - 1) daysforFete(s) = findfirst(x -> x == s, RC_SANSCULOTTIDES) + 359   function togregorian(rc::String) yearstring, firstpart = reverse.(split(reverse(strip(rc)), r"\s+", limit=2)) rcyear = parse(Int, yearstring) pastyeardays = (rcyear - 1) * 365 + additionaldaysforyear(rcyear) if isnumeric(firstpart[1]) daystring, monthstring = split(firstpart, r"\s+", limit=2) nmonth = findfirst(x -> x == monthstring, RC_MONTHS) pastmonthdays = 30 * (nmonth - 1) furtherdays = parse(Int, daystring) + pastmonthdays + pastyeardays - 1 else furtherdays = daysforFete(firstpart) + pastyeardays end gregorian = RC_FIRST_DAY + Day(furtherdays) if furtherdays < 0 || gregorian > MAX_RC_DATE throw(DomainError("French Republican Calendar date out of range")) end return Day(gregorian).value, monthname(Month(gregorian).value), Year(gregorian).value end   function torepublican(gc::String) date = Date(DateTime(gc, GC_FORMAT)) if date < RC_FIRST_DAY || date > MAX_RC_DATE throw(DomainError("French Republican Calendar date out of range")) end rcyear, rcdays = divrem(((date - RC_FIRST_DAY).value + 366), 365) rcdays -= additionaldaysforyear(rcyear) if rcdays < 1 rcyear -= 1 rcdays += 366 end if rcdays < 361 nmonth, rcday = divrem(rcdays, 30) return rcday, RC_MONTHS[nmonth + 1], rcyear else return RC_SANSCULOTTIDES[rcdays - 360], rcyear end end   const republican = [ "1 Vendémiaire 1", "1 Prairial 3", "27 Messidor 7", "Fête de la Révolution 11", "10 Nivôse 14" ]   const gregorian = [ "22 September 1792", "20 May 1795", "15 July 1799", "23 September 1803", "31 December 1805" ]   function testrepublicancalendar() println("French Republican to Gregorian") for s in republican println(lpad(s, 24), " => ", togregorian(s)) end println("Gregorian to French Republican") for s in gregorian println(lpad(s, 24), " => ", torepublican(s)) end end   testrepublicancalendar()  
http://rosettacode.org/wiki/French_Republican_calendar
French Republican calendar
Write a program to convert dates between the Gregorian calendar and the French Republican calendar. The year 1 of the Republican calendar began on 22 September 1792. There were twelve months (Vendémiaire, Brumaire, Frimaire, Nivôse, Pluviôse, Ventôse, Germinal, Floréal, Prairial, Messidor, Thermidor, and Fructidor) of 30 days each, followed by five intercalary days or Sansculottides (Fête de la vertu / Virtue Day, Fête du génie / Talent Day, Fête du travail / Labour Day, Fête de l'opinion / Opinion Day, and Fête des récompenses / Honours Day). In leap years (the years 3, 7, and 11) a sixth Sansculottide was added: Fête de la Révolution / Revolution Day. As a minimum, your program should give correct results for dates in the range from 1 Vendémiaire 1 = 22 September 1792 to 10 Nivôse 14 = 31 December 1805 (the last day when the Republican calendar was officially in use). If you choose to accept later dates, be aware that there are several different methods (described on the Wikipedia page) about how to determine leap years after the year 14. You should indicate which method you are using. (Because of these different methods, correct programs may sometimes give different results for dates after 1805.) Test your program by converting the following dates both from Gregorian to Republican and from Republican to Gregorian: • 1 Vendémiaire 1 = 22 September 1792 • 1 Prairial 3 = 20 May 1795 • 27 Messidor 7 = 15 July 1799 (Rosetta Stone discovered) • Fête de la Révolution 11 = 23 September 1803 • 10 Nivôse 14 = 31 December 1805
#Kotlin
Kotlin
// version 1.1.4-3   import java.time.format.DateTimeFormatter import java.time.LocalDate import java.time.temporal.ChronoUnit.DAYS   /* year = 1.. month = 1..13 day = 1..30 */ class FrenchRCDate(val year: Int, val month: Int, val day: Int) {   init { require (year > 0 && month in 1..13) if (month < 13) require (day in 1..30) else { val leap = isLeapYear(year) require (day in (if (leap) 1..6 else 1..5)) } }   override fun toString() = if (month < 13) "$day ${months[month - 1]} $year" else "${intercal[day - 1]} $year"   fun toLocalDate(): LocalDate { var sumDays = 0L for (i in 1 until year) sumDays += if (isLeapYear(i)) 366 else 365 val dayInYear = (month - 1) * 30 + day - 1 return introductionDate.plusDays(sumDays + dayInYear) }   companion object { /* uses the 'continuous method' for years after 1805 */ fun isLeapYear(y: Int): Boolean { val yy = y + 1 return (yy % 4 == 0) && (yy % 100 != 0 || yy % 400 == 0) }   fun parse(frcDate: String): FrenchRCDate { val splits = frcDate.trim().split(' ') if (splits.size == 3) { val month = months.indexOf(splits[1]) + 1 require(month in 1..13) val year = splits[2].toIntOrNull() ?: 0 require(year > 0) val monthLength = if (month < 13) 30 else if (isLeapYear(year)) 6 else 5 val day = splits[0].toIntOrNull() ?: 0 require(day in 1..monthLength) return FrenchRCDate(year, month, day) } else if (splits.size in 4..5) { val yearStr = splits[splits.lastIndex] val year = yearStr.toIntOrNull() ?: 0 require(year > 0) val scDay = frcDate.trim().dropLast(yearStr.length + 1) val day = intercal.indexOf(scDay) + 1 val maxDay = if (isLeapYear(year)) 6 else 5 require (day in 1..maxDay) return FrenchRCDate(year, 13, day) } else throw IllegalArgumentException("Invalid French Republican date") }   /* for convenience we treat 'Sansculottide' as an extra month with 5 or 6 days */ val months = arrayOf( "Vendémiaire", "Brumaire", "Frimaire", "Nivôse", "Pluviôse", "Ventôse", "Germinal", "Floréal", "Prairial", "Messidor", "Thermidor", "Fructidor", "Sansculottide" )   val intercal = arrayOf( "Fête de la vertu", "Fête du génie", "Fête du travail", "Fête de l'opinion", "Fête des récompenses", "Fête de la Révolution" )   val introductionDate = LocalDate.of(1792, 9, 22) } }   fun LocalDate.toFrenchRCDate(): FrenchRCDate { val daysDiff = DAYS.between(FrenchRCDate.introductionDate, this).toInt() + 1 if (daysDiff <= 0) throw IllegalArgumentException("Date can't be before 22 September 1792") var year = 1 var startDay = 1 while (true) { val endDay = startDay + if (FrenchRCDate.isLeapYear(year)) 365 else 364 if (daysDiff in startDay..endDay) break year++ startDay = endDay + 1 } val remDays = daysDiff - startDay val month = remDays / 30 val day = remDays - month * 30 return FrenchRCDate(year, month + 1, day + 1) }   fun main(args: Array<String>) { val formatter = DateTimeFormatter.ofPattern("d MMMM yyyy") val dates = arrayOf("22 September 1792", "20 May 1795", "15 July 1799", "23 September 1803", "31 December 1805", "18 March 1871", "25 August 1944", "19 September 2016", "22 September 2017", "28 September 2017") val frcDates = Array<String>(dates.size) { "" } for ((i, date) in dates.withIndex()) { val thisDate = LocalDate.parse(date, formatter) val frcd = thisDate.toFrenchRCDate() frcDates[i] = frcd.toString() println("${date.padEnd(25)} => $frcd") }   // now process the other way around println() for (frcDate in frcDates) { val thisDate = FrenchRCDate.parse(frcDate) val lds = formatter.format(thisDate.toLocalDate()) println("${frcDate.padEnd(25)} => $lds") } }