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|---|---|---|---|---|---|
http://rosettacode.org/wiki/Return_multiple_values
|
Return multiple values
|
Task
Show how to return more than one value from a function.
|
#Retro
|
Retro
|
: addSubtract ( xy-nm )
2over - [ + ] dip ;
|
http://rosettacode.org/wiki/Remove_duplicate_elements
|
Remove duplicate elements
|
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
|
#Frink
|
Frink
|
b = [1, 5, 2, 6, 6, 2, 2, 1, 9, 8, 6, 5]
// One way, using OrderedList. An OrderedList is a type of array that keeps
// its elements in order. The items must be comparable.
a = new OrderedList
println[a.insertAllUnique[b]]
// Another way, using the "set" datatype and back to an array.
println[toArray[toSet[b]]
|
http://rosettacode.org/wiki/Recaman%27s_sequence
|
Recaman's sequence
|
The Recamán's sequence generates Natural numbers.
Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated.
If the conditions don't hold then a(n) = a(n-1) + n.
Task
Generate and show here the first 15 members of the sequence.
Find and show here, the first duplicated number in the sequence.
Optionally: Find and show here, how many terms of the sequence are needed until all the integers 0..1000, inclusive, are generated.
References
A005132, The On-Line Encyclopedia of Integer Sequences.
The Slightly Spooky Recamán Sequence, Numberphile video.
Recamán's sequence, on Wikipedia.
|
#REXX
|
REXX
|
if z<0 then z= _ + #
else if !.z then z= _ + #
|
http://rosettacode.org/wiki/Recaman%27s_sequence
|
Recaman's sequence
|
The Recamán's sequence generates Natural numbers.
Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated.
If the conditions don't hold then a(n) = a(n-1) + n.
Task
Generate and show here the first 15 members of the sequence.
Find and show here, the first duplicated number in the sequence.
Optionally: Find and show here, how many terms of the sequence are needed until all the integers 0..1000, inclusive, are generated.
References
A005132, The On-Line Encyclopedia of Integer Sequences.
The Slightly Spooky Recamán Sequence, Numberphile video.
Recamán's sequence, on Wikipedia.
|
#Ring
|
Ring
|
load "zerolib.ring"
recaman = Z(0:50)
duplicate = 0
dup = []
recDuplicate = []
recnum = 0
see "working..." + nl
see "the first 15 Recaman's numbers are:" + nl
for n = 1 to len(recaman) - 1
if n = 1
recaman[0] = 0
add(dup,0)
see "" + recaman[0] + " "
ok
recaman[n] = recaman[n-1] - n
if recaman[n] <= 0
recaman[n] = recaman[n-1] + n
ok
fnrec = find(dup,recaman[n])
if fnrec > 0
del(dup,fnrec)
recaman[n] = recaman[n-1] + n
add(dup,recaman[n])
else
add(dup,recaman[n])
ok
recnum = recnum + 1
if recnum < 15
see "" + recaman[n] + " "
ok
add(recDuplicate,recaman[n])
next
see nl
see "the first duplicated term is a["
for n = len(recDuplicate) to 2 step -1
for m = n-1 to 1 step -1
if recDuplicate[n] = recDuplicate[m]
duplicate = recDuplicate[n]
dupnr = n
ok
next
next
see "" + dupnr + "] = " + duplicate + nl
see "done..." + nl
|
http://rosettacode.org/wiki/Reduced_row_echelon_form
|
Reduced row echelon form
|
Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this will probably be a two-dimensional array).
Built-in functions or this pseudocode (from Wikipedia) may be used:
function ToReducedRowEchelonForm(Matrix M) is
lead := 0
rowCount := the number of rows in M
columnCount := the number of columns in M
for 0 ≤ r < rowCount do
if columnCount ≤ lead then
stop
end if
i = r
while M[i, lead] = 0 do
i = i + 1
if rowCount = i then
i = r
lead = lead + 1
if columnCount = lead then
stop
end if
end if
end while
Swap rows i and r
If M[r, lead] is not 0 divide row r by M[r, lead]
for 0 ≤ i < rowCount do
if i ≠ r do
Subtract M[i, lead] multiplied by row r from row i
end if
end for
lead = lead + 1
end for
end function
For testing purposes, the RREF of this matrix:
1 2 -1 -4
2 3 -1 -11
-2 0 -3 22
is:
1 0 0 -8
0 1 0 1
0 0 1 -2
|
#M2000_Interpreter
|
M2000 Interpreter
|
Module Base1 {
dim base 1, A(3, 4)
A(1, 1)= 1, 2, -1, -4, 2 , 3, -1, -11, -2 , 0 , -3, 22
lead=1
rowcount=3
columncount=4
gosub disp()
for r=1 to rowcount {
if columncount<lead then exit
i=r
while A(i,lead)=0 {
i++
if rowcount=i then i=r : lead++ : if columncount<lead then exit
}
for c =1 to columncount {
swap A(i, c), A(r, c)
}
if A(r, lead)<>0 then {
div1=A(r,lead)
For c =1 to columncount {
A( r, c)/=div1
}
}
for i=1 to rowcount {
if i<>r then {
mult=A(i,lead)
for j=1 to columncount {
A(i,j)-=A(r,j)*mult
}
}
}
lead=lead+1
}
disp()
sub disp()
local i, j
for i=1 to rowcount
for j=1 to columncount
Print A(i, j),
Next j
if pos>0 then print
Next i
End sub
}
Base1
|
http://rosettacode.org/wiki/Real_constants_and_functions
|
Real constants and functions
|
Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
|
#HicEst
|
HicEst
|
e ! Not available. Can be calculated EXP(1)
pi ! Not available. Can be calculated 4.0*ATAN(1.0)
x^0.5 ! square root
LOG(x) ! natural logarithm
LOG(x, 10) ! logarithm to base 10
EXP(x) ! exponential
ABS(x) ! absolute value
FLOOR(x) ! floor
CEILING(x) ! ceiling
x**y ! x raised to the y power
x^y ! same as x**y
|
http://rosettacode.org/wiki/Remove_lines_from_a_file
|
Remove lines from a file
|
Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remove the first two lines from the file foobar.txt, the parameters should be: foobar.txt, 1, 2
Empty lines are considered and should still be counted, and if the specified line is empty, it should still be removed.
An appropriate message should appear if an attempt is made to remove lines beyond the end of the file.
|
#Python
|
Python
|
#!/usr/bin/env python
import fileinput, sys
fname, start, count = sys.argv[1:4]
start, count = int(start), int(count)
for line in fileinput.input(fname, inplace=1, backup='.orig'):
if start <= fileinput.lineno() < start + count:
pass
else:
print line.rstrip("\n")
fileinput.close()
|
http://rosettacode.org/wiki/Read_entire_file
|
Read entire file
|
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
|
#KAP
|
KAP
|
content ← io:readFile "file.txt"
|
http://rosettacode.org/wiki/Read_entire_file
|
Read entire file
|
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
|
#Kotlin
|
Kotlin
|
import java.io.File
fun main(args: Array<String>) {
println(File("unixdict.txt").readText(charset = Charsets.UTF_8))
}
|
http://rosettacode.org/wiki/Rep-string
|
Rep-string
|
Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For example, the string 10011001100 is a rep-string as the leftmost four characters of 1001 are repeated three times and truncated on the right to give the original string.
Note that the requirement for having the repeat occur two or more times means that the repeating unit is never longer than half the length of the input string.
Task
Write a function/subroutine/method/... that takes a string and returns an indication of if it is a rep-string and the repeated string. (Either the string that is repeated, or the number of repeated characters would suffice).
There may be multiple sub-strings that make a string a rep-string - in that case an indication of all, or the longest, or the shortest would suffice.
Use the function to indicate the repeating substring if any, in the following:
1001110011
1110111011
0010010010
1010101010
1111111111
0100101101
0100100
101
11
00
1
Show your output on this page.
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
|
#REXX
|
REXX
|
/* REXX ***************************************************************
* 11.05.2013 Walter Pachl
* 14.05.2013 Walter Pachl extend to show additional rep-strings
**********************************************************************/
Call repstring '1001110011'
Call repstring '1110111011'
Call repstring '0010010010'
Call repstring '1010101010'
Call repstring '1111111111'
Call repstring '0100101101'
Call repstring '0100100'
Call repstring '101'
Call repstring '11'
Call repstring '00'
Call repstring '1'
Exit
repstring:
Parse Arg s
sq=''''s''''
n=length(s)
Do l=length(s)%2 to 1 By -1
If substr(s,l+1,l)=left(s,l) Then Leave
End
If l>0 Then Do
rep_str=left(s,l)
Do i=1 By 1
If substr(s,i*l+1,l)<>rep_str Then
Leave
End
If left(copies(rep_str,n),length(s))=s Then Do
Call show_rep rep_str /* show result */
Do i=length(rep_str)-1 To 1 By -1 /* look for shorter rep_str-s */
rep_str=left(s,i)
If left(copies(rep_str,n),length(s))=s Then
Call show_rep rep_str
End
End
Else
Call show_norep
End
Else
Call show_norep
Return
show_rep:
Parse Arg rs
Say right(sq,12) 'has a repetition length of' length(rs) 'i.e.' ''''rs''''
Return
show_norep:
Say right(sq,12) 'is not a repeated string'
Return
|
http://rosettacode.org/wiki/Regular_expressions
|
Regular expressions
|
Task
match a string against a regular expression
substitute part of a string using a regular expression
|
#Python
|
Python
|
import re
string = "This is a string"
if re.search('string$', string):
print("Ends with string.")
string = re.sub(" a ", " another ", string)
print(string)
|
http://rosettacode.org/wiki/Reverse_a_string
|
Reverse a string
|
Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
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
|
#D
|
D
|
void main() {
import std.range, std.conv;
string s1 = "hello"; // UTF-8
assert(s1.retro.text == "olleh");
wstring s2 = "hello"w; // UTF-16
assert(s2.retro.wtext == "olleh"w);
dstring s3 = "hello"d; // UTF-32
assert(s3.retro.dtext == "olleh"d);
// without using std.range:
dstring s4 = "hello"d;
assert(s4.dup.reverse == "olleh"d); // simple but inefficient (copies first, then reverses)
}
|
http://rosettacode.org/wiki/Rename_a_file
|
Rename a file
|
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type systems, only the user root would have
sufficient permissions in the filesystem root.)
|
#Ruby
|
Ruby
|
File.rename('input.txt', 'output.txt')
File.rename('/input.txt', '/output.txt')
File.rename('docs', 'mydocs')
File.rename('/docs', '/mydocs')
|
http://rosettacode.org/wiki/Rename_a_file
|
Rename a file
|
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type systems, only the user root would have
sufficient permissions in the filesystem root.)
|
#Run_BASIC
|
Run BASIC
|
a$ = shell$("RENAME input.txt output.txt")
a$ = shell$("RENAME docs mydocs")
a$ = shell$("RENAME \input.txt \output.txt")
a$ = shell$("RENAME \docs \mydocs")
|
http://rosettacode.org/wiki/Reverse_words_in_a_string
|
Reverse words in a string
|
Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
|
#Quackery
|
Quackery
|
' [ $ " ---------- Ice and Fire ------------ "
$ ""
$ " fire, in end will world the say Some "
$ " ice. in say Some "
$ " desire of tasted I've what From "
$ " fire. favor who those with hold I "
$ ""
$ " ... elided paragraph last ... "
$ ""
$ " Frost Robert ----------------------- " ]
witheach
[ do nest$ reverse
witheach
[ echo$ sp ]
cr ]
|
http://rosettacode.org/wiki/Reverse_words_in_a_string
|
Reverse words in a string
|
Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
|
#R
|
R
|
whack <- function(s) {
paste( rev( unlist(strsplit(s, " "))), collapse=' ' ) }
poem <- unlist( strsplit(
'------------ Eldorado ----------
... here omitted lines ...
Mountains the "Over
Moon, the Of
Shadow, the of Valley the Down
ride," boldly Ride,
replied,--- shade The
Eldorado!" for seek you "If
Poe Edgar -----------------------', "\n"))
for (line in poem) cat( whack(line), "\n" )
|
http://rosettacode.org/wiki/Rot-13
|
Rot-13
|
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of input contained in each file listed on its command line, or (if no filenames are passed thereon) acting as a filter on its "standard input."
(A number of UNIX scripting languages and utilities, such as awk and sed either default to processing files in this way or have command line switches or modules to easily implement these wrapper semantics, e.g., Perl and Python).
The rot-13 encoding is commonly known from the early days of Usenet "Netnews" as a way of obfuscating text to prevent casual reading of spoiler or potentially offensive material.
Many news reader and mail user agent programs have built-in rot-13 encoder/decoders or have the ability to feed a message through any external utility script for performing this (or other) actions.
The definition of the rot-13 function is to simply replace every letter of the ASCII alphabet with the letter which is "rotated" 13 characters "around" the 26 letter alphabet from its normal cardinal position (wrapping around from z to a as necessary).
Thus the letters abc become nop and so on.
Technically rot-13 is a "mono-alphabetic substitution cipher" with a trivial "key".
A proper implementation should work on upper and lower case letters, preserve case, and pass all non-alphabetic characters
in the input stream through without alteration.
Related tasks
Caesar cipher
Substitution Cipher
Vigenère Cipher/Cryptanalysis
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
|
#TorqueScript
|
TorqueScript
|
function rot13(%string)
{
%alph = "abcdefghijklmnopqrstuvwxyz";
%len = strLen(%string);
for(%a = 0; %a < %len; %a++)
{
%char = getSubStr(%string,%a,1);
%pos = striPos(%alph, %char);
if(%pos < 0)
%out = %out @ %char;
else
{
if(strPos(%alph, %char) < 0)
%out = %out @ strUpr(getSubStr(%alph, (%pos + 13) % 26));
else
%out = %out @ getSubStr(%alph, (%pos + 13) % 26);
}
}
return %out;
}
|
http://rosettacode.org/wiki/Roman_numerals/Encode
|
Roman numerals/Encode
|
Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numerals:
1990 is rendered: 1000=M, 900=CM, 90=XC; resulting in MCMXC
2008 is written as 2000=MM, 8=VIII; or MMVIII
1666 uses each Roman symbol in descending order: MDCLXVI
|
#Swift
|
Swift
|
func ator(var n: Int) -> String {
var result = ""
for (value, letter) in
[( 1000, "M"),
( 900, "CM"),
( 500, "D"),
( 400, "CD"),
( 100, "C"),
( 90, "XC"),
( 50, "L"),
( 40, "XL"),
( 10, "X"),
( 9, "IX"),
( 5, "V"),
( 4, "IV"),
( 1, "I")]
{
while n >= value {
result += letter
n -= value
}
}
return result
}
|
http://rosettacode.org/wiki/Repeat_a_string
|
Repeat a string
|
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
|
#Idris
|
Idris
|
strRepeat : Nat -> String -> String
strRepeat Z s = ""
strRepeat (S n) s = s ++ strRepeat n s
chrRepeat : Nat -> Char -> String
chrRepeat Z c = ""
chrRepeat (S n) c = strCons c $ chrRepeat n c
|
http://rosettacode.org/wiki/Repeat_a_string
|
Repeat a string
|
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
|
#Inform_7
|
Inform 7
|
Home is a room.
To decide which indexed text is (T - indexed text) repeated (N - number) times:
let temp be indexed text;
repeat with M running from 1 to N:
let temp be "[temp][T]";
decide on temp.
When play begins:
say "ha" repeated 5 times;
end the story.
|
http://rosettacode.org/wiki/Return_multiple_values
|
Return multiple values
|
Task
Show how to return more than one value from a function.
|
#REXX
|
REXX
|
/*REXX program shows and displays examples of multiple RETURN values from a function.*/
numeric digits 70 /*the default is: NUMERIC DIGITS 9 */
parse arg a b . /*obtain two numbers from command line.*/
if a=='' | a=="," then a= 82 /*Not specified? Then use the default.*/
if b=='' | b=="," then b= 20 /* " " " " " " */
say ' a =' a /*display the first number to the term.*/
say ' b =' b /* " " second " " " " */
say copies('═', 50) /*display a separator line " " " */
z= arithmetics(a, b) /*call the function: arithmetics */
parse var z abut sum diff rem div Idiv prod pow /*obtain the function's returned values*/
say ' || =' abut /*display abutment to the terminal.*/
say ' + =' sum /* " sum " " " */
say ' - =' diff /* " difference " " " */
say ' // =' rem /* " remainder " " " */
say ' / =' div /* " quotient " " " */
say ' % =' Idiv /* " int. quotient " " " */
say ' * =' prod /* " product " " " */
say ' ** =' pow /* " power " " " */
exit /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
arithmetics: procedure; parse arg x,y; return x||y x+y x-y x//y x/y x%y x*y x**y
|
http://rosettacode.org/wiki/Remove_duplicate_elements
|
Remove duplicate elements
|
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
|
#Gambas
|
Gambas
|
Public Sub Main()
Dim sString As String[] = Split("Now is the time for all the good men to come to the aid of the good party 1 2 1 3 3 3 2 1 1 2 3 4 33 2 5 4 333 5", " ")
Dim sFix As New String[]
Dim sTemp As String
For Each sTemp In sString
sTemp &= " "
If InStr(sFix.Join(" ") & " ", sTemp) Then Continue
sFix.Add(Trim(sTemp))
Next
Print sFix.Join(" ")
End
|
http://rosettacode.org/wiki/Recaman%27s_sequence
|
Recaman's sequence
|
The Recamán's sequence generates Natural numbers.
Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated.
If the conditions don't hold then a(n) = a(n-1) + n.
Task
Generate and show here the first 15 members of the sequence.
Find and show here, the first duplicated number in the sequence.
Optionally: Find and show here, how many terms of the sequence are needed until all the integers 0..1000, inclusive, are generated.
References
A005132, The On-Line Encyclopedia of Integer Sequences.
The Slightly Spooky Recamán Sequence, Numberphile video.
Recamán's sequence, on Wikipedia.
|
#Ruby
|
Ruby
|
require 'set'
a = [0]
used = Set[0]
used1000 = Set[0]
foundDup = false
n = 1
while n <= 15 or not foundDup or used1000.size < 1001
nxt = a[n - 1] - n
if nxt < 1 or used === nxt then
nxt = nxt + 2 * n
end
alreadyUsed = used === nxt
a << nxt
if not alreadyUsed then
used << nxt
if nxt >= 0 and nxt <= 1000 then
used1000 << nxt
end
end
if n == 14 then
print "The first 15 terms of the Recaman's sequence are ", a, "\n"
end
if not foundDup and alreadyUsed then
print "The first duplicated term is a[", n, "] = ", nxt, "\n"
foundDup = true
end
if used1000.size == 1001 then
print "Terms up to a[", n, "] are needed to generate 0 to 1000\n"
end
n = n + 1
end
|
http://rosettacode.org/wiki/Reduced_row_echelon_form
|
Reduced row echelon form
|
Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this will probably be a two-dimensional array).
Built-in functions or this pseudocode (from Wikipedia) may be used:
function ToReducedRowEchelonForm(Matrix M) is
lead := 0
rowCount := the number of rows in M
columnCount := the number of columns in M
for 0 ≤ r < rowCount do
if columnCount ≤ lead then
stop
end if
i = r
while M[i, lead] = 0 do
i = i + 1
if rowCount = i then
i = r
lead = lead + 1
if columnCount = lead then
stop
end if
end if
end while
Swap rows i and r
If M[r, lead] is not 0 divide row r by M[r, lead]
for 0 ≤ i < rowCount do
if i ≠ r do
Subtract M[i, lead] multiplied by row r from row i
end if
end for
lead = lead + 1
end for
end function
For testing purposes, the RREF of this matrix:
1 2 -1 -4
2 3 -1 -11
-2 0 -3 22
is:
1 0 0 -8
0 1 0 1
0 0 1 -2
|
#Maple
|
Maple
|
with(LinearAlgebra):
ReducedRowEchelonForm(<<1,2,-2>|<2,3,0>|<-1,-1,-3>|<-4,-11,22>>);
|
http://rosettacode.org/wiki/Real_constants_and_functions
|
Real constants and functions
|
Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
|
#Icon_and_Unicon
|
Icon and Unicon
|
link numbers # for floor and ceil
procedure main()
write("e=",&e)
write("pi=",&pi)
write("phi=",&phi)
write("sqrt(2)=",sqrt(2.0))
write("log(e)=",log(&e))
write("log(100.,10)=",log(100,10))
write("exp(1)=",exp(1.0))
write("abs(-2)=",abs(-2))
write("floor(-2.2)=",floor(-2.2))
write("ceil(-2.2)=",ceil(-2.2))
write("power: 3^3=",3^3)
end
|
http://rosettacode.org/wiki/Remove_lines_from_a_file
|
Remove lines from a file
|
Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remove the first two lines from the file foobar.txt, the parameters should be: foobar.txt, 1, 2
Empty lines are considered and should still be counted, and if the specified line is empty, it should still be removed.
An appropriate message should appear if an attempt is made to remove lines beyond the end of the file.
|
#Racket
|
Racket
|
#lang racket
(define (remove-lines file from num)
(define lines (file->lines file))
(define-values [pfx rest] (split-at lines (sub1 from)))
(display-lines-to-file (append pfx (drop rest num)) file #:exists 'replace))
|
http://rosettacode.org/wiki/Remove_lines_from_a_file
|
Remove lines from a file
|
Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remove the first two lines from the file foobar.txt, the parameters should be: foobar.txt, 1, 2
Empty lines are considered and should still be counted, and if the specified line is empty, it should still be removed.
An appropriate message should appear if an attempt is made to remove lines beyond the end of the file.
|
#Raku
|
Raku
|
sub MAIN ($filename, $beg, $len) {
my @lines = split /^^/, slurp $filename;
unlink $filename; # or rename
splice(@lines,$beg,$len) == $len or warn "Too few lines";
spurt $filename, @lines;
}
|
http://rosettacode.org/wiki/Read_entire_file
|
Read entire file
|
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
|
#LabVIEW
|
LabVIEW
|
'foo.txt slurp
|
http://rosettacode.org/wiki/Read_entire_file
|
Read entire file
|
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
|
#Lang5
|
Lang5
|
'foo.txt slurp
|
http://rosettacode.org/wiki/Rep-string
|
Rep-string
|
Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For example, the string 10011001100 is a rep-string as the leftmost four characters of 1001 are repeated three times and truncated on the right to give the original string.
Note that the requirement for having the repeat occur two or more times means that the repeating unit is never longer than half the length of the input string.
Task
Write a function/subroutine/method/... that takes a string and returns an indication of if it is a rep-string and the repeated string. (Either the string that is repeated, or the number of repeated characters would suffice).
There may be multiple sub-strings that make a string a rep-string - in that case an indication of all, or the longest, or the shortest would suffice.
Use the function to indicate the repeating substring if any, in the following:
1001110011
1110111011
0010010010
1010101010
1111111111
0100101101
0100100
101
11
00
1
Show your output on this page.
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
|
#Ring
|
Ring
|
# Project : Rep-string
test = ["1001110011",
"1110111011",
"0010010010",
"1010101010",
"1111111111",
"0100101101",
"0100100",
"101",
"11",
"00",
"1"]
for n = 1 to len(test)
strend = ""
for m=1 to len(test[n])
strbegin = substr(test[n], 1, m)
strcut = right(test[n], len(test[n]) - m)
nr = substr(strcut, strbegin)
if nr=1 and len(test[n]) > 1
strend = strbegin
ok
next
if strend = ""
see "" + test[n] + " -> (none)" + nl
else
see "" + test[n] + " -> " + strend + nl
ok
next
|
http://rosettacode.org/wiki/Rep-string
|
Rep-string
|
Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For example, the string 10011001100 is a rep-string as the leftmost four characters of 1001 are repeated three times and truncated on the right to give the original string.
Note that the requirement for having the repeat occur two or more times means that the repeating unit is never longer than half the length of the input string.
Task
Write a function/subroutine/method/... that takes a string and returns an indication of if it is a rep-string and the repeated string. (Either the string that is repeated, or the number of repeated characters would suffice).
There may be multiple sub-strings that make a string a rep-string - in that case an indication of all, or the longest, or the shortest would suffice.
Use the function to indicate the repeating substring if any, in the following:
1001110011
1110111011
0010010010
1010101010
1111111111
0100101101
0100100
101
11
00
1
Show your output on this page.
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
|
#Ruby
|
Ruby
|
ar = %w(1001110011
1110111011
0010010010
1010101010
1111111111
0100101101
0100100
101
11
00
1)
ar.each do |str|
rep_pos = (str.size/2).downto(1).find{|pos| str.start_with? str[pos..-1]}
puts str, rep_pos ? " "*rep_pos + str[0, rep_pos] : "(no repetition)", ""
end
|
http://rosettacode.org/wiki/Regular_expressions
|
Regular expressions
|
Task
match a string against a regular expression
substitute part of a string using a regular expression
|
#R
|
R
|
pattern <- "string"
text1 <- "this is a matching string"
text2 <- "this does not match"
|
http://rosettacode.org/wiki/Regular_expressions
|
Regular expressions
|
Task
match a string against a regular expression
substitute part of a string using a regular expression
|
#Racket
|
Racket
|
#lang racket
(define s "I am a string")
(when (regexp-match? #rx"string$" s)
(displayln "Ends with 'string'."))
(unless (regexp-match? #rx"^You" s)
(displayln "Does not start with 'You'."))
(displayln (regexp-replace " a " s " another "))
|
http://rosettacode.org/wiki/Reverse_a_string
|
Reverse a string
|
Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
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
|
#Dart
|
Dart
|
String reverse(String s) => new String.fromCharCodes(s.runes.toList().reversed);
|
http://rosettacode.org/wiki/Rename_a_file
|
Rename a file
|
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type systems, only the user root would have
sufficient permissions in the filesystem root.)
|
#Rust
|
Rust
|
use std::fs;
fn main() {
let err = "File move error";
fs::rename("input.txt", "output.txt").ok().expect(err);
fs::rename("docs", "mydocs").ok().expect(err);
fs::rename("/input.txt", "/output.txt").ok().expect(err);
fs::rename("/docs", "/mydocs").ok().expect(err);
}
|
http://rosettacode.org/wiki/Rename_a_file
|
Rename a file
|
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type systems, only the user root would have
sufficient permissions in the filesystem root.)
|
#Scala
|
Scala
|
import scala.language.implicitConversions
import java.io.File
object Rename0 {
def main(args: Array[String]) { // The implicit causes every String to File mapping,
implicit def file(s: String) = new File(s) // will be converted to new File(String)
"myfile.txt" renameTo "anotherfile.txt"
"/tmp/myfile.txt" renameTo "/tmp/anotherfile.txt"
"mydir" renameTo "anotherdir"
"/tmp/mydir" renameTo "/tmp/anotherdir"
}
}
|
http://rosettacode.org/wiki/Reverse_words_in_a_string
|
Reverse words in a string
|
Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
|
#Racket
|
Racket
|
#lang racket/base
(require racket/string)
(define (split-reverse str)
(string-join
(reverse
(string-split str))))
(define poem
"---------- Ice and Fire ------------
fire, in end will world the say Some
ice. in say Some
desire of tasted I've what From
fire. favor who those with hold I
... elided paragraph last ...
Frost Robert -----------------------")
(let ([poem-port (open-input-string poem)])
(let loop ([l (read-line poem-port)])
(unless (eof-object? l)
(begin (displayln (split-reverse l))
(loop (read-line poem-port))))))
|
http://rosettacode.org/wiki/Rot-13
|
Rot-13
|
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of input contained in each file listed on its command line, or (if no filenames are passed thereon) acting as a filter on its "standard input."
(A number of UNIX scripting languages and utilities, such as awk and sed either default to processing files in this way or have command line switches or modules to easily implement these wrapper semantics, e.g., Perl and Python).
The rot-13 encoding is commonly known from the early days of Usenet "Netnews" as a way of obfuscating text to prevent casual reading of spoiler or potentially offensive material.
Many news reader and mail user agent programs have built-in rot-13 encoder/decoders or have the ability to feed a message through any external utility script for performing this (or other) actions.
The definition of the rot-13 function is to simply replace every letter of the ASCII alphabet with the letter which is "rotated" 13 characters "around" the 26 letter alphabet from its normal cardinal position (wrapping around from z to a as necessary).
Thus the letters abc become nop and so on.
Technically rot-13 is a "mono-alphabetic substitution cipher" with a trivial "key".
A proper implementation should work on upper and lower case letters, preserve case, and pass all non-alphabetic characters
in the input stream through without alteration.
Related tasks
Caesar cipher
Substitution Cipher
Vigenère Cipher/Cryptanalysis
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
|
#TXR
|
TXR
|
@(deffilter rot13
("a" "n") ("b" "o") ("c" "p") ("d" "q") ("e" "r") ("f" "s") ("g" "t")
("h" "u") ("i" "v") ("j" "w") ("k" "x") ("l" "y") ("m" "z") ("n" "a")
("o" "b") ("p" "c") ("q" "d") ("r" "e") ("s" "f") ("t" "g") ("u" "h")
("v" "i") ("w" "j") ("x" "k") ("y" "l") ("z" "m")
("A" "N") ("B" "O") ("C" "P") ("D" "Q") ("E" "R") ("F" "S") ("G" "T")
("H" "U") ("I" "V") ("J" "W") ("K" "X") ("L" "Y") ("M" "Z") ("N" "A")
("O" "B") ("P" "C") ("Q" "D") ("R" "E") ("S" "F") ("T" "G") ("U" "H")
("V" "I") ("W" "J") ("X" "K") ("Y" "L") ("Z" "M"))
@(repeat)
@line
@ (output :filter rot13)
@line
@ (end)
@(end)
|
http://rosettacode.org/wiki/Roman_numerals/Encode
|
Roman numerals/Encode
|
Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numerals:
1990 is rendered: 1000=M, 900=CM, 90=XC; resulting in MCMXC
2008 is written as 2000=MM, 8=VIII; or MMVIII
1666 uses each Roman symbol in descending order: MDCLXVI
|
#Tailspin
|
Tailspin
|
def digits: [(M:1000"1"), (CM:900"1"), (D:500"1"), (CD:400"1"), (C:100"1"), (XC:90"1"), (L:50"1"), (XL:40"1"), (X:10"1"), (IX:9"1"), (V:5"1"), (IV:4"1"), (I:1"1")];
templates encodeRoman
@: 1;
'$ -> #;' !
when <$digits($@)::value..> do
$digits($@)::key !
$ - $digits($@)::value -> #
when <1..> do
@:$@ + 1;
$ -> #
end encodeRoman
1990 -> encodeRoman -> !OUT::write
'
' -> !OUT::write
2008 -> encodeRoman -> !OUT::write
'
' -> !OUT::write
1666 -> encodeRoman -> !OUT::write
|
http://rosettacode.org/wiki/Repeat_a_string
|
Repeat a string
|
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
|
#IS-BASIC
|
IS-BASIC
|
10 PRINT STRING$("ha",5)
100 DEF STRING$(S$,N)
105 LET ST$=""
110 FOR I=1 TO N
120 LET ST$=ST$&S$
130 NEXT
140 LET STRING$=ST$
150 END DEF
|
http://rosettacode.org/wiki/Repeat_a_string
|
Repeat a string
|
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
|
#J
|
J
|
5 # '*' NB. repeat each item 5 times
*****
5 # 'ha' NB. repeat each item 5 times
hhhhhaaaaa
5 ((* #) $ ]) 'ha' NB. repeat array 5 times
hahahahaha
5 ;@# < 'ha' NB. using boxing to treat the array as a whole
hahahahaha
|
http://rosettacode.org/wiki/Return_multiple_values
|
Return multiple values
|
Task
Show how to return more than one value from a function.
|
#Ring
|
Ring
|
Func AddSub x,y
Return [ x+y, x-y ]
|
http://rosettacode.org/wiki/Return_multiple_values
|
Return multiple values
|
Task
Show how to return more than one value from a function.
|
#Ruby
|
Ruby
|
def addsub(x, y)
[x + y, x - y]
end
|
http://rosettacode.org/wiki/Remove_duplicate_elements
|
Remove duplicate elements
|
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
|
#GAP
|
GAP
|
# Built-in, using sets (which are also lists)
a := [ 1, 2, 3, 1, [ 4 ], 5, 5, [4], 6 ];
# [ 1, 2, 3, 1, [ 4 ], 5, 5, [ 4 ], 6 ]
b := Set(a);
# [ 1, 2, 3, 5, 6, [ 4 ] ]
IsSet(b);
# true
IsList(b);
# true
|
http://rosettacode.org/wiki/Recaman%27s_sequence
|
Recaman's sequence
|
The Recamán's sequence generates Natural numbers.
Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated.
If the conditions don't hold then a(n) = a(n-1) + n.
Task
Generate and show here the first 15 members of the sequence.
Find and show here, the first duplicated number in the sequence.
Optionally: Find and show here, how many terms of the sequence are needed until all the integers 0..1000, inclusive, are generated.
References
A005132, The On-Line Encyclopedia of Integer Sequences.
The Slightly Spooky Recamán Sequence, Numberphile video.
Recamán's sequence, on Wikipedia.
|
#Scala
|
Scala
|
import scala.collection.mutable
object RecamansSequence extends App {
val (a, used) = (mutable.ArrayBuffer[Int](0), mutable.BitSet())
var (foundDup, hop, nUsed1000) = (false, 1, 0)
while (nUsed1000 < 1000) {
val _next = a(hop - 1) - hop
val next = if (_next < 1 || used.contains(_next)) _next + 2 * hop else _next
val alreadyUsed = used.contains(next)
a += next
if (!alreadyUsed) {
used.add(next)
if (next <= 1000) nUsed1000 += 1
}
if (!foundDup && alreadyUsed) {
println(s"The first duplicate term is a($hop) = $next")
foundDup = true
}
if (nUsed1000 == 1000)
println(s"Terms up to $hop are needed to generate 0 to 1000")
hop += 1
}
println(s"The first 15 terms of the Recaman sequence are : ${a.take(15)}")
}
|
http://rosettacode.org/wiki/Reduced_row_echelon_form
|
Reduced row echelon form
|
Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this will probably be a two-dimensional array).
Built-in functions or this pseudocode (from Wikipedia) may be used:
function ToReducedRowEchelonForm(Matrix M) is
lead := 0
rowCount := the number of rows in M
columnCount := the number of columns in M
for 0 ≤ r < rowCount do
if columnCount ≤ lead then
stop
end if
i = r
while M[i, lead] = 0 do
i = i + 1
if rowCount = i then
i = r
lead = lead + 1
if columnCount = lead then
stop
end if
end if
end while
Swap rows i and r
If M[r, lead] is not 0 divide row r by M[r, lead]
for 0 ≤ i < rowCount do
if i ≠ r do
Subtract M[i, lead] multiplied by row r from row i
end if
end for
lead = lead + 1
end for
end function
For testing purposes, the RREF of this matrix:
1 2 -1 -4
2 3 -1 -11
-2 0 -3 22
is:
1 0 0 -8
0 1 0 1
0 0 1 -2
|
#Mathematica.2FWolfram_Language
|
Mathematica/Wolfram Language
|
RowReduce[{{1, 2, -1, -4}, {2, 3, -1, -11}, {-2, 0, -3, 22}}]
|
http://rosettacode.org/wiki/Real_constants_and_functions
|
Real constants and functions
|
Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
|
#J
|
J
|
e =. 1x1 NB. Euler's number, specified as a numeric literal.
e =. ^ 1 NB. Euler's number, computed by exponentiation.
pi=. 1p1 NB. pi, specified as a numeric literal.
pi=. o.1 NB. pi, computed trigonometrically.
magnitude_of_x =. |x
floor_of_x =. <.x
ceiling_of_x =. >.x
natural_log_of_x =. ^.x
base_x_log_of_y =. x^.y
x_squared =. *:x NB. special form
x_squared =. x^2 NB. exponential form
square_root_of_x =. %:x NB. special form
square_root_of_x =. x^0.5 NB. exponential form
x_to_the_y_power =. x^y
|
http://rosettacode.org/wiki/Real_constants_and_functions
|
Real constants and functions
|
Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
|
#Java
|
Java
|
Math.E; //e
Math.PI; //pi
Math.sqrt(x); //square root--cube root also available (cbrt)
Math.log(x); //natural logarithm--log base 10 also available (log10)
Math.exp(x); //exponential
Math.abs(x); //absolute value
Math.floor(x); //floor
Math.ceil(x); //ceiling
Math.pow(x,y); //power
|
http://rosettacode.org/wiki/Remove_lines_from_a_file
|
Remove lines from a file
|
Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remove the first two lines from the file foobar.txt, the parameters should be: foobar.txt, 1, 2
Empty lines are considered and should still be counted, and if the specified line is empty, it should still be removed.
An appropriate message should appear if an attempt is made to remove lines beyond the end of the file.
|
#REXX
|
REXX
|
/*REXX program reads and writes a specified file and delete(s) specified record(s). */
parse arg iFID ',' N "," many . /*input FID, start of delete, how many.*/
if iFID='' then call er "no input fileID specified." /*oops.*/
if N='' then call er "no start number specified." /*oops.*/
if many='' then many=1 /*Not specified? Assume delete 1 line.*/
stop=N+many-1 /*calculate high end of delete range.*/
oFID=iFID'.$$$' /*temp name (fileID) of the output file*/
#=0 /*the count (so far) of records written*/
do j=1 while lines(iFID)\==0 /*J is the record# (line) being read.*/
@=linein(iFID) /*read a record (line) from input file.*/
if j>=N & j<=stop then iterate /*if it's in the range, then ignore it.*/
call lineout oFID,@; #=#+1 /*write record (line);, bump write cnt.*/
end /*j*/ /* [↑] by ignoring it is to delete it.*/
j=j-1 /*adjust J (because of DO loop advance)*/
if j<stop then say "The number of lines in file is less than the range given."
$='"' /*handle cases of blanks in the FID(s).*/
'ERASE' $ || iFID || $ /*erase the original file. */
'RENAME' $ || oFID || $ $ || iFID || $ /*rename " new " to original. */
say 'file ' iFID " had" j 'record's(j)", it now has" # 'record's(w)"."
exit /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
er: say; say '***error***'; say; say arg(1); say; exit 13
s: if arg(1)==1 then return arg(3); return word(arg(2) 's', 1) /*pluralizer.*/
|
http://rosettacode.org/wiki/Read_entire_file
|
Read entire file
|
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
|
#Lasso
|
Lasso
|
local(f) = file('foo.txt')
#f->readString
|
http://rosettacode.org/wiki/Read_entire_file
|
Read entire file
|
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
|
#LFE
|
LFE
|
(set `#(ok ,data) (file:read_file "myfile.txt"))
|
http://rosettacode.org/wiki/Rep-string
|
Rep-string
|
Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For example, the string 10011001100 is a rep-string as the leftmost four characters of 1001 are repeated three times and truncated on the right to give the original string.
Note that the requirement for having the repeat occur two or more times means that the repeating unit is never longer than half the length of the input string.
Task
Write a function/subroutine/method/... that takes a string and returns an indication of if it is a rep-string and the repeated string. (Either the string that is repeated, or the number of repeated characters would suffice).
There may be multiple sub-strings that make a string a rep-string - in that case an indication of all, or the longest, or the shortest would suffice.
Use the function to indicate the repeating substring if any, in the following:
1001110011
1110111011
0010010010
1010101010
1111111111
0100101101
0100100
101
11
00
1
Show your output on this page.
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
|
#Rust
|
Rust
|
fn main() {
let strings = vec![
String::from("1001110011"),
String::from("1110111011"),
String::from("0010010010"),
String::from("1010101010"),
String::from("1111111111"),
String::from("0100101101"),
String::from("0100100"),
String::from("101"),
String::from("11"),
String::from("00"),
String::from("1"),
];
for string in strings {
match rep_string(&string) {
Some(rep_string) => println!(
"Longuest rep-string for '{}' is '{}' ({} chars)",
string,
rep_string,
rep_string.len(),
),
None => println!("No rep-string found for '{}'", string),
};
}
}
fn rep_string(string: &str) -> Option<&str> {
let index = string.len() / 2;
for split_index in (1..=index).rev() {
let mut is_rep_string = true;
let (first, last) = string.split_at(split_index);
let inter = last.chars().collect::<Vec<char>>();
let mut iter = inter.chunks_exact(split_index);
for chunk in iter.by_ref() {
if first != chunk.iter().collect::<String>() {
is_rep_string = false;
break;
}
}
let rmnd = iter.remainder().iter().collect::<String>();
// Check that the remainder starts with the rep-string
if !first.starts_with(rmnd.as_str()) {
is_rep_string = false;
}
if is_rep_string {
return Some(first);
}
}
None
}
#[cfg(test)]
mod tests {
use super::rep_string;
use std::collections::HashMap;
#[test]
fn test_rep_string() {
let mut results = HashMap::new();
results.insert(String::from("1001110011"), Some("10011"));
results.insert(String::from("1110111011"), Some("1110"));
results.insert(String::from("0010010010"), Some("001"));
results.insert(String::from("1010101010"), Some("1010"));
results.insert(String::from("1111111111"), Some("11111"));
results.insert(String::from("0100101101"), None);
results.insert(String::from("0100100"), Some("010"));
results.insert(String::from("101"), None);
results.insert(String::from("11"), Some("1"));
results.insert(String::from("00"), Some("0"));
results.insert(String::from("1"), None);
for (input, expected) in results {
assert_eq!(expected, rep_string(&input));
}
}
}
|
http://rosettacode.org/wiki/Rep-string
|
Rep-string
|
Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For example, the string 10011001100 is a rep-string as the leftmost four characters of 1001 are repeated three times and truncated on the right to give the original string.
Note that the requirement for having the repeat occur two or more times means that the repeating unit is never longer than half the length of the input string.
Task
Write a function/subroutine/method/... that takes a string and returns an indication of if it is a rep-string and the repeated string. (Either the string that is repeated, or the number of repeated characters would suffice).
There may be multiple sub-strings that make a string a rep-string - in that case an indication of all, or the longest, or the shortest would suffice.
Use the function to indicate the repeating substring if any, in the following:
1001110011
1110111011
0010010010
1010101010
1111111111
0100101101
0100100
101
11
00
1
Show your output on this page.
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
|
#Scala
|
Scala
|
object RepString extends App {
def repsOf(s: String) = s.trim match {
case s if s.length < 2 => Nil
case s => (1 to (s.length/2)).map(s take _)
.filter(_ * s.length take s.length equals s)
}
val tests = Array(
"1001110011",
"1110111011",
"0010010010",
"1010101010",
"1111111111",
"0100101101",
"0100100",
"101",
"11",
"00",
"1"
)
def printReps(s: String) = repsOf(s) match {
case Nil => s+": NO"
case r => s+": YES ("+r.mkString(", ")+")"
}
val todo = if (args.length > 0) args else tests
todo.map(printReps).foreach(println)
}
|
http://rosettacode.org/wiki/Regular_expressions
|
Regular expressions
|
Task
match a string against a regular expression
substitute part of a string using a regular expression
|
#Raku
|
Raku
|
if 'a long string' ~~ /string$/ {
say "It ends with 'string'";
}
# substitution has a few nifty features
$_ = 'The quick Brown fox';
s:g:samecase/\w+/xxx/;
.say;
# output:
# Xxx xxx Xxx xxx
|
http://rosettacode.org/wiki/Reverse_a_string
|
Reverse a string
|
Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
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
|
#DBL
|
DBL
|
K=
STR_OUT=
FOR J=%TRIM(STR_IN) STEP -1 UNTIL 1
DO BEGIN
INCR K
STR_OUT(K:1)=STR_IN(J:1)
END
|
http://rosettacode.org/wiki/Rename_a_file
|
Rename a file
|
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type systems, only the user root would have
sufficient permissions in the filesystem root.)
|
#Scheme
|
Scheme
|
(rename-file "input.txt" "output.txt")
(rename-file "docs" "mydocs")
(rename-file "/input.txt" "/output.txt")
(rename-file "/docs" "/mydocs")
|
http://rosettacode.org/wiki/Rename_a_file
|
Rename a file
|
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type systems, only the user root would have
sufficient permissions in the filesystem root.)
|
#Seed7
|
Seed7
|
$ include "seed7_05.s7i";
include "osfiles.s7i";
const proc: main is func
begin
moveFile("input.txt", "output.txt");
moveFile("docs", "mydocs");
moveFile("/input.txt", "/output.txt");
moveFile("/docs", "/mydocs");
end func;
|
http://rosettacode.org/wiki/Reverse_words_in_a_string
|
Reverse words in a string
|
Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
|
#Raku
|
Raku
|
say ~.words.reverse for lines
|
http://rosettacode.org/wiki/Rot-13
|
Rot-13
|
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of input contained in each file listed on its command line, or (if no filenames are passed thereon) acting as a filter on its "standard input."
(A number of UNIX scripting languages and utilities, such as awk and sed either default to processing files in this way or have command line switches or modules to easily implement these wrapper semantics, e.g., Perl and Python).
The rot-13 encoding is commonly known from the early days of Usenet "Netnews" as a way of obfuscating text to prevent casual reading of spoiler or potentially offensive material.
Many news reader and mail user agent programs have built-in rot-13 encoder/decoders or have the ability to feed a message through any external utility script for performing this (or other) actions.
The definition of the rot-13 function is to simply replace every letter of the ASCII alphabet with the letter which is "rotated" 13 characters "around" the 26 letter alphabet from its normal cardinal position (wrapping around from z to a as necessary).
Thus the letters abc become nop and so on.
Technically rot-13 is a "mono-alphabetic substitution cipher" with a trivial "key".
A proper implementation should work on upper and lower case letters, preserve case, and pass all non-alphabetic characters
in the input stream through without alteration.
Related tasks
Caesar cipher
Substitution Cipher
Vigenère Cipher/Cryptanalysis
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
|
#UNIX_Shell
|
UNIX Shell
|
tr \
'NOWHERE AZ clerk IRAQ faber gnat ABJURER NM pyrex VEND snore tang'\
'abjurer nm PYREX vend SNORE TANG nowhere az CLERK iraq FABER GNAT' \
'ABJURER NM pyrex VEND snore tang NOWHERE AZ clerk IRAQ faber gnat'\
'nowhere az CLERK iraq FABER GNAT abjurer nm PYREX vend SNORE TANG'
|
http://rosettacode.org/wiki/Roman_numerals/Encode
|
Roman numerals/Encode
|
Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numerals:
1990 is rendered: 1000=M, 900=CM, 90=XC; resulting in MCMXC
2008 is written as 2000=MM, 8=VIII; or MMVIII
1666 uses each Roman symbol in descending order: MDCLXVI
|
#Tcl
|
Tcl
|
proc to_roman {i} {
set map {1000 M 900 CM 500 D 400 CD 100 C 90 XC 50 L 40 XL 10 X 9 IX 5 V 4 IV 1 I}
foreach {value roman} $map {
while {$i >= $value} {
append res $roman
incr i -$value
}
}
return $res
}
|
http://rosettacode.org/wiki/Repeat_a_string
|
Repeat a string
|
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
|
#Java
|
Java
|
public static String repeat(String str, int times) {
StringBuilder sb = new StringBuilder(str.length() * times);
for (int i = 0; i < times; i++)
sb.append(str);
return sb.toString();
}
public static void main(String[] args) {
System.out.println(repeat("ha", 5));
}
|
http://rosettacode.org/wiki/Return_multiple_values
|
Return multiple values
|
Task
Show how to return more than one value from a function.
|
#Run_BASIC
|
Run BASIC
|
a$ = timeInfo$()
print " UTC:";word$(a$,1,"|")
print "Date:";word$(a$,2,"|")
print "Time:";word$(a$,3,"|")
wait
function timeInfo$()
utc$ = word$(word$(httpget$("http://tycho.usno.navy.mil/cgi-bin/timer.pl"),1,"UTC"),2,"<BR>") ' Universal time
d$ = date$()
t$ = time$()
timeInfo$ = utc$;"|";d$;"|";t$
end function
|
http://rosettacode.org/wiki/Return_multiple_values
|
Return multiple values
|
Task
Show how to return more than one value from a function.
|
#Rust
|
Rust
|
fn multi_hello() -> (&'static str, i32) {
("Hello",42)
}
fn main() {
let (str,num)=multi_hello();
println!("{},{}",str,num);
}
|
http://rosettacode.org/wiki/Remove_duplicate_elements
|
Remove duplicate elements
|
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
|
#Go
|
Go
|
package main
import "fmt"
func uniq(list []int) []int {
unique_set := make(map[int]bool, len(list))
for _, x := range list {
unique_set[x] = true
}
result := make([]int, 0, len(unique_set))
for x := range unique_set {
result = append(result, x)
}
return result
}
func main() {
fmt.Println(uniq([]int{1, 2, 3, 2, 3, 4})) // prints: [3 4 1 2] (but in a semi-random order)
}
|
http://rosettacode.org/wiki/Recaman%27s_sequence
|
Recaman's sequence
|
The Recamán's sequence generates Natural numbers.
Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated.
If the conditions don't hold then a(n) = a(n-1) + n.
Task
Generate and show here the first 15 members of the sequence.
Find and show here, the first duplicated number in the sequence.
Optionally: Find and show here, how many terms of the sequence are needed until all the integers 0..1000, inclusive, are generated.
References
A005132, The On-Line Encyclopedia of Integer Sequences.
The Slightly Spooky Recamán Sequence, Numberphile video.
Recamán's sequence, on Wikipedia.
|
#Scheme
|
Scheme
|
; Create a dynamically resizing vector (a "dynvec").
; Returns a procedure that takes a variable number of arguments:
; 0 : () --> Returns the vector from index 0 through the maximum index set.
; 1 : (inx) --> Returns the value at the given index.
; 2 : (inx val) --> Sets the given value into the given index, and returns the value.
(define make-dynvec
(lambda (init-size extra-fact init-val)
(let ((vec (make-vector init-size init-val)) (maxinx -1))
(lambda args
(if (null? args)
(let ((retvec (make-vector (1+ maxinx))))
(do ((index 0 (1+ index)))
((> index maxinx) retvec)
(vector-set! retvec index (vector-ref vec index))))
(let ((inx (car args)))
(when (>= inx (vector-length vec))
(let ((newvec (make-vector
(inexact->exact (ceiling (* extra-fact inx)))
init-val)))
(do ((index 0 (1+ index)))
((>= index (vector-length vec)))
(vector-set! newvec index (vector-ref vec index)))
(set! vec newvec)))
(when (pair? (cdr args))
(when (> inx maxinx) (set! maxinx inx))
(vector-set! vec inx (cadr args)))
(vector-ref vec inx)))))))
; Generate the Recaman's sequence.
; Generate the terms of Recaman's sequence until the given "stop" procedure
; returns a true value; that returned value becomes the value of this procedure.
; The arguments to the "stop" procedure are: n, the value of the n'th term,
; #t if that term was seen before, #t if the term was arrived at by addition,
; the Recaman's sequence so far (as a dynvec), and a dynvec of the n's at which
; a value was first seen or #f if not previously seen ("seen1st").
(define recaman-sequence
(lambda (stop-proc)
(let ((recaman (make-dynvec 10 2 0))
(seen1st (make-dynvec 10 2 #f)))
(do ((n 0 (1+ n)) (done-retval #f))
(done-retval done-retval)
(if (= n 0)
(begin
(recaman n 0)
(seen1st 0 n)
(set! done-retval (stop-proc n 0 #f #f recaman seen1st)))
(let ((try-sub (- (recaman (1- n)) n)))
(if (and (> try-sub 0) (not (seen1st try-sub)))
(begin
(recaman n try-sub)
(seen1st try-sub n)
(set! done-retval (stop-proc n try-sub #f #f recaman seen1st)))
(let* ((val-add (+ (recaman (1- n)) n)) (seen-prev (seen1st val-add)))
(recaman n val-add)
(unless (seen1st val-add) (seen1st val-add n))
(set! done-retval
(stop-proc n val-add seen-prev #t recaman seen1st))))))))))
; Generate and display the first 15 Recaman's numbers.
(printf "First 15 Recaman's numbers: ~a~%"
(recaman-sequence (lambda (n val seen-prev by-add recaman seen1st)
(and (>= n (1- 15)) (recaman)))))
; Find and display the first duplicated Recaman's number.
; The only way to be a duplicate is if the number was arrived
; at by adding 'n' and the number has been seen before.
(let ((dup-n-val-1st
(recaman-sequence (lambda (n val seen-prev by-add recaman seen1st)
(and by-add seen-prev (list n val (seen1st val)))))))
(printf "First duplicate Recaman's number: a[~a] = a[~a] = ~a~%"
(caddr dup-n-val-1st) (car dup-n-val-1st) (cadr dup-n-val-1st)))
; Find and display how many terms of the sequence are needed
; for all the integers 0..1000, inclusive, to be generated.
(let* ((all-first 1001)
(terms-to-gen-all (recaman-sequence
(lambda (n val seen-prev by-add recaman seen1st)
(do ((inx 0 (1+ inx)))
((or (>= inx all-first) (not (seen1st inx)))
(and (>= inx all-first) (1+ n))))))))
(printf
"Terms of Recaman's sequence to generate all integers 0..~a, inclusive: ~a~%"
(1- all-first) terms-to-gen-all))
|
http://rosettacode.org/wiki/Reduced_row_echelon_form
|
Reduced row echelon form
|
Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this will probably be a two-dimensional array).
Built-in functions or this pseudocode (from Wikipedia) may be used:
function ToReducedRowEchelonForm(Matrix M) is
lead := 0
rowCount := the number of rows in M
columnCount := the number of columns in M
for 0 ≤ r < rowCount do
if columnCount ≤ lead then
stop
end if
i = r
while M[i, lead] = 0 do
i = i + 1
if rowCount = i then
i = r
lead = lead + 1
if columnCount = lead then
stop
end if
end if
end while
Swap rows i and r
If M[r, lead] is not 0 divide row r by M[r, lead]
for 0 ≤ i < rowCount do
if i ≠ r do
Subtract M[i, lead] multiplied by row r from row i
end if
end for
lead = lead + 1
end for
end function
For testing purposes, the RREF of this matrix:
1 2 -1 -4
2 3 -1 -11
-2 0 -3 22
is:
1 0 0 -8
0 1 0 1
0 0 1 -2
|
#MATLAB
|
MATLAB
|
rref([1, 2, -1, -4; 2, 3, -1, -11; -2, 0, -3, 22])
|
http://rosettacode.org/wiki/Real_constants_and_functions
|
Real constants and functions
|
Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
|
#JavaScript
|
JavaScript
|
Math.E
Math.PI
Math.sqrt(x)
Math.log(x)
Math.exp(x)
Math.abs(x)
Math.floor(x)
Math.ceil(x)
Math.pow(x,y)
|
http://rosettacode.org/wiki/Remove_lines_from_a_file
|
Remove lines from a file
|
Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remove the first two lines from the file foobar.txt, the parameters should be: foobar.txt, 1, 2
Empty lines are considered and should still be counted, and if the specified line is empty, it should still be removed.
An appropriate message should appear if an attempt is made to remove lines beyond the end of the file.
|
#Ring
|
Ring
|
cStr = read("C:\Ring\bin\filename.txt")
aList = str2list(cStr)
see aList + nl
lineStart = 3
lineCount = 5
num = -1
for n = lineStart to lineStart+lineCount-1
num += 1
del(aList,n-num)
next
cStr = list2str(aList)
see cStr + nl
write("C:\Ring\bin\filename.txt",cStr)
|
http://rosettacode.org/wiki/Remove_lines_from_a_file
|
Remove lines from a file
|
Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remove the first two lines from the file foobar.txt, the parameters should be: foobar.txt, 1, 2
Empty lines are considered and should still be counted, and if the specified line is empty, it should still be removed.
An appropriate message should appear if an attempt is made to remove lines beyond the end of the file.
|
#Ruby
|
Ruby
|
require 'tempfile'
def remove_lines(filename, start, num)
tmp = Tempfile.open(filename) do |fp|
File.foreach(filename) do |line|
if $. >= start and num > 0
num -= 1
else
fp.puts line
end
end
fp
end
puts "Warning: End of file encountered before all lines removed" if num > 0
FileUtils.copy(tmp.path, filename)
tmp.unlink
end
# Test code
def setup(filename, start, remove)
puts "remove #{remove} lines starting at line #{start}"
File.open(filename, "w") {|fh| (1..5).each {|i| fh.puts " "*i + i.to_s}}
puts "before:", File.read(filename)
end
def teardown(filename)
puts "after:", File.read(filename)
puts
File.unlink(filename)
end
filename = "foobar.txt"
start = 2
[2, 6].each do |remove|
setup(filename, start, remove)
remove_lines(filename, start, remove)
teardown(filename)
end
|
http://rosettacode.org/wiki/Read_entire_file
|
Read entire file
|
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
|
#Liberty_BASIC
|
Liberty BASIC
|
filedialog "Open a Text File","*.txt",file$
if file$<>"" then
open file$ for input as #1
entire$ = input$(#1, lof(#1))
close #1
print entire$
end if
|
http://rosettacode.org/wiki/Read_entire_file
|
Read entire file
|
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
|
#Lingo
|
Lingo
|
----------------------------------------
-- Reads whole file, returns string
-- @param {string} tFile
-- @return {string|false}
----------------------------------------
on readFile (tFile)
fp = xtra("fileIO").new()
fp.openFile(tFile, 1)
if fp.status() then return false
res = fp.readFile()
fp.closeFile()
return res
end
|
http://rosettacode.org/wiki/Rep-string
|
Rep-string
|
Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For example, the string 10011001100 is a rep-string as the leftmost four characters of 1001 are repeated three times and truncated on the right to give the original string.
Note that the requirement for having the repeat occur two or more times means that the repeating unit is never longer than half the length of the input string.
Task
Write a function/subroutine/method/... that takes a string and returns an indication of if it is a rep-string and the repeated string. (Either the string that is repeated, or the number of repeated characters would suffice).
There may be multiple sub-strings that make a string a rep-string - in that case an indication of all, or the longest, or the shortest would suffice.
Use the function to indicate the repeating substring if any, in the following:
1001110011
1110111011
0010010010
1010101010
1111111111
0100101101
0100100
101
11
00
1
Show your output on this page.
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
|
#Seed7
|
Seed7
|
$ include "seed7_05.s7i";
const func integer: repeatLength (in string: text) is func
result
var integer: length is 0;
local
var integer: pos is 0;
begin
for pos range succ(length(text) div 2) downto 1 until length <> 0 do
if startsWith(text, text[pos ..]) then
length := pred(pos);
end if;
end for;
end func;
const proc: main is func
local
var string: line is "";
var integer: length is 0;
begin
for line range [] ("1001110011", "1110111011", "0010010010", "1010101010",
"1111111111", "0100101101", "0100100", "101", "11", "00", "1") do
length := repeatLength(line);
if length = 0 then
writeln("No rep-string for " <& literal(line));
else
writeln("Longest rep-string for " <& literal(line) <& ": " <& literal(line[.. length]));
end if;
end for;
end func;
|
http://rosettacode.org/wiki/Rep-string
|
Rep-string
|
Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For example, the string 10011001100 is a rep-string as the leftmost four characters of 1001 are repeated three times and truncated on the right to give the original string.
Note that the requirement for having the repeat occur two or more times means that the repeating unit is never longer than half the length of the input string.
Task
Write a function/subroutine/method/... that takes a string and returns an indication of if it is a rep-string and the repeated string. (Either the string that is repeated, or the number of repeated characters would suffice).
There may be multiple sub-strings that make a string a rep-string - in that case an indication of all, or the longest, or the shortest would suffice.
Use the function to indicate the repeating substring if any, in the following:
1001110011
1110111011
0010010010
1010101010
1111111111
0100101101
0100100
101
11
00
1
Show your output on this page.
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
|
#Sidef
|
Sidef
|
var arr = <1001110011 1110111011
0010010010 1010101010
1111111111 0100101101
0100100 101 11 00 1>;
arr.each { |n|
if (var m = /^(.+)\1+(.*$)(?(?{ substr($1, 0, length $2) eq $2 })|(?!))/.match(n)) {
var i = m[0].len;
say (n.substr(0, i),
n.substr(i, i).tr('01', '𝟘𝟙'),
n.substr(i*2));
} else {
say "#{n} (no repeat)";
}
}
|
http://rosettacode.org/wiki/Regular_expressions
|
Regular expressions
|
Task
match a string against a regular expression
substitute part of a string using a regular expression
|
#Raven
|
Raven
|
'i am a string' as str
|
http://rosettacode.org/wiki/Regular_expressions
|
Regular expressions
|
Task
match a string against a regular expression
substitute part of a string using a regular expression
|
#REBOL
|
REBOL
|
rebol [
Title: "Regular Expression Matching"
URL: http://rosettacode.org/wiki/Regular_expression_matching
]
string: "This is a string."
; REBOL doesn't use a conventional Perl-compatible regular expression
; syntax. Instead, it uses a variant Parsing Expression Grammar with
; the 'parse' function. It's also not limited to just strings. You can
; define complex grammars that actually parse and execute program
; files.
; Here, I provide a rule to 'parse' that specifies searching through
; the string until "string." is found, then the end of the string. If
; the subject string satisfies the rule, the expression will be true.
if parse string [thru "string." end] [
print "Subject ends with 'string.'"]
; For replacement, I take advantage of the ability to call arbitrary
; code when a pattern is matched -- everything in the parens will be
; executed when 'to " a "' is satisfied. This marks the current string
; location, then removes the offending word and inserts the replacement.
parse string [
to " a " ; Jump to target.
mark: (
remove/part mark 3 ; Remove target.
mark: insert mark " another " ; Insert replacement.
)
:mark ; Pick up where I left off.
]
print [crlf "Parse replacement:" string]
; For what it's worth, the above operation is more conveniently done
; with the 'replace' function:
replace string " another " " a " ; Change string back.
print [crlf "Replacement:" string]
|
http://rosettacode.org/wiki/Reverse_a_string
|
Reverse a string
|
Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
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
|
#Dc
|
Dc
|
22405534230753963835153736737 [ 256 ~ d SS 0<F LS SR 1+ ] d sF x 1 - [ 1 - d 0<F 256 * LR + ] d sF x P
|
http://rosettacode.org/wiki/Rename_a_file
|
Rename a file
|
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type systems, only the user root would have
sufficient permissions in the filesystem root.)
|
#Sidef
|
Sidef
|
# Here
File.rename('input.txt', 'output.txt');
File.rename('docs', 'mydocs');
# Root dir
File.rename(Dir.root + %f'input.txt', Dir.root + %f'output.txt');
File.rename(Dir.root + %f'docs', Dir.root + %f'mydocs');
|
http://rosettacode.org/wiki/Rename_a_file
|
Rename a file
|
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type systems, only the user root would have
sufficient permissions in the filesystem root.)
|
#Slate
|
Slate
|
(File newNamed: 'input.txt') renameTo: 'output.txt'.
(File newNamed: '/input.txt') renameTo: '/output.txt'.
(Directory newNamed: 'docs') renameTo: 'mydocs'.
(Directory newNamed: '/docs') renameTo: '/mydocs'.
|
http://rosettacode.org/wiki/Reverse_words_in_a_string
|
Reverse words in a string
|
Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
|
#Red
|
Red
|
Red []
foreach line
split
{---------- Ice and Fire ------------
fire, in end will world the say Some
ice. in say Some
desire of tasted I've what From
fire. favor who those with hold I
... elided paragraph last ...
Frost Robert -----------------------} newline [
print reverse split line " "
]
|
http://rosettacode.org/wiki/Reverse_words_in_a_string
|
Reverse words in a string
|
Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); the visible punctuation form part of the word within which it is located and should not be modified.
You may assume that there are no significant non-visible characters in the input. Multiple or superfluous spaces may be compressed into a single space.
Some strings have no tokens, so an empty string (or one just containing spaces) would be the result.
Display the strings in order (1st, 2nd, 3rd, ···), and one string per line.
(You can consider the ten strings as ten lines, and the tokens as words.)
Input data
(ten lines within the box)
line
╔════════════════════════════════════════╗
1 ║ ---------- Ice and Fire ------------ ║
2 ║ ║ ◄─── a blank line here.
3 ║ fire, in end will world the say Some ║
4 ║ ice. in say Some ║
5 ║ desire of tasted I've what From ║
6 ║ fire. favor who those with hold I ║
7 ║ ║ ◄─── a blank line here.
8 ║ ... elided paragraph last ... ║
9 ║ ║ ◄─── a blank line here.
10 ║ Frost Robert ----------------------- ║
╚════════════════════════════════════════╝
Cf.
Phrase reversals
|
#REXX
|
REXX
|
/*REXX program reverses the order of tokens in a string (but not the letters).*/
@.=; @.1 = "---------- Ice and Fire ------------"
@.2 = ' '
@.3 = "fire, in end will world the say Some"
@.4 = "ice. in say Some"
@.5 = "desire of tasted I've what From"
@.6 = "fire. favor who those with hold I"
@.7 = ' '
@.8 = "... elided paragraph last ..."
@.9 = ' '
@.10 = "Frost Robert -----------------------"
do j=1 while @.j\=='' /*process each of the 10 lines of poem.*/
$= /*nullify the $ string (the new line)*/
do k=1 for words(@.j) /*process each word in a @.j string.*/
$=word(@.j,k) $ /*prepend a word to the new line ($). */
end /*k*/ /* [↑] we could do this another way. */
say $ /*display the newly constructed line. */
end /*j*/ /*stick a fork in it, we're all done. */
|
http://rosettacode.org/wiki/Rot-13
|
Rot-13
|
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of input contained in each file listed on its command line, or (if no filenames are passed thereon) acting as a filter on its "standard input."
(A number of UNIX scripting languages and utilities, such as awk and sed either default to processing files in this way or have command line switches or modules to easily implement these wrapper semantics, e.g., Perl and Python).
The rot-13 encoding is commonly known from the early days of Usenet "Netnews" as a way of obfuscating text to prevent casual reading of spoiler or potentially offensive material.
Many news reader and mail user agent programs have built-in rot-13 encoder/decoders or have the ability to feed a message through any external utility script for performing this (or other) actions.
The definition of the rot-13 function is to simply replace every letter of the ASCII alphabet with the letter which is "rotated" 13 characters "around" the 26 letter alphabet from its normal cardinal position (wrapping around from z to a as necessary).
Thus the letters abc become nop and so on.
Technically rot-13 is a "mono-alphabetic substitution cipher" with a trivial "key".
A proper implementation should work on upper and lower case letters, preserve case, and pass all non-alphabetic characters
in the input stream through without alteration.
Related tasks
Caesar cipher
Substitution Cipher
Vigenère Cipher/Cryptanalysis
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
|
#Unlambda
|
Unlambda
|
``ci`d``@i`c``s`d```?aic.n``s`d```?bic.o``s`d```?cic.p``s`d```?dic.q``s`d```?eic
.r``s`d```?fic.s``s`d```?gic.t``s`d```?hic.u``s`d```?iic.v``s`d```?jic.w``s`d```
?kic.x``s`d```?lic.y``s`d```?mic.z``s`d```?nic.a``s`d```?oic.b``s`d```?pic.c``s`
d```?qic.d``s`d```?ric.e``s`d```?sic.f``s`d```?tic.g``s`d```?uic.h``s`d```?vic.i
``s`d```?wic.j``s`d```?xic.k``s`d```?yic.l``s`d```?zic.m``s`d```?Nic.A``s`d```?O
ic.B``s`d```?Pic.C``s`d```?Qic.D``s`d```?Ric.E``s`d```?Sic.F``s`d```?Tic.G``s`d`
``?Uic.H``s`d```?Vic.I``s`d```?Wic.J``s`d```?Xic.K``s`d```?Yic.L``s`d```?Zic.M``
s`d```?Aic.N``s`d```?Bic.O``s`d```?Cic.P``s`d```?Dic.Q``s`d```?Eic.R``s`d```?Fic
.S``s`d```?Gic.T``s`d```?Hic.U``s`d```?Iic.V``s`d```?Jic.W``s`d```?Kic.X``s`d```
?Lic.Y``s`d```?Mic.Z`d`|c
|
http://rosettacode.org/wiki/Roman_numerals/Encode
|
Roman numerals/Encode
|
Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numerals:
1990 is rendered: 1000=M, 900=CM, 90=XC; resulting in MCMXC
2008 is written as 2000=MM, 8=VIII; or MMVIII
1666 uses each Roman symbol in descending order: MDCLXVI
|
#TI-83_BASIC
|
TI-83 BASIC
|
PROGRAM:DEC2ROM
:"="→Str1
:Lbl ST
:ClrHome
:Disp "NUMBER TO"
:Disp "CONVERT:"
:Input A
:If fPart(A) or A≠abs(A)
:Then
:Goto PI
:End
:A→B
:While B≥1000
:Str1+"M"→Str1
:B-1000→B
:End
:If B≥900
:Then
:Str1+"CM"→Str1
:B-900→B
:End
:If B≥500
:Then
:Str1+"D"→Str1
:B-500→B
:End
:If B≥400
:Then
:Str1+"CD"?Str1
:B-400→B
:End
:While B≥100
:Str1+"C"→Str1
:B-100→B
:End
:If B≥90
:Then
:Str1+"XC"→Str1
:B-90→B
:End
:If B≥50
:Then
:Str1+"L"→Str1
:B-50→B
:End
:If B≥40
:Then
:Str1+"XL"→Str1
:B-40→B
:End
:While B≥10
:Str1+"X"→Str1
:B-10→B
:End
:If B≥9
:Then
:Str1+"IX"→Str1
:B-9→B
:End
:If B≥5
:Then
:Str1+"V"→Str1
:B-5→B
:End
:If B≥4
:Then
:Str1+"IV"→Str1
:B-4→B
:End
:While B>0
:Str1+"I"→Str1
:B-1→B
:End
:ClrHome
:Disp A
:Disp Str1
:Stop
:Lbl PI
:ClrHome
:Disp "THE NUMBER MUST"
:Disp "BE A POSITIVE"
:Disp "INTEGER."
:Pause
:Goto ST
|
http://rosettacode.org/wiki/Repeat_a_string
|
Repeat a string
|
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
|
#JavaScript
|
JavaScript
|
String.prototype.repeat = function(n) {
return new Array(1 + (n || 0)).join(this);
}
console.log("ha".repeat(5)); // hahahahaha
|
http://rosettacode.org/wiki/Repeat_a_string
|
Repeat a string
|
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
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
|
#jq
|
jq
|
"a " * 3' # => "a a a "
|
http://rosettacode.org/wiki/Return_multiple_values
|
Return multiple values
|
Task
Show how to return more than one value from a function.
|
#Scala
|
Scala
|
def addSubMult(x: Int, y: Int) = (x + y, x - y, x * y)
|
http://rosettacode.org/wiki/Return_multiple_values
|
Return multiple values
|
Task
Show how to return more than one value from a function.
|
#Scheme
|
Scheme
|
(define (addsub x y)
(values (+ x y) (- x y)))
|
http://rosettacode.org/wiki/Remove_duplicate_elements
|
Remove duplicate elements
|
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
O(n2) sorts
Bubble sort |
Cocktail sort |
Cocktail sort with shifting bounds |
Comb sort |
Cycle sort |
Gnome sort |
Insertion sort |
Selection sort |
Strand sort
other sorts
Bead sort |
Bogo sort |
Common sorted list |
Composite structures sort |
Custom comparator sort |
Counting sort |
Disjoint sublist sort |
External sort |
Jort sort |
Lexicographical sort |
Natural sorting |
Order by pair comparisons |
Order disjoint list items |
Order two numerical lists |
Object identifier (OID) sort |
Pancake sort |
Quickselect |
Permutation sort |
Radix sort |
Ranking methods |
Remove duplicate elements |
Sleep sort |
Stooge sort |
[Sort letters of a string] |
Three variable sort |
Topological sort |
Tree sort
Given an Array, derive a sequence of elements in which all duplicates are removed.
There are basically three approaches seen here:
Put the elements into a hash table which does not allow duplicates. The complexity is O(n) on average, and O(n2) worst case. This approach requires a hash function for your type (which is compatible with equality), either built-in to your language, or provided by the user.
Sort the elements and remove consecutive duplicate elements. The complexity of the best sorting algorithms is O(n log n). This approach requires that your type be "comparable", i.e., have an ordering. Putting the elements into a self-balancing binary search tree is a special case of sorting.
Go through the list, and for each element, check the rest of the list to see if it appears again, and discard it if it does. The complexity is O(n2). The up-shot is that this always works on any type (provided that you can test for equality).
|
#Groovy
|
Groovy
|
def list = [1, 2, 3, 'a', 'b', 'c', 2, 3, 4, 'b', 'c', 'd']
assert list.size() == 12
println " Original List: ${list}"
// Filtering the List (non-mutating)
def list2 = list.unique(false)
assert list2.size() == 8
assert list.size() == 12
println " Filtered List: ${list2}"
// Filtering the List (in place)
list.unique()
assert list.size() == 8
println " Original List, filtered: ${list}"
def list3 = [1, 2, 3, 'a', 'b', 'c', 2, 3, 4, 'b', 'c', 'd']
assert list3.size() == 12
// Converting to Set
def set = list as Set
assert set.size() == 8
println " Set: ${set}"
|
http://rosettacode.org/wiki/Recaman%27s_sequence
|
Recaman's sequence
|
The Recamán's sequence generates Natural numbers.
Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated.
If the conditions don't hold then a(n) = a(n-1) + n.
Task
Generate and show here the first 15 members of the sequence.
Find and show here, the first duplicated number in the sequence.
Optionally: Find and show here, how many terms of the sequence are needed until all the integers 0..1000, inclusive, are generated.
References
A005132, The On-Line Encyclopedia of Integer Sequences.
The Slightly Spooky Recamán Sequence, Numberphile video.
Recamán's sequence, on Wikipedia.
|
#Sidef
|
Sidef
|
func recamans_generator() {
var term = 0
var prev = 0
var seen = Hash()
{
var this = (prev - term)
if ((this <= 0) || seen{this}) {
this = (prev + term)
}
prev = this
seen{this} = true
term++
this
}
}
with (recamans_generator()) { |r|
say ("First 15 terms of the Recaman's sequence: ", 15.of { r.run }.join(', '))
}
with (recamans_generator()) {|r|
var seen = Hash()
Inf.times {|i|
var n = r.run
if (seen{n}) {
say "First duplicate term in the series is a(#{i}) = #{n}"
break
}
seen{n} = true
}
}
with (recamans_generator()) {|r|
var seen = Hash()
Inf.times {|i|
var n = r.run
if ((n <= 1000) && (seen{n} := true) && (seen.len == 1001)) {
say "Terms up to a(#{i}) are needed to generate 0 to 1000"
break
}
}
}
|
http://rosettacode.org/wiki/Reduced_row_echelon_form
|
Reduced row echelon form
|
Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this will probably be a two-dimensional array).
Built-in functions or this pseudocode (from Wikipedia) may be used:
function ToReducedRowEchelonForm(Matrix M) is
lead := 0
rowCount := the number of rows in M
columnCount := the number of columns in M
for 0 ≤ r < rowCount do
if columnCount ≤ lead then
stop
end if
i = r
while M[i, lead] = 0 do
i = i + 1
if rowCount = i then
i = r
lead = lead + 1
if columnCount = lead then
stop
end if
end if
end while
Swap rows i and r
If M[r, lead] is not 0 divide row r by M[r, lead]
for 0 ≤ i < rowCount do
if i ≠ r do
Subtract M[i, lead] multiplied by row r from row i
end if
end for
lead = lead + 1
end for
end function
For testing purposes, the RREF of this matrix:
1 2 -1 -4
2 3 -1 -11
-2 0 -3 22
is:
1 0 0 -8
0 1 0 1
0 0 1 -2
|
#Maxima
|
Maxima
|
rref(a):=block([p,q,k],[p,q]:matrix_size(a),a:echelon(a),
k:min(p,q),
for i thru min(p,q) do (if a[i,i]=0 then (k:i-1,return())),
for i:k thru 2 step -1 do (for j from i-1 thru 1 step -1 do a:rowop(a,j,i,a[j,i])),
a)$
a: matrix([12,-27,36,44,59],
[26,41,-54,24,23],
[33,70,59,15,-68],
[43,16,29,-52,-61],
[-43,20,71,88,11])$
rref(a);
matrix([1,0,0,0,1/2],[0,1,0,0,-1],[0,0,1,0,-1/2],[0,0,0,1,1],[0,0,0,0,0])
|
http://rosettacode.org/wiki/Real_constants_and_functions
|
Real constants and functions
|
Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
|
#jq
|
jq
|
1 | exp # i.e. e
1 | atan * 4 # i.e. π
sqrt
log # Naperian log
exp
length # absolute value if the argument is numeric
floor
ceil # requires jq >= 1.5
pow(x; y) # requires jq >= 1.5
|
http://rosettacode.org/wiki/Real_constants_and_functions
|
Real constants and functions
|
Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest integer less than or equal to this number--not the same as truncate or int)
ceiling (smallest integer not less than this number--not the same as round up)
power (xy )
Related task
Trigonometric Functions
|
#Jsish
|
Jsish
|
/* real constants and functions, in JSI */
var x, y;
;Math.E;
;Math.PI;
;x = 100.0;
;Math.sqrt(x);
;Math.log(x);
;x = 2.0;
;Math.exp(x);
;x = -x;
;Math.abs(x);
;x = 42.42;
;Math.floor(x);
;Math.ceil(x);
;x = 10.0;
;y = 5;
;Math.pow(x,y);
/*
=!EXPECTSTART!=
Math.E ==> 2.718281828459045
Math.PI ==> 3.141592653589793
x = 100.0 ==> 100
Math.sqrt(x) ==> 10
Math.log(x) ==> 4.605170185988092
x = 2.0 ==> 2
Math.exp(x) ==> 7.38905609893065
x = -x ==> -2
Math.abs(x) ==> 2
x = 42.42 ==> 42.42
Math.floor(x) ==> 42
Math.ceil(x) ==> 43
x = 10.0 ==> 10
y = 5 ==> 5
Math.pow(x,y) ==> 100000
=!EXPECTEND!=
*/
|
http://rosettacode.org/wiki/Remove_lines_from_a_file
|
Remove lines from a file
|
Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remove the first two lines from the file foobar.txt, the parameters should be: foobar.txt, 1, 2
Empty lines are considered and should still be counted, and if the specified line is empty, it should still be removed.
An appropriate message should appear if an attempt is made to remove lines beyond the end of the file.
|
#Run_BASIC
|
Run BASIC
|
fileName$ = "aFile.txt"
startLine = 100
lineCount = 10
open filename$ for input as #in
open filename$ ; "_tmp" for output as #out
while not(eof(#in))
lineNum = lineNum + 1
line input #in, a$
if lineNum < startLine or lineNum >= startLine + lineCount then print #out, a$
wend
close #in
close #out
|
http://rosettacode.org/wiki/Remove_lines_from_a_file
|
Remove lines from a file
|
Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remove the first two lines from the file foobar.txt, the parameters should be: foobar.txt, 1, 2
Empty lines are considered and should still be counted, and if the specified line is empty, it should still be removed.
An appropriate message should appear if an attempt is made to remove lines beyond the end of the file.
|
#Rust
|
Rust
|
extern crate rustc_serialize;
extern crate docopt;
use docopt::Docopt;
use std::io::{BufReader,BufRead};
use std::fs::File;
const USAGE: &'static str = "
Usage: rosetta <start> <count> <file>
";
#[derive(Debug, RustcDecodable)]
struct Args {
arg_start: usize,
arg_count: usize,
arg_file: String,
}
fn main() {
let args: Args = Docopt::new(USAGE)
.and_then(|d| d.decode())
.unwrap_or_else(|e| e.exit());
let file = BufReader::new(File::open(args.arg_file).unwrap());
for (i, line) in file.lines().enumerate() {
let cur = i + 1;
if cur < args.arg_start || cur >= (args.arg_start + args.arg_count) {
println!("{}", line.unwrap());
}
}
}
|
http://rosettacode.org/wiki/Read_entire_file
|
Read entire file
|
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
|
#LiveCode
|
LiveCode
|
put URL "file:///usr/share/dict/words" into tVar
put the number of lines of tVar
|
http://rosettacode.org/wiki/Read_entire_file
|
Read entire file
|
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case check File IO);
this is for those cases where having the entire file is actually what is wanted.
|
#Lua
|
Lua
|
--If the file opens with no problems, io.open will return a
--handle to the file with methods attached.
--If the file does not exist, io.open will return nil and
--an error message.
--assert will return the handle to the file if present, or
--it will throw an error with the message returned second
--by io.open.
local file = assert(io.open(filename))
--Without wrapping io.open in an assert, local file would be nil,
--which would cause an 'attempt to index a nil value' error when
--calling file:read.
--file:read takes the number of bytes to read, or a string for
--special cases, such as "*a" to read the entire file.
local contents = file:read'*a'
--If the file handle was local to the expression
--(ie. "assert(io.open(filename)):read'a'"),
--the file would remain open until its handle was
--garbage collected.
file:close()
|
http://rosettacode.org/wiki/Rep-string
|
Rep-string
|
Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For example, the string 10011001100 is a rep-string as the leftmost four characters of 1001 are repeated three times and truncated on the right to give the original string.
Note that the requirement for having the repeat occur two or more times means that the repeating unit is never longer than half the length of the input string.
Task
Write a function/subroutine/method/... that takes a string and returns an indication of if it is a rep-string and the repeated string. (Either the string that is repeated, or the number of repeated characters would suffice).
There may be multiple sub-strings that make a string a rep-string - in that case an indication of all, or the longest, or the shortest would suffice.
Use the function to indicate the repeating substring if any, in the following:
1001110011
1110111011
0010010010
1010101010
1111111111
0100101101
0100100
101
11
00
1
Show your output on this page.
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
|
#Snobol4
|
Snobol4
|
* Rep-string
strings = "1001110011 1110111011 0010010010 1010101010 1111111111 0100101101 0100100 101 11 00 1 "
pat1 = (len(1) $ fc breakx(*fc)) $ x *x (arbno(*x) (rpos(0) | rem $ y *?(x ? y)))
getstring
strings ? (break(" ") . rs len(1)) = :f(end)
rs ? pat1 :s(yes)
output = rs " is not a rep-string -> n/a" :(getstring)
yes
output = rs " has shortest rep-string value of -> " x
:(getstring)
end
|
http://rosettacode.org/wiki/Rep-string
|
Rep-string
|
Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For example, the string 10011001100 is a rep-string as the leftmost four characters of 1001 are repeated three times and truncated on the right to give the original string.
Note that the requirement for having the repeat occur two or more times means that the repeating unit is never longer than half the length of the input string.
Task
Write a function/subroutine/method/... that takes a string and returns an indication of if it is a rep-string and the repeated string. (Either the string that is repeated, or the number of repeated characters would suffice).
There may be multiple sub-strings that make a string a rep-string - in that case an indication of all, or the longest, or the shortest would suffice.
Use the function to indicate the repeating substring if any, in the following:
1001110011
1110111011
0010010010
1010101010
1111111111
0100101101
0100100
101
11
00
1
Show your output on this page.
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
|
#Swift
|
Swift
|
import Foundation
func repString(_ input: String) -> [String] {
return (1..<(1 + input.count / 2)).compactMap({x -> String? in
let i = input.index(input.startIndex, offsetBy: x)
return input.hasPrefix(input[i...]) ? String(input.prefix(x)) : nil
})
}
let testCases = """
1001110011
1110111011
0010010010
1010101010
1111111111
0100101101
0100100
101
11
00
1
""".components(separatedBy: "\n")
for testCase in testCases {
print("\(testCase) has reps: \(repString(testCase))")
}
|
http://rosettacode.org/wiki/Regular_expressions
|
Regular expressions
|
Task
match a string against a regular expression
substitute part of a string using a regular expression
|
#REXX
|
REXX
|
/*REXX program demonstrates testing (modeled after Perl example).*/
$string="I am a string"
say 'The string is:' $string
x="string" ; if right($string,length(x))=x then say 'It ends with:' x
y="You" ; if left($string,length(y))\=y then say 'It does not start with:' y
z="ring" ; if pos(z,$string)\==0 then say 'It contains the string:' z
z="ring" ; if wordpos(z,$string)==0 then say 'It does not contain the word:' z
/*stick a fork in it, we're done.*/
|
http://rosettacode.org/wiki/Reverse_a_string
|
Reverse a string
|
Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
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
|
function ReverseString(const InString: string): string;
var
i: integer;
begin
for i := Length(InString) downto 1 do
Result := Result + InString[i];
end;
|
http://rosettacode.org/wiki/Rename_a_file
|
Rename a file
|
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type systems, only the user root would have
sufficient permissions in the filesystem root.)
|
#Smalltalk
|
Smalltalk
|
File rename: 'input.txt' to: 'output.txt'.
File rename: 'docs' to: 'mydocs'.
"as for other example, this works on systems
where the root is / ..."
File rename: '/input.txt' to: '/output.txt'.
File rename: '/docs' to: '/mydocs'
|
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