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http://rosettacode.org/wiki/Deal_cards_for_FreeCell
Deal cards for FreeCell
Free Cell is the solitaire card game that Paul Alfille introduced to the PLATO system in 1978. Jim Horne, at Microsoft, changed the name to FreeCell and reimplemented the game for DOS, then Windows. This version introduced 32000 numbered deals. (The FreeCell FAQ tells this history.) As the game became popular, Jim Horne disclosed the algorithm, and other implementations of FreeCell began to reproduce the Microsoft deals. These deals are numbered from 1 to 32000. Newer versions from Microsoft have 1 million deals, numbered from 1 to 1000000; some implementations allow numbers outside that range. The algorithm uses this linear congruential generator from Microsoft C: s t a t e n + 1 ≡ 214013 × s t a t e n + 2531011 ( mod 2 31 ) {\displaystyle state_{n+1}\equiv 214013\times state_{n}+2531011{\pmod {2^{31}}}} r a n d n = s t a t e n ÷ 2 16 {\displaystyle rand_{n}=state_{n}\div 2^{16}} r a n d n {\displaystyle rand_{n}} is in range 0 to 32767. Rosetta Code has another task, linear congruential generator, with code for this RNG in several languages. The algorithm follows: Seed the RNG with the number of the deal. Create an array of 52 cards: Ace of Clubs, Ace of Diamonds, Ace of Hearts, Ace of Spades, 2 of Clubs, 2 of Diamonds, and so on through the ranks: Ace, 2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen, King. The array indexes are 0 to 51, with Ace of Clubs at 0, and King of Spades at 51. Until the array is empty: Choose a random card at index ≡ next random number (mod array length). Swap this random card with the last card of the array. Remove this random card from the array. (Array length goes down by 1.) Deal this random card. Deal all 52 cards, face up, across 8 columns. The first 8 cards go in 8 columns, the next 8 cards go on the first 8 cards, and so on. Order to deal cards Game #1 Game #617 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 JD 2D 9H JC 5D 7H 7C 5H KD KC 9S 5S AD QC KH 3H 2S KS 9D QD JS AS AH 3C 4C 5C TS QH 4H AC 4D 7S 3S TD 4S TH 8H 2C JH 7D 6D 8S 8D QS 6C 3D 8C TC 6S 9C 2H 6H 7D AD 5C 3S 5S 8C 2D AH TD 7S QD AC 6D 8H AS KH TH QC 3H 9D 6S 8D 3D TC KD 5H 9S 3C 8S 7H 4D JS 4C QS 9C 9H 7C 6H 2C 2S 4S TS 2H 5D JC 6C JH QH JD KS KC 4H Deals can also be checked against FreeCell solutions to 1000000 games. (Summon a video solution, and it displays the initial deal.) Write a program to take a deal number and deal cards in the same order as this algorithm. The program may display the cards with ASCII, with Unicode, by drawing graphics, or any other way. Related tasks: Playing cards Card shuffles War Card_Game Poker hand_analyser Go Fish
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
next[last_] := Mod[214013 last + 2531011, 2^31]; deal[n_] := Module[{last = n, idx, deck = StringJoin /@ Tuples[{{"A", "2", "3", "4", "5", "6", "7", "8", "9", "T", "J", "Q", "K"}, {"C", "D", "H", "S"}}], res = {}}, While[deck != {}, last = next[last]; idx = Mod[BitShiftRight[last, 16], Length[deck]] + 1; deck = ReplacePart[deck, {idx -> deck[[-1]], -1 -> deck[[idx]]}]; AppendTo[res, deck[[-1]]]; deck = deck[[;; -2]]]; res]; format[deal_] := Grid[Partition[deal, 8, 8, {1, 4}, Null]]; Print[format[deal[1]]]; Print[format[deal[617]]];
http://rosettacode.org/wiki/Deal_cards_for_FreeCell
Deal cards for FreeCell
Free Cell is the solitaire card game that Paul Alfille introduced to the PLATO system in 1978. Jim Horne, at Microsoft, changed the name to FreeCell and reimplemented the game for DOS, then Windows. This version introduced 32000 numbered deals. (The FreeCell FAQ tells this history.) As the game became popular, Jim Horne disclosed the algorithm, and other implementations of FreeCell began to reproduce the Microsoft deals. These deals are numbered from 1 to 32000. Newer versions from Microsoft have 1 million deals, numbered from 1 to 1000000; some implementations allow numbers outside that range. The algorithm uses this linear congruential generator from Microsoft C: s t a t e n + 1 ≡ 214013 × s t a t e n + 2531011 ( mod 2 31 ) {\displaystyle state_{n+1}\equiv 214013\times state_{n}+2531011{\pmod {2^{31}}}} r a n d n = s t a t e n ÷ 2 16 {\displaystyle rand_{n}=state_{n}\div 2^{16}} r a n d n {\displaystyle rand_{n}} is in range 0 to 32767. Rosetta Code has another task, linear congruential generator, with code for this RNG in several languages. The algorithm follows: Seed the RNG with the number of the deal. Create an array of 52 cards: Ace of Clubs, Ace of Diamonds, Ace of Hearts, Ace of Spades, 2 of Clubs, 2 of Diamonds, and so on through the ranks: Ace, 2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen, King. The array indexes are 0 to 51, with Ace of Clubs at 0, and King of Spades at 51. Until the array is empty: Choose a random card at index ≡ next random number (mod array length). Swap this random card with the last card of the array. Remove this random card from the array. (Array length goes down by 1.) Deal this random card. Deal all 52 cards, face up, across 8 columns. The first 8 cards go in 8 columns, the next 8 cards go on the first 8 cards, and so on. Order to deal cards Game #1 Game #617 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 JD 2D 9H JC 5D 7H 7C 5H KD KC 9S 5S AD QC KH 3H 2S KS 9D QD JS AS AH 3C 4C 5C TS QH 4H AC 4D 7S 3S TD 4S TH 8H 2C JH 7D 6D 8S 8D QS 6C 3D 8C TC 6S 9C 2H 6H 7D AD 5C 3S 5S 8C 2D AH TD 7S QD AC 6D 8H AS KH TH QC 3H 9D 6S 8D 3D TC KD 5H 9S 3C 8S 7H 4D JS 4C QS 9C 9H 7C 6H 2C 2S 4S TS 2H 5D JC 6C JH QH JD KS KC 4H Deals can also be checked against FreeCell solutions to 1000000 games. (Summon a video solution, and it displays the initial deal.) Write a program to take a deal number and deal cards in the same order as this algorithm. The program may display the cards with ASCII, with Unicode, by drawing graphics, or any other way. Related tasks: Playing cards Card shuffles War Card_Game Poker hand_analyser Go Fish
#Nim
Nim
import sequtils, strutils, os   proc randomGenerator(seed: int): iterator: int = var state = seed return iterator: int = while true: state = (state * 214013 + 2531011) and int32.high yield state shr 16   proc deal(seed: int): seq[int] = const nc = 52 result = toSeq countdown(nc - 1, 0) var rnd = randomGenerator seed for i in 0 ..< nc: let r = rnd() let j = (nc - 1) - r mod (nc - i) swap result[i], result[j]   proc show(cards: seq[int]) = var l = newSeq[string]() for c in cards: l.add "A23456789TJQK"[c div 4] & "CDHS"[c mod 4] for i in countup(0, cards.high, 8): echo " ", l[i..min(i+7, l.high)].join(" ")   let seed = if paramCount() == 1: paramStr(1).parseInt else: 11982 echo "Hand ", seed let deck = deal seed show deck
http://rosettacode.org/wiki/Define_a_primitive_data_type
Define a primitive data type
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
#Racket
Racket
  #lang racket   (provide (contract-out [x 1-to-10/c]))   (define 1-to-10/c (between/c 1 10))   (define x 5)  
http://rosettacode.org/wiki/Define_a_primitive_data_type
Define a primitive data type
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
#Raku
Raku
subset OneToTen of Int where 1..10;   my OneToTen $n = 5; $n += 6;
http://rosettacode.org/wiki/Day_of_the_week
Day of the week
A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January). Task In what years between 2008 and 2121 will the 25th of December be a Sunday? Using any standard date handling libraries of your programming language; compare the dates calculated with the output of other languages to discover any anomalies in the handling of dates which may be due to, for example, overflow in types used to represent dates/times similar to   y2k   type problems.
#BCPL
BCPL
get "libhdr"   let weekday(y, m, d) = m<3 -> wd((y-1)/100, (y-1) rem 100, m + 10, d), wd(y/100, y rem 100, m - 2, d) and wd(c, y, m, d) = ((26*m-2)/10 + d + y + y/4 + c/4 - 2 * c + 777) rem 7   let start() be for year = 2008 to 2121 if weekday(year, 12, 25) = 0 do writef("%N*N", year)
http://rosettacode.org/wiki/CUSIP
CUSIP
This page uses content from Wikipedia. The original article was at CUSIP. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) A   CUSIP   is a nine-character alphanumeric code that identifies a North American financial security for the purposes of facilitating clearing and settlement of trades. The CUSIP was adopted as an American National Standard under Accredited Standards X9.6. Task Ensure the last digit   (i.e., the   check digit)   of the CUSIP code (the 1st column) is correct, against the following:   037833100       Apple Incorporated   17275R102       Cisco Systems   38259P508       Google Incorporated   594918104       Microsoft Corporation   68389X106       Oracle Corporation   (incorrect)   68389X105       Oracle Corporation Example pseudo-code below. algorithm Cusip-Check-Digit(cusip) is Input: an 8-character CUSIP   sum := 0 for 1 ≤ i ≤ 8 do c := the ith character of cusip if c is a digit then v := numeric value of the digit c else if c is a letter then p := ordinal position of c in the alphabet (A=1, B=2...) v := p + 9 else if c = "*" then v := 36 else if c = "@" then v := 37 else if' c = "#" then v := 38 end if if i is even then v := v × 2 end if   sum := sum + int ( v div 10 ) + v mod 10 repeat   return (10 - (sum mod 10)) mod 10 end function See related tasks SEDOL ISIN
#360_Assembly
360 Assembly
* CUSIP 07/06/2018 CUSIP CSECT USING CUSIP,R13 base register B 72(R15) skip savearea DC 17F'0' savearea SAVE (14,12) save previous context ST R13,4(R15) link backward ST R15,8(R13) link forward LR R13,R15 set addressability LA R6,1 i=1 DO WHILE=(C,R6,LE,=F'6') do i=1 to 6 LR R1,R6 i MH R1,=H'9' *9 LA R4,T-9(R1) @t(i) MVC X,0(R4) x=t(i) SR R10,R10 w=0 LA R7,1 j=1 DO WHILE=(C,R7,LE,=F'8') do j=1 to 8 LA R14,X-1 x AR R14,R7 j MVC Y(1),0(R14) y=substr(x,j,1) LA R9,L'XX z=length(xx) LA R8,1 k=1 DO WHILE=(C,R8,LE,=A(L'XX)) do k=1 to length(xx) LA R4,XX-1 xx AR R4,R8 k MVC C(1),0(R4) c=substr(xx,k,1) IF CLC,Y(1),EQ,C THEN if y=c then LR R9,R8 k BCTR R9,0 z=k-1 ENDIF , endif LA R8,1(R8) k++ ENDDO , enddo k LR R4,R7 j LA R1,2 2 SRDA R4,32 ~ DR R4,R1 j/2=0 IF LTR,R4,Z,R4 THEN if j//2=0 then AR R9,R9 z=z+z ENDIF , endif LR R4,R9 z LA R1,10 10 SRDA R4,32 ~ DR R4,R1 r4=z//10 ; r5=z/10 AR R10,R5 w+z/10 AR R10,R4 w=w+z/10+z//10 LA R7,1(R7) j++ ENDDO , enddo j LR R4,R10 w LA R1,10 10 SRDA R4,32 ~ DR R4,R1 w/10 LA R2,10 10 SR R2,R4 10-w//10 SRDA R2,32 ~ DR R2,R1 /10 STC R2,U u=(10-w//10)//10 OI U,X'F0' bin to char IF CLC,U,EQ,X+8 THEN if u=substr(x,9,1) then MVC OK,=CL3' ' ok=' ' ELSE , else MVC OK,=C'n''t' ok='n''t' ENDIF , endif MVC PG+6(9),X output x MVC PG+18(3),OK output ok XPRNT PG,L'PG print LA R6,1(R6) i++ ENDDO , enddo i L R13,4(0,R13) restore previous savearea pointer RETURN (14,12),RC=0 restore registers from calling sav XX DC CL39'0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*@#' U DS CL1 Y DS CL1 C DS CL1 T DC CL9'037833100',CL9'17275R102',CL9'38259P508' DC CL9'594918104',CL9'68389X106',CL9'68389X105' X DS CL9 OK DS CL3 PG DC CL80'CUSIP ......... is... valid' YREGS END CUSIP
http://rosettacode.org/wiki/CUSIP
CUSIP
This page uses content from Wikipedia. The original article was at CUSIP. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) A   CUSIP   is a nine-character alphanumeric code that identifies a North American financial security for the purposes of facilitating clearing and settlement of trades. The CUSIP was adopted as an American National Standard under Accredited Standards X9.6. Task Ensure the last digit   (i.e., the   check digit)   of the CUSIP code (the 1st column) is correct, against the following:   037833100       Apple Incorporated   17275R102       Cisco Systems   38259P508       Google Incorporated   594918104       Microsoft Corporation   68389X106       Oracle Corporation   (incorrect)   68389X105       Oracle Corporation Example pseudo-code below. algorithm Cusip-Check-Digit(cusip) is Input: an 8-character CUSIP   sum := 0 for 1 ≤ i ≤ 8 do c := the ith character of cusip if c is a digit then v := numeric value of the digit c else if c is a letter then p := ordinal position of c in the alphabet (A=1, B=2...) v := p + 9 else if c = "*" then v := 36 else if c = "@" then v := 37 else if' c = "#" then v := 38 end if if i is even then v := v × 2 end if   sum := sum + int ( v div 10 ) + v mod 10 repeat   return (10 - (sum mod 10)) mod 10 end function See related tasks SEDOL ISIN
#Action.21
Action!
INCLUDE "D2:CHARTEST.ACT" ;from the Action! Tool Kit   BYTE FUNC Verify(CHAR ARRAY code) BYTE i,c,v CARD sum   IF code(0)#9 THEN RETURN (0) ELSEIF IsDigit(code(1))=0 THEN RETURN (0) FI   sum=0 FOR i=2 TO code(0) DO c=code(i) IF IsDigit(c) THEN v=c-'0 ELSEIF IsAlpha(c) THEN v=ToUpper(c)-'A+10 ELSEIF c='* THEN v=36 ELSEIF c='@ THEN v=37 ELSEIF c='# THEN v=38 ELSE RETURN (0) FI   IF (i&1)=0 THEN v==*2 FI   sum==+v/10+v MOD 10 OD   v=(10-(sum MOD 10)) MOD 10 IF v#code(1)-'0 THEN RETURN (0) FI RETURN (1)   PROC Test(CHAR ARRAY code) Print(code) IF Verify(code) THEN PrintE(" is valid") ELSE PrintE(" is invalid") FI RETURN   PROC Main() Put(125) PutE() ;clear the screen Test("037833100") Test("17275R102") Test("38259P508") Test("594918104") Test("68389X106") Test("68389X105") RETURN
http://rosettacode.org/wiki/Date_format
Date format
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the   current date   in the formats of:   2007-11-23     and   Friday, November 23, 2007
#ABAP
ABAP
  report zdate. data: lv_month type string, lv_weekday type string, lv_date type string, lv_day type c.   call function 'DATE_COMPUTE_DAY' exporting date = sy-datum importing day = lv_day. select single ltx from t247 into lv_month where spras = sy-langu and mnr = sy-datum+4(2).   select single langt from t246 into lv_weekday where sprsl = sy-langu and wotnr = lv_day.   concatenate lv_weekday ', ' lv_month ' ' sy-datum+6(2) ', ' sy-datum(4) into lv_date respecting blanks. write lv_date. concatenate sy-datum(4) '-' sy-datum+4(2) '-' sy-datum+6(2) into lv_date. write / lv_date.  
http://rosettacode.org/wiki/Damm_algorithm
Damm algorithm
The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors. The algorithm is named after H. Michael Damm. Task Verify the checksum, stored as last digit of an input.
#ALGOL_68
ALGOL 68
BEGIN # returns TRUE if the check digit of s is correct according to the Damm algorithm, # # FALSE otherwise # PROC has valid damm check digit = ( STRING s )BOOL: BEGIN # operation table - as per wikipedia example # [,]INT operation table = ( [,]INT( ( 0, 3, 1, 7, 5, 9, 8, 6, 4, 2 ) , ( 7, 0, 9, 2, 1, 5, 4, 8, 6, 3 ) , ( 4, 2, 0, 6, 8, 7, 1, 3, 5, 9 ) , ( 1, 7, 5, 0, 9, 8, 3, 4, 2, 6 ) , ( 6, 1, 2, 3, 0, 4, 5, 9, 7, 8 ) , ( 3, 6, 7, 4, 2, 0, 9, 5, 8, 1 ) , ( 5, 8, 6, 9, 7, 2, 0, 1, 3, 4 ) , ( 8, 9, 4, 5, 3, 6, 2, 0, 1, 7 ) , ( 9, 4, 3, 8, 6, 1, 7, 2, 0, 5 ) , ( 2, 5, 8, 1, 4, 3, 6, 7, 9, 0 ) ) ) [ AT 0, AT 0 ] ; INT interim digit := 0; FOR s pos FROM LWB s TO UPB s DO INT next digit = ABS s[ s pos ] - ABS "0"; IF next digit < 0 OR next digit > 9 THEN # invalid digit # print( ( "Invalid damm digit: ", s[ s pos ], newline ) ); stop ELSE # have a valid digit # interim digit := operation table[ interim digit, next digit ] FI OD; interim digit = 0 END # has valid damm check digit # ;   # test the damm algorithm # PROC test damm algorithm = ( STRING s, BOOL expected )VOID: BEGIN BOOL valid = has valid damm check digit( s ); print( ( "check digit of ", s, " is " , IF valid THEN "valid" ELSE "invalid" FI , IF valid = expected THEN "" ELSE " *** NOT AS EXPECTED" FI , newline ) ) END # test damm algorithm # ; # test cases - as per other language samples # test damm algorithm( "5724", TRUE ); test damm algorithm( "5727", FALSE ); test damm algorithm( "112946", TRUE ) END
http://rosettacode.org/wiki/Curzon_numbers
Curzon numbers
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1. Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1. Base here does not imply the radix of the counting system; rather the integer the equation is based on. All calculations should be done in base 10. Generalized Curzon numbers only exist for even base integers. Task Find and show the first 50 Generalized Curzon numbers for even base integers from 2 through 10. Stretch Find and show the one thousandth. See also Numbers Aplenty - Curzon numbers OEIS:A224486 - Numbers k such that 2*k+1 divides 2^k+1 (Curzon numbers) and even though it is not specifically mentioned that they are Curzon numbers: OEIS:A230076 - (A007521(n)-1)/4 (Generalized Curzon numbers with a base 4)
#Go
Go
package main   import ( "fmt" "math/big" )   func main() { zero := big.NewInt(0) one := big.NewInt(1) for k := int64(2); k <= 10; k += 2 { bk := big.NewInt(k) fmt.Println("The first 50 Curzon numbers using a base of", k, ":") count := 0 n := int64(1) pow := big.NewInt(k) z := new(big.Int) var curzon50 []int64 for { z.Add(pow, one) d := k*n + 1 bd := big.NewInt(d) if z.Rem(z, bd).Cmp(zero) == 0 { if count < 50 { curzon50 = append(curzon50, n) } count++ if count == 50 { for i := 0; i < len(curzon50); i++ { fmt.Printf("%4d ", curzon50[i]) if (i+1)%10 == 0 { fmt.Println() } } fmt.Print("\nOne thousandth: ") } if count == 1000 { fmt.Println(n) break } } n++ pow.Mul(pow, bk) } fmt.Println() } }
http://rosettacode.org/wiki/Curzon_numbers
Curzon numbers
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1. Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1. Base here does not imply the radix of the counting system; rather the integer the equation is based on. All calculations should be done in base 10. Generalized Curzon numbers only exist for even base integers. Task Find and show the first 50 Generalized Curzon numbers for even base integers from 2 through 10. Stretch Find and show the one thousandth. See also Numbers Aplenty - Curzon numbers OEIS:A224486 - Numbers k such that 2*k+1 divides 2^k+1 (Curzon numbers) and even though it is not specifically mentioned that they are Curzon numbers: OEIS:A230076 - (A007521(n)-1)/4 (Generalized Curzon numbers with a base 4)
#jq
jq
# To take advantage of gojq's arbitrary-precision integer arithmetic: def power($b): . as $in | reduce range(0;$b) as $i (1; . * $in);   def lpad($len): tostring | ($len - length) as $l | (" " * $l)[:$l] + .;   # gojq does not currently define _nwise def _nwise($n): def n: if length <= $n then . else .[0:$n] , (.[$n:] | n) end; n;   def printRows($m): _nwise($m) | map(lpad(5)) | join("");
http://rosettacode.org/wiki/Cut_a_rectangle
Cut a rectangle
A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such paths for 2 × 2 and 4 × 3 rectangles are shown below. Write a program that calculates the number of different ways to cut an m × n rectangle. Optionally, show each of the cuts. Possibly related task: Maze generation for depth-first search.
#Delphi
Delphi
  program Cut_a_rectangle;   {$APPTYPE CONSOLE}   uses System.SysUtils;   var grid: array of byte; w, h, len: Integer; cnt: UInt64; next: array of Integer; dir: array of array of Integer = [[0, -1], [-1, 0], [0, 1], [1, 0]];   procedure walk(y, x: Integer); var i, t: Integer; begin if (y = 0) or (y = h) or (x = 0) or (x = w) then begin inc(cnt); Exit; end; t := y * (w + 1) + x; inc(grid[t]); inc(grid[len - t]);   for i := 0 to 3 do if grid[t + next[i]] = 0 then walk(y + dir[i][0], x + dir[i][1]); dec(grid[t]); dec(grid[len - t]); end;   function solve(hh, ww: Integer; recur: Boolean): UInt64; var t, cx, cy, x, i: Integer; begin h := hh; w := ww;   if Odd(h) then begin t := w; w := h; h := t; end;   if Odd(h) then Exit(0);   if w = 1 then Exit(1);   if w = 2 then Exit(h);   if h = 2 then Exit(w);   cy := h div 2; cx := w div 2; len := (h + 1) * (w + 1);   setlength(grid, len);   for i := 0 to High(grid) do grid[i] := 0;   dec(len);   next := [-1, -w - 1, 1, w + 1];   if recur then cnt := 0;   for x := cx + 1 to w - 1 do begin t := cy * (w + 1) + x; grid[t] := 1; grid[len - t] := 1; walk(cy - 1, x); end; Inc(cnt);   if h = w then inc(cnt, 2) else if not odd(w) and recur then solve(w, h, False); Result := cnt; end;   var y, x: Integer;   begin for y := 1 to 10 do for x := 1 to y do if not Odd(x) or not Odd(y) then writeln(format('%d x %d:  %d', [y, x, solve(y, x, True)])); Readln; end.
http://rosettacode.org/wiki/Cyclops_numbers
Cyclops numbers
A cyclops number is a number with an odd number of digits that has a zero in the center, but nowhere else. They are named so in tribute to the one eyed giants Cyclops from Greek mythology. Cyclops numbers can be found in any base. This task strictly is looking for cyclops numbers in base 10. There are many different classifications of cyclops numbers with minor differences in characteristics. In an effort to head off a whole series of tasks with tiny variations, we will cover several variants here. Task Find and display here on this page the first 50 cyclops numbers in base 10 (all of the sub tasks are restricted to base 10). Find and display here on this page the first 50 prime cyclops numbers. (cyclops numbers that are prime.) Find and display here on this page the first 50 blind prime cyclops numbers. (prime cyclops numbers that remain prime when "blinded"; the zero is removed from the center.) Find and display here on this page the first 50 palindromic prime cyclops numbers. (prime cyclops numbers that are palindromes.) Stretch Find and display the first cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first blind prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first palindromic prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. (Note: there are no cyclops numbers between ten million and one hundred million, they need to have an odd number of digits) See also OEIS A134808 - Cyclops numbers OEIS A134809 - Cyclops primes OEIS A329737 - Cyclops primes that remain prime after being "blinded" OEIS A136098 - Prime palindromic cyclops numbers
#Perl
Perl
use strict; use warnings; use feature 'say'; use ntheory 'is_prime'; use List::AllUtils 'firstidx';   sub comma { reverse ((reverse shift) =~ s/(.{3})/$1,/gr) =~ s/^,//r }   my @cyclops = 0; for my $exp (0..3) { my @oom = grep { ! /0/ } 10**$exp .. 10**($exp+1)-1; for my $l (@oom) { for my $r (@oom) { push @cyclops, $l . '0' . $r; } } }   my @prime_cyclops = grep { is_prime $_ } @cyclops; my @prime_blind = grep { is_prime $_ =~ s/0//r } @prime_cyclops; my @prime_palindr = grep { $_ eq reverse $_ } @prime_cyclops;   my $upto = 50; my $over = 10_000_000;   for ( ['', @cyclops], ['prime', @prime_cyclops], ['blind prime', @prime_blind], ['palindromic prime', @prime_palindr]) { my($text,@values) = @$_; my $i = firstidx { $_ > $over } @values; say "First $upto $text cyclops numbers:\n" . (sprintf "@{['%8d' x $upto]}", @values[0..$upto-1]) =~ s/(.{80})/$1\n/gr; printf "First $text number > %s: %s at (zero based) index: %s\n\n", map { comma($_) } $over, $values[$i], $i; }
http://rosettacode.org/wiki/Date_manipulation
Date manipulation
Task Given the date string "March 7 2009 7:30pm EST", output the time 12 hours later in any human-readable format. As extra credit, display the resulting time in a time zone different from your own.
#BBC_BASIC
BBC BASIC
INSTALL @lib$+"DATELIB"   date$ = "March 7 2009 7:30pm EST"   mjd% = FN_readdate(date$, "mdy", 0) colon% = INSTR(date$, ":") hours% = VAL(MID$(date$, colon%-2)) IF INSTR(date$, "am") IF hours%=12 hours% -= 12 IF INSTR(date$, "pm") IF hours%<>12 hours% += 12 mins% = VAL(MID$(date$, colon%+1))   now% = mjd% * 1440 + hours% * 60 + mins% new% = now% + 12 * 60 : REM 12 hours later   PRINT FNformat(new%, "EST") PRINT FNformat(new% + 5 * 60, "GMT") PRINT FNformat(new% - 3 * 60, "PST") END   DEF FNformat(datetime%, zone$) LOCAL mjd%, hours%, mins%, ampm$ mjd% = datetime% DIV 1440 hours% = (datetime% DIV 60) MOD 24 mins% = datetime% MOD 60   IF hours% < 12 THEN ampm$ = "am" ELSE ampm$ = "pm" IF hours% = 0 hours% += 12 IF hours% > 12 hours% -= 12   = FN_date$(mjd%, "MMMM d yyyy") + " " + STR$(hours%) + \ \ ":" + RIGHT$("0"+STR$(mins%), 2) + ampm$ + " " + zone$ ENDPROC  
http://rosettacode.org/wiki/Date_manipulation
Date manipulation
Task Given the date string "March 7 2009 7:30pm EST", output the time 12 hours later in any human-readable format. As extra credit, display the resulting time in a time zone different from your own.
#C
C
#include <stdio.h> #include <stdlib.h> #include <time.h>   int main() { struct tm ts; time_t t; const char *d = "March 7 2009 7:30pm EST";   strptime(d, "%B %d %Y %I:%M%p %Z", &ts); /* ts.tm_hour += 12; instead of t += 12*60*60 works too. */ t = mktime(&ts); t += 12*60*60; printf("%s", ctime(&t));   return EXIT_SUCCESS; }
http://rosettacode.org/wiki/Deal_cards_for_FreeCell
Deal cards for FreeCell
Free Cell is the solitaire card game that Paul Alfille introduced to the PLATO system in 1978. Jim Horne, at Microsoft, changed the name to FreeCell and reimplemented the game for DOS, then Windows. This version introduced 32000 numbered deals. (The FreeCell FAQ tells this history.) As the game became popular, Jim Horne disclosed the algorithm, and other implementations of FreeCell began to reproduce the Microsoft deals. These deals are numbered from 1 to 32000. Newer versions from Microsoft have 1 million deals, numbered from 1 to 1000000; some implementations allow numbers outside that range. The algorithm uses this linear congruential generator from Microsoft C: s t a t e n + 1 ≡ 214013 × s t a t e n + 2531011 ( mod 2 31 ) {\displaystyle state_{n+1}\equiv 214013\times state_{n}+2531011{\pmod {2^{31}}}} r a n d n = s t a t e n ÷ 2 16 {\displaystyle rand_{n}=state_{n}\div 2^{16}} r a n d n {\displaystyle rand_{n}} is in range 0 to 32767. Rosetta Code has another task, linear congruential generator, with code for this RNG in several languages. The algorithm follows: Seed the RNG with the number of the deal. Create an array of 52 cards: Ace of Clubs, Ace of Diamonds, Ace of Hearts, Ace of Spades, 2 of Clubs, 2 of Diamonds, and so on through the ranks: Ace, 2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen, King. The array indexes are 0 to 51, with Ace of Clubs at 0, and King of Spades at 51. Until the array is empty: Choose a random card at index ≡ next random number (mod array length). Swap this random card with the last card of the array. Remove this random card from the array. (Array length goes down by 1.) Deal this random card. Deal all 52 cards, face up, across 8 columns. The first 8 cards go in 8 columns, the next 8 cards go on the first 8 cards, and so on. Order to deal cards Game #1 Game #617 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 JD 2D 9H JC 5D 7H 7C 5H KD KC 9S 5S AD QC KH 3H 2S KS 9D QD JS AS AH 3C 4C 5C TS QH 4H AC 4D 7S 3S TD 4S TH 8H 2C JH 7D 6D 8S 8D QS 6C 3D 8C TC 6S 9C 2H 6H 7D AD 5C 3S 5S 8C 2D AH TD 7S QD AC 6D 8H AS KH TH QC 3H 9D 6S 8D 3D TC KD 5H 9S 3C 8S 7H 4D JS 4C QS 9C 9H 7C 6H 2C 2S 4S TS 2H 5D JC 6C JH QH JD KS KC 4H Deals can also be checked against FreeCell solutions to 1000000 games. (Summon a video solution, and it displays the initial deal.) Write a program to take a deal number and deal cards in the same order as this algorithm. The program may display the cards with ASCII, with Unicode, by drawing graphics, or any other way. Related tasks: Playing cards Card shuffles War Card_Game Poker hand_analyser Go Fish
#Objeck
Objeck
class FreeCell { function : Main(args : String[]) ~ Nil { Deal(1)->PrintLine(); Deal(617)->PrintLine(); }   function : Deal(seed : Int) ~ String { deck := Deck->New(seed)->ToString(); return "Game #{$seed}:\n{$deck}\n"; } }   class Deck { @cards : Card[];   New(seed : Int) { r := Random->New(seed);   @cards := Card->New[52]; for(i := 0; i < 52; i+= 1;) { @cards[i] := Card->New(51 - i); };   for(i := 0; i < 51; i += 1;) { j := 51 - r->Next() % (52 - i); tmp := @cards[i]; @cards[i] := @cards[j]; @cards[j] := tmp; }; }   method : public : ToString() ~ String { buffer := "";   each(i : @cards) { buffer += @cards[i]->ToString(); buffer += (i % 8 = 7 ? "\n" : " "); };   return buffer; }     }   class Random { @seed : Int;   New(seed : Int) { @seed := seed; }   method : public : Next() ~ Int { @seed := (@seed * 214013 + 2531011) and Int->MaxSize(); return @seed >> 16; } }   class Card { @value : Int; @suit : Int;   New(value : Int) { @value := value / 4; @suit := value % 4; }   method : public : ToString() ~ String { suits := "♣♦♥♠"; values := "A23456789TJQK"; value := values->Get(@value); suit := suits->Get(@suit); return "{$value}{$suit}"; } }
http://rosettacode.org/wiki/Define_a_primitive_data_type
Define a primitive data type
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
#Retro
Retro
{{ variable update ---reveal---  : .limited @update &! &@ if update off ;  : to dup 1 10 within [ update on ] [ drop "Out of bounds\n" puts ] if ;  : limited: create 1 , &.limited reclass ; }}
http://rosettacode.org/wiki/Define_a_primitive_data_type
Define a primitive data type
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
#Ruby
Ruby
Some object-oriented languages won't let you subclass the "basic" data types like integers. Other languages implement those data types as classes, so you can subclass them, no questions asked. Ruby implements numbers as classes (Integer, with its concrete subclasses Fixnum and Bignum), and you can subclass those classes. If you try, though, you'll quickly discover that your subclasses are useless: they don't have constructors. Ruby jealously guards the creation of new Integer objects. This way it ensures that, for instance, there can be only one Fixnum instance for a given number The easiest way to delegate all methods is to create a class that's nearly empty and define a method_missing method.
http://rosettacode.org/wiki/Day_of_the_week
Day of the week
A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January). Task In what years between 2008 and 2121 will the 25th of December be a Sunday? Using any standard date handling libraries of your programming language; compare the dates calculated with the output of other languages to discover any anomalies in the handling of dates which may be due to, for example, overflow in types used to represent dates/times similar to   y2k   type problems.
#Befunge
Befunge
8 >:"2("*+::::4/+\"d"/-\45v @_^#`"y": +1$<_v#%7+1+/*:*< >:#,_>$:.55+,^ >0" ,52 ceD"
http://rosettacode.org/wiki/Day_of_the_week
Day of the week
A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January). Task In what years between 2008 and 2121 will the 25th of December be a Sunday? Using any standard date handling libraries of your programming language; compare the dates calculated with the output of other languages to discover any anomalies in the handling of dates which may be due to, for example, overflow in types used to represent dates/times similar to   y2k   type problems.
#Bracmat
Bracmat
{ Calculate day of week in proleptic Gregorian calendar. Sunday == 0. } ( wday = year month day adjustment mm yy .  !arg:(?year,?month,?day) & div$(14+-1*!month,12):?adjustment & !month+12*!adjustment+-2:?mm & !year+-1*!adjustment:?yy & mod $ (  !day + div$(13*!mm+-1,5) + !yy + div$(!yy,4) + -1*div$(!yy,100) + div$(!yy,400) , 7 ) ) & 2008:?y & whl ' ( !y:~>2121 & ( wday$(!y,12,25):0 & put$(str$(!y "-12-25\n")) | ) & 1+!y:?y ) & done;
http://rosettacode.org/wiki/CUSIP
CUSIP
This page uses content from Wikipedia. The original article was at CUSIP. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) A   CUSIP   is a nine-character alphanumeric code that identifies a North American financial security for the purposes of facilitating clearing and settlement of trades. The CUSIP was adopted as an American National Standard under Accredited Standards X9.6. Task Ensure the last digit   (i.e., the   check digit)   of the CUSIP code (the 1st column) is correct, against the following:   037833100       Apple Incorporated   17275R102       Cisco Systems   38259P508       Google Incorporated   594918104       Microsoft Corporation   68389X106       Oracle Corporation   (incorrect)   68389X105       Oracle Corporation Example pseudo-code below. algorithm Cusip-Check-Digit(cusip) is Input: an 8-character CUSIP   sum := 0 for 1 ≤ i ≤ 8 do c := the ith character of cusip if c is a digit then v := numeric value of the digit c else if c is a letter then p := ordinal position of c in the alphabet (A=1, B=2...) v := p + 9 else if c = "*" then v := 36 else if c = "@" then v := 37 else if' c = "#" then v := 38 end if if i is even then v := v × 2 end if   sum := sum + int ( v div 10 ) + v mod 10 repeat   return (10 - (sum mod 10)) mod 10 end function See related tasks SEDOL ISIN
#Ada
Ada
with Ada.Text_IO;   procedure Cusip_Test is use Ada.Text_IO;   subtype Cusip is String (1 .. 9);   function Check_Cusip (Code : Cusip) return Boolean is Sum : Integer := 0; V  : Integer;   begin for I in Code'First .. Code'Last - 1 loop case Code (I) is when '0' .. '9' => V := Character'Pos (Code (I)) - Character'Pos ('0'); when 'A' .. 'Z' => V := Character'Pos (Code (I)) - Character'Pos ('A') + 10; when '*' => V := 36; when '@' => V := 37; when '#' => V := 38; when others => return False; end case;   if I mod 2 = 0 then V := V * 2; end if;   Sum := Sum + V / 10 + (V mod 10); end loop;   return (10 - (Sum mod 10)) mod 10 = Character'Pos (Code (Code'Last)) - Character'Pos ('0'); end Check_Cusip;   type Cusip_Array is array (Natural range <>) of Cusip;   Test_Array : Cusip_Array := ("037833100", "17275R102", "38259P508", "594918104", "68389X106", "68389X105"); begin for I in Test_Array'Range loop Put (Test_Array (I) & ": "); if Check_Cusip (Test_Array (I)) then Put_Line ("valid"); else Put_Line ("not valid"); end if; end loop; end Cusip_Test;
http://rosettacode.org/wiki/Date_format
Date format
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the   current date   in the formats of:   2007-11-23     and   Friday, November 23, 2007
#Action.21
Action!
DEFINE PTR="CARD"   TYPE Date=[ INT year BYTE month BYTE day]   PTR ARRAY DayOfWeeks(7) PTR ARRAY Months(12)   PROC Init() DayOfWeeks(0)="Sunday" DayOfWeeks(1)="Monday" DayOfWeeks(2)="Tuesday" DayOfWeeks(3)="Wednesday" DayOfWeeks(4)="Thursday" DayOfWeeks(5)="Friday" DayOfWeeks(6)="Saturday" Months(0)="January" Months(1)="February" Months(2)="March" Months(3)="April" Months(4)="May" Months(5)="June" Months(6)="July" Months(7)="August" Months(8)="September" Months(9)="October" Months(10)="November" Months(11)="December" RETURN   ;https://en.wikipedia.org/wiki/Determination_of_the_day_of_the_week#Sakamoto.27s_methods BYTE FUNC DayOfWeek(Date POINTER d) ;1<=m<=12, y>1752 BYTE ARRAY t=[0 3 2 5 0 3 5 1 4 6 2 4] BYTE res INT y   y=d.year IF d.month<3 THEN y==-1 FI res=(y+y/4-y/100+y/400+t(d.month-1)+d.day) MOD 7 RETURN (res)   PROC PrintB2(BYTE x) IF x<10 THEN Put('0) FI PrintB(x) RETURN   PROC PrintDateShort(Date POINTER d) PrintI(d.year) Put('-) PrintB2(d.month) Put('-) PrintB2(d.day) RETURN   PROC PrintDateLong(Date POINTER d) BYTE wd   wd=DayOfWeek(d) Print(DayOfWeeks(wd)) Print(", ") Print(Months(d.month-1)) Put(' ) PrintB(d.day) Print(", ") PrintI(d.year) RETURN   PROC Main() Date d   Init()    ;There is no function to get the current date  ;on Atari 8-bit computer d.year=2021 d.month=9 d.day=1   PrintDateShort(d) PutE() PrintDateLong(d) PutE() RETURN
http://rosettacode.org/wiki/Date_format
Date format
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the   current date   in the formats of:   2007-11-23     and   Friday, November 23, 2007
#Ada
Ada
with Ada.Calendar; use Ada.Calendar; with Ada.Calendar.Formatting; use Ada.Calendar.Formatting; with Ada.Text_IO; use Ada.Text_IO;   procedure Date_Format is function Image (Month : Month_Number) return String is begin case Month is when 1 => return "January"; when 2 => return "February"; when 3 => return "March"; when 4 => return "April"; when 5 => return "May"; when 6 => return "June"; when 7 => return "July"; when 8 => return "August"; when 9 => return "September"; when 10 => return "October"; when 11 => return "November"; when 12 => return "December"; end case; end Image; function Image (Day : Day_Name) return String is begin case Day is when Monday => return "Monday"; when Tuesday => return "Tuesday"; when Wednesday => return "Wednesday"; when Thursday => return "Thursday"; when Friday => return "Friday"; when Saturday => return "Saturday"; when Sunday => return "Sunday"; end case; end Image; Today : Time := Clock; begin Put_Line (Image (Today) (1..10)); Put_Line ( Image (Day_Of_Week (Today)) & ", " & Image (Ada.Calendar.Month (Today)) & Day_Number'Image (Ada.Calendar.Day (Today)) & "," & Year_Number'Image (Ada.Calendar.Year (Today)) ); end Date_Format;
http://rosettacode.org/wiki/Damm_algorithm
Damm algorithm
The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors. The algorithm is named after H. Michael Damm. Task Verify the checksum, stored as last digit of an input.
#APL
APL
damm←{⎕IO←0 tbl←⍉⍪0 3 1 7 5 9 8 6 4 2 tbl⍪← 7 0 9 2 1 5 4 8 6 3 tbl⍪← 4 2 0 6 8 7 1 3 5 9 tbl⍪← 1 7 5 0 9 8 3 7 2 6 tbl⍪← 6 1 2 3 0 4 5 9 7 8 tbl⍪← 3 6 7 4 2 0 9 5 8 1 tbl⍪← 5 8 6 9 7 2 0 1 3 4 tbl⍪← 8 9 4 5 3 6 2 0 1 7 tbl⍪← 9 4 3 8 6 1 7 2 0 5 tbl⍪← 2 5 8 1 4 3 6 7 9 0 0={tbl[⍵;⍺]}/⌽0,⍵ }
http://rosettacode.org/wiki/Damm_algorithm
Damm algorithm
The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors. The algorithm is named after H. Michael Damm. Task Verify the checksum, stored as last digit of an input.
#AppleScript
AppleScript
-- Return a check digit value for the given integer value or numeric string. -- The result is 0 if the input's last digit is already a valid check digit for it. on damm(n) set digits to {n mod 10} set n to n div 10 repeat until (n is 0) set beginning of digits to n mod 10 set n to n div 10 end repeat   script o property table : {0, 3, 1, 7, 5, 9, 8, 6, 4, 2, ¬ 7, 0, 9, 2, 1, 5, 4, 8, 6, 3, ¬ 4, 2, 0, 6, 8, 7, 1, 3, 5, 9, ¬ 1, 7, 5, 0, 9, 8, 3, 4, 2, 6, ¬ 6, 1, 2, 3, 0, 4, 5, 9, 7, 8, ¬ 3, 6, 7, 4, 2, 0, 9, 5, 8, 1, ¬ 5, 8, 6, 9, 7, 2, 0, 1, 3, 4, ¬ 8, 9, 4, 5, 3, 6, 2, 0, 1, 7, ¬ 9, 4, 3, 8, 6, 1, 7, 2, 0, 5, ¬ 2, 5, 8, 1, 4, 3, 6, 7, 9, 0} end script set interim to 0 repeat with d in digits set interim to item (interim * 10 + d + 1) of o's table -- AppleScript indices are 1-based. end repeat   return interim end damm   -- Task code: local testNumbers, possibilities, output, n set testNumbers to {5724, 57240, 572400, 87591, 100} -- Include a number with a check digit actually generated by the handler. tell (random number 1000000) to set end of testNumbers to it * 10 + (my damm(it)) set possibilities to {" is invalid", " is valid"} set output to {} repeat with n in testNumbers set end of output to (n as text) & item (((damm(n) is 0) as integer) + 1) of possibilities end repeat return output
http://rosettacode.org/wiki/Curzon_numbers
Curzon numbers
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1. Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1. Base here does not imply the radix of the counting system; rather the integer the equation is based on. All calculations should be done in base 10. Generalized Curzon numbers only exist for even base integers. Task Find and show the first 50 Generalized Curzon numbers for even base integers from 2 through 10. Stretch Find and show the one thousandth. See also Numbers Aplenty - Curzon numbers OEIS:A224486 - Numbers k such that 2*k+1 divides 2^k+1 (Curzon numbers) and even though it is not specifically mentioned that they are Curzon numbers: OEIS:A230076 - (A007521(n)-1)/4 (Generalized Curzon numbers with a base 4)
#Julia
Julia
isCurzon(n, k) = (BigInt(k)^n + 1) % (k * n + 1) == 0   function printcurzons(klow, khigh) for k in filter(iseven, klow:khigh) n, curzons = 0, Int[] while length(curzons) < 1000 isCurzon(n, k) && push!(curzons, n) n += 1 end println("Curzon numbers with k = $k:") foreach(p -> print(lpad(p[2], 5), p[1] % 25 == 0 ? "\n" : ""), enumerate(curzons[1:50])) println(" Thousandth Curzon with k = $k: ", curzons[1000]) end end   printcurzons(2, 10)  
http://rosettacode.org/wiki/Curzon_numbers
Curzon numbers
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1. Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1. Base here does not imply the radix of the counting system; rather the integer the equation is based on. All calculations should be done in base 10. Generalized Curzon numbers only exist for even base integers. Task Find and show the first 50 Generalized Curzon numbers for even base integers from 2 through 10. Stretch Find and show the one thousandth. See also Numbers Aplenty - Curzon numbers OEIS:A224486 - Numbers k such that 2*k+1 divides 2^k+1 (Curzon numbers) and even though it is not specifically mentioned that they are Curzon numbers: OEIS:A230076 - (A007521(n)-1)/4 (Generalized Curzon numbers with a base 4)
#Pascal
Pascal
  program CurzonNumbers; uses SysUtils; const MAX_CURZON_MEG = 100; RC_LINE_LENGTH = 66;   procedure ListCurzonNumbers( base : integer); var k, n, m, x, testBit, maxCurzon : uint64; nrHits : integer; lineOut : string; begin maxCurzon := 1000000*MAX_CURZON_MEG; k := uint64( base); nrHits := 0; n := 0; WriteLn; if Odd( base) then WriteLn( SysUtils.Format( 'Curzon numbers with base %d up to %d million', [base, MAX_CURZON_MEG])) else WriteLn( SysUtils.Format( 'First 50 Curzon numbers with base %d', [base])); lineOut := ''; repeat inc(n); // possible (generalized) Curzon number m := k*n + 1; // modulus testBit := 1; repeat testBit := testBit shl 1 until testBit > n; testBit := testBit shr 2; // Calculate k^n modulo m x := k; while testBit > 0 do begin x := (x*x) mod m; if (testBit and n) <> 0 then x := (x*k) mod m; testBit := testBit shr 1; end; // n is a Curzon number to base k iff k^n + 1 is divisible by m if (x + 1) mod m = 0 then begin inc( nrHits); if Odd( base) then lineOut := lineOut + ' ' + SysUtils.IntToStr( n) else if (nrHits <= 50) then lineOut := lineOut + SysUtils.Format( '%5d', [n]); if Length( lineOut) >= RC_LINE_LENGTH then begin WriteLn( lineOut); lineOut := ''; end else if (nrHits = 1000) then begin if lineOut <> '' then begin WriteLn( lineOut); lineOut := ''; end; WriteLn( SysUtils.Format( '1000th = %d', [n])); end; end; until (n = maxCurzon) or (nrHits = 1000); if lineOut <> '' then WriteLn( lineOut); end;   begin ListCurzonNumbers( 2); ListCurzonNumbers( 4); ListCurzonNumbers( 6); ListCurzonNumbers( 8); ListCurzonNumbers(10); ListCurzonNumbers( 3); ListCurzonNumbers( 5); ListCurzonNumbers( 7); ListCurzonNumbers( 9); ListCurzonNumbers(11); end.  
http://rosettacode.org/wiki/Cut_a_rectangle
Cut a rectangle
A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such paths for 2 × 2 and 4 × 3 rectangles are shown below. Write a program that calculates the number of different ways to cut an m × n rectangle. Optionally, show each of the cuts. Possibly related task: Maze generation for depth-first search.
#Eiffel
Eiffel
  class APPLICATION   create make   feature {NONE} -- Initialization   make -- Finds solution for cut a rectangle up to 10 x 10. local i, j, n: Integer r: GRID do n := 10 from i := 1 until i > n loop from j := 1 until j > i loop if i.bit_and (1) /= 1 or j.bit_and (1) /= 1 then create r.make (i, j) r.print_solution end j := j + 1 end i := i + 1 end end   end  
http://rosettacode.org/wiki/Cyclops_numbers
Cyclops numbers
A cyclops number is a number with an odd number of digits that has a zero in the center, but nowhere else. They are named so in tribute to the one eyed giants Cyclops from Greek mythology. Cyclops numbers can be found in any base. This task strictly is looking for cyclops numbers in base 10. There are many different classifications of cyclops numbers with minor differences in characteristics. In an effort to head off a whole series of tasks with tiny variations, we will cover several variants here. Task Find and display here on this page the first 50 cyclops numbers in base 10 (all of the sub tasks are restricted to base 10). Find and display here on this page the first 50 prime cyclops numbers. (cyclops numbers that are prime.) Find and display here on this page the first 50 blind prime cyclops numbers. (prime cyclops numbers that remain prime when "blinded"; the zero is removed from the center.) Find and display here on this page the first 50 palindromic prime cyclops numbers. (prime cyclops numbers that are palindromes.) Stretch Find and display the first cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first blind prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first palindromic prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. (Note: there are no cyclops numbers between ten million and one hundred million, they need to have an odd number of digits) See also OEIS A134808 - Cyclops numbers OEIS A134809 - Cyclops primes OEIS A329737 - Cyclops primes that remain prime after being "blinded" OEIS A136098 - Prime palindromic cyclops numbers
#Phix
Phix
with javascript_semantics atom t0 = time() function bump(sequence half) -- add a digit to valid halves -- eg {0} --> {1..9} (no zeroes) -- --> {11..99} ("") -- --> {111..999}, etc sequence res = {} for i=1 to length(half) do integer hi = half[i]*10 for digit=1 to 9 do res &= hi+digit end for end for return res end function procedure cyclops(string s="") sequence res = {}, half = {0} -- valid digits, see bump() integer left = 1, -- half[] before the 0 right = 0, -- half[] after the 0 hlen = 1, -- length(half) cpow = 10, -- cyclops power (of 10) bcpow = 1, -- blind cyclops power cn = 0 -- cyclops number (scratch) bool valid = false, bPrime = match("prime",s), bBlind = match("blind",s), bPalin = match("palindromic",s) while length(res)<50 or cn<=1e7 or not valid do right += 1 if right>hlen then right = 1 left += 1 if left>hlen then half = bump(half) hlen = length(half) cpow *= 10 bcpow *= 10 left = 1 end if end if integer lh = half[left], rh = half[right] cn = lh*cpow+rh -- cyclops number valid = not bPrime or is_prime(cn) if valid and bBlind then valid = is_prime(lh*bcpow+rh) end if if valid and bPalin then valid = sprintf("%d",lh) == reverse(sprintf("%d",rh)) end if if valid then res = append(res,sprintf("%7d",cn)) end if end while printf(1,"First 50 %scyclops numbers:\n%s\n",{s,join_by(res[1..50],1,10)}) printf(1,"First %scyclops number > 10,000,000: %s at (one based) index: %d\n\n", {s,res[$],length(res)}) end procedure cyclops() cyclops("prime ") cyclops("blind prime ") cyclops("palindromic prime ") ?elapsed(time()-t0)
http://rosettacode.org/wiki/Date_manipulation
Date manipulation
Task Given the date string "March 7 2009 7:30pm EST", output the time 12 hours later in any human-readable format. As extra credit, display the resulting time in a time zone different from your own.
#C.23
C#
class Program { static void Main(string[] args) { CultureInfo ci=CultureInfo.CreateSpecificCulture("en-US"); string dateString = "March 7 2009 7:30pm EST"; string format = "MMMM d yyyy h:mmtt z"; DateTime myDateTime = DateTime.ParseExact(dateString.Replace("EST","+6"),format,ci) ; DateTime newDateTime = myDateTime.AddHours(12).AddDays(1) ; Console.WriteLine(newDateTime.ToString(format).Replace("-5","EST")); //probably not the best way to do this   Console.ReadLine(); } }
http://rosettacode.org/wiki/Deal_cards_for_FreeCell
Deal cards for FreeCell
Free Cell is the solitaire card game that Paul Alfille introduced to the PLATO system in 1978. Jim Horne, at Microsoft, changed the name to FreeCell and reimplemented the game for DOS, then Windows. This version introduced 32000 numbered deals. (The FreeCell FAQ tells this history.) As the game became popular, Jim Horne disclosed the algorithm, and other implementations of FreeCell began to reproduce the Microsoft deals. These deals are numbered from 1 to 32000. Newer versions from Microsoft have 1 million deals, numbered from 1 to 1000000; some implementations allow numbers outside that range. The algorithm uses this linear congruential generator from Microsoft C: s t a t e n + 1 ≡ 214013 × s t a t e n + 2531011 ( mod 2 31 ) {\displaystyle state_{n+1}\equiv 214013\times state_{n}+2531011{\pmod {2^{31}}}} r a n d n = s t a t e n ÷ 2 16 {\displaystyle rand_{n}=state_{n}\div 2^{16}} r a n d n {\displaystyle rand_{n}} is in range 0 to 32767. Rosetta Code has another task, linear congruential generator, with code for this RNG in several languages. The algorithm follows: Seed the RNG with the number of the deal. Create an array of 52 cards: Ace of Clubs, Ace of Diamonds, Ace of Hearts, Ace of Spades, 2 of Clubs, 2 of Diamonds, and so on through the ranks: Ace, 2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen, King. The array indexes are 0 to 51, with Ace of Clubs at 0, and King of Spades at 51. Until the array is empty: Choose a random card at index ≡ next random number (mod array length). Swap this random card with the last card of the array. Remove this random card from the array. (Array length goes down by 1.) Deal this random card. Deal all 52 cards, face up, across 8 columns. The first 8 cards go in 8 columns, the next 8 cards go on the first 8 cards, and so on. Order to deal cards Game #1 Game #617 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 JD 2D 9H JC 5D 7H 7C 5H KD KC 9S 5S AD QC KH 3H 2S KS 9D QD JS AS AH 3C 4C 5C TS QH 4H AC 4D 7S 3S TD 4S TH 8H 2C JH 7D 6D 8S 8D QS 6C 3D 8C TC 6S 9C 2H 6H 7D AD 5C 3S 5S 8C 2D AH TD 7S QD AC 6D 8H AS KH TH QC 3H 9D 6S 8D 3D TC KD 5H 9S 3C 8S 7H 4D JS 4C QS 9C 9H 7C 6H 2C 2S 4S TS 2H 5D JC 6C JH QH JD KS KC 4H Deals can also be checked against FreeCell solutions to 1000000 games. (Summon a video solution, and it displays the initial deal.) Write a program to take a deal number and deal cards in the same order as this algorithm. The program may display the cards with ASCII, with Unicode, by drawing graphics, or any other way. Related tasks: Playing cards Card shuffles War Card_Game Poker hand_analyser Go Fish
#Objective-C
Objective-C
#define RMAX32 ((1U << 31) - 1)   //--------------------------------------------------------------------   @interface Rand : NSObject -(instancetype) initWithSeed: (int)seed; -(int) next; @property (nonatomic) long seed; @end   @implementation Rand -(instancetype) initWithSeed: (int)seed { if ((self = [super init])) { self.seed = seed; } return self; } -(int) next { return (int) ((_seed = (_seed * 214013 + 2531011) & RMAX32) >> 16); } @end   //--------------------------------------------------------------------   @interface Card : NSObject -(instancetype) initWithSequence: (int)n; -(instancetype) initWithValue: (int)v suit: (int)s; @property (nonatomic) int value; @property (nonatomic) int suit; @end   @implementation Card -(instancetype) initWithSequence: (int)n { return [self initWithValue:n/4 suit:n%4]; } -(instancetype) initWithValue: (int)v suit: (int)s { if ((self = [super init])) { _value = v; _suit = s; } return self; } -(NSString *) description { static NSString * const kSuits = @"♣♦♥♠"; static NSString * const kValues = @"A23456789TJQK"; return [NSString stringWithFormat:@"%C%C", [kValues characterAtIndex:_value], [kSuits characterAtIndex:_suit]]; } @end   //--------------------------------------------------------------------   @interface Deck : NSObject -(instancetype) initWithSeed: (int)seed; @property (nonatomic, strong) NSMutableArray *cards; @end   @implementation Deck -(instancetype) initWithSeed: (int)seed { if ((self = [super init])) { Rand *r = [[Rand alloc] initWithSeed:seed]; _cards = [NSMutableArray array]; for (int i = 0; i < 52; i++) [_cards addObject:[[Card alloc] initWithSequence:51 - i]]; for (int i = 0; i < 51; i++) [_cards exchangeObjectAtIndex:i withObjectAtIndex:51 - [r next] % (52 - i)]; } return self; } -(NSString *) description { NSMutableString *s = [NSMutableString string]; for (int i = 0; i < [_cards count]; i++) { [s appendString:[_cards[i] description]]; [s appendString:i%8==7 ? @"\n" : @" "]; } return s; } @end   //--------------------------------------------------------------------   int main(int argc, const char * argv[]) { @autoreleasepool { NSLog(@"Deck 1\n%@\n", [[Deck alloc] initWithSeed:1]); NSLog(@"Deck 617\n%@\n", [[Deck alloc] initWithSeed:617]); } return 0; }
http://rosettacode.org/wiki/Define_a_primitive_data_type
Define a primitive data type
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
#Rust
Rust
use std::convert::TryFrom;   mod test_mod { use std::convert::TryFrom; use std::fmt;   // Because the `i8` is not `pub` this cannot be directly constructed // by code outside this module #[derive(Copy, Clone, Debug)] pub struct TwoDigit(i8);   impl TryFrom<i8> for TwoDigit { type Error = &'static str;   fn try_from(value: i8) -> Result<Self, Self::Error> { if value < -99 || value > 99 { Err("Number cannot fit into two decimal digits") } else { Ok(TwoDigit(value)) } } }   impl Into<i8> for TwoDigit { fn into(self) -> i8 { self.0 } }   // This powers `println!`'s `{}` token. impl fmt::Display for TwoDigit { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { write!(f, "{}", self.0) } } }   pub fn main() { let foo = test_mod::TwoDigit::try_from(50).unwrap(); let bar: i8 = foo.into(); println!("{} == {}", foo, bar); }
http://rosettacode.org/wiki/Define_a_primitive_data_type
Define a primitive data type
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
#Scala
Scala
class TinyInt(val int: Byte) { import TinyInt._ require(int >= lower && int <= upper, "TinyInt out of bounds.")   override def toString = int.toString }   object TinyInt { val (lower, upper) = (1, 10)   def apply(i: Byte) = new TinyInt(i) }   val test = (TinyInt.lower to TinyInt.upper).map(n => TinyInt(n.toByte))
http://rosettacode.org/wiki/Day_of_the_week
Day of the week
A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January). Task In what years between 2008 and 2121 will the 25th of December be a Sunday? Using any standard date handling libraries of your programming language; compare the dates calculated with the output of other languages to discover any anomalies in the handling of dates which may be due to, for example, overflow in types used to represent dates/times similar to   y2k   type problems.
#C
C
#include <stdio.h>   /* Calculate day of week in proleptic Gregorian calendar. Sunday == 0. */ int wday(int year, int month, int day) { int adjustment, mm, yy;   adjustment = (14 - month) / 12; mm = month + 12 * adjustment - 2; yy = year - adjustment; return (day + (13 * mm - 1) / 5 + yy + yy / 4 - yy / 100 + yy / 400) % 7; }   int main() { int y;   for (y = 2008; y <= 2121; y++) { if (wday(y, 12, 25) == 0) printf("%04d-12-25\n", y); }   return 0; }
http://rosettacode.org/wiki/CUSIP
CUSIP
This page uses content from Wikipedia. The original article was at CUSIP. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) A   CUSIP   is a nine-character alphanumeric code that identifies a North American financial security for the purposes of facilitating clearing and settlement of trades. The CUSIP was adopted as an American National Standard under Accredited Standards X9.6. Task Ensure the last digit   (i.e., the   check digit)   of the CUSIP code (the 1st column) is correct, against the following:   037833100       Apple Incorporated   17275R102       Cisco Systems   38259P508       Google Incorporated   594918104       Microsoft Corporation   68389X106       Oracle Corporation   (incorrect)   68389X105       Oracle Corporation Example pseudo-code below. algorithm Cusip-Check-Digit(cusip) is Input: an 8-character CUSIP   sum := 0 for 1 ≤ i ≤ 8 do c := the ith character of cusip if c is a digit then v := numeric value of the digit c else if c is a letter then p := ordinal position of c in the alphabet (A=1, B=2...) v := p + 9 else if c = "*" then v := 36 else if c = "@" then v := 37 else if' c = "#" then v := 38 end if if i is even then v := v × 2 end if   sum := sum + int ( v div 10 ) + v mod 10 repeat   return (10 - (sum mod 10)) mod 10 end function See related tasks SEDOL ISIN
#ALGOL_68
ALGOL 68
BEGIN # returns TRUE if cusip is a valid CUSIP code # OP ISCUSIP = ( STRING cusip )BOOL: IF ( UPB cusip - LWB cusip ) /= 8 THEN # code is wrong length # FALSE ELSE # string is 9 characters long - check it is valid # STRING cusip digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*@#"[ AT 0 ]; INT check digit := 0; IF NOT char in string( cusip[ UPB cusip ], check digit, cusip digits ) THEN # invalid check digit # FALSE ELSE # OK so far compare the calculated check sum to the supplied one # INT sum := 0; INT c pos := LWB cusip - 1; FOR i TO 8 DO INT digit := 0; IF NOT char in string( cusip[ i + c pos ], digit, cusip digits ) THEN # invalid digit # digit := -999 FI; IF NOT ODD i THEN # even digit # digit *:= 2 FI; sum +:= ( digit OVER 10 ) + ( digit MOD 10 ) OD; ( 10 - ( sum MOD 10 ) ) MOD 10 = check digit FI FI ; # ISCUSIP #   # task test cases #   PROC test cusip = ( STRING cusip )VOID: print( ( cusip, IF ISCUSIP cusip THEN " valid" ELSE " invalid" FI, newline ) );   test cusip( "037833100" ); test cusip( "17275R102" ); test cusip( "38259P508" ); test cusip( "594918104" ); test cusip( "68389X106" ); test cusip( "68389X105" ) END
http://rosettacode.org/wiki/Date_format
Date format
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the   current date   in the formats of:   2007-11-23     and   Friday, November 23, 2007
#ALGOL_68
ALGOL 68
# define the layout of the date/time as provided by the call to local time # STRUCT ( INT sec, min, hour, mday, mon, year, wday, yday, isdst) tm = (6,5,4,3,2,1,7,~,8);   FORMAT # some useful format declarations # ymd repr = $4d,"-"2d,"-"2d$, month repr = $c("January","February","March","April","May","June","July", "August","September","October","November","December")$, week day repr = $c("Sunday","Monday","Tuesday","Wednesday", "Thursday","Friday","Saturday")$, dmdy repr = $f(week day repr)", "f(month repr)" "g(-0)", "g(-4)$,   mon = $c("Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec")$, wday = $c("Sun","Mon","Tue","Wed","Thu","Fri","Sat")$, tz = $c("MSK","MSD")$, unix time repr = $f(wday)" "f(mon)z-d," "dd,":"dd,":"dd," "f(tz)" "dddd$;   []INT now = local time;   printf((ymd repr, now[year OF tm:mday OF tm], $l$)); printf((dmdy repr, now[wday OF tm], now[mon OF tm], now[mday OF tm], now[year OF tm], $l$));   printf((unix time repr, now[wday OF tm], now[mon OF tm], now[mday OF tm], now[hour OF tm:sec OF tm], now[isdst OF tm]+1, now[year OF tm], $l$))
http://rosettacode.org/wiki/Damm_algorithm
Damm algorithm
The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors. The algorithm is named after H. Michael Damm. Task Verify the checksum, stored as last digit of an input.
#ARM_Assembly
ARM Assembly
.text .global _start @@@ Check if the zero-terminated ASCII string in [r0], @@@ which should contain a decimal number, has a @@@ matching check digit. Zero flag set if true, @@@ check digit returned in r0. damm: mov r1,#0 @ R1 = interim digit ldr r2,=3f @ R2 = table base address 1: ldrb r3,[r0],#1 @ Load byte tst r3,r3 @ Zero yet? beq 2f @ If so, stop sub r3,r3,#'0 @ Subtract ASCII 0 lsl r1,r1,#1 @ Table lookup add r1,r1,r1,lsl#2 @ R3 = R1*10 + R3 add r3,r1,r3 ldrb r1,[r2,r3] @ R1 = new interim digit b 1b @ Next value 2: movs r0,r1 @ Set flag according to r0. bx lr 3: .byte 0,3,1,7,5,9,8,6,4,2 @ Since the table is constant, .byte 7,0,9,2,1,5,4,8,6,3 @ it can be stored as part of .byte 4,2,0,6,8,7,1,3,5,9 @ the subroutine. .byte 1,7,5,0,9,8,3,4,2,6 @ This way the OS will even mark .byte 6,1,2,3,0,4,5,9,7,8 @ it as read-only, so we can .byte 3,6,7,4,2,0,9,5,8,1 @ be sure nothing changes it. .byte 5,8,6,9,7,2,0,1,3,4 .byte 8,9,4,5,3,6,2,0,1,7 .byte 9,4,3,8,6,1,7,2,0,5 .byte 2,5,8,1,4,3,6,7,9,0 .align 4 @ Instructions must be word-aligned @@@ Grab the argument from the command line, and see @@@ if it matches. _start: pop {r0} @ Is there even an argument? cmp r0,#2 movne r7,#1 @ If not, exit immediately swine #0 add sp,sp,#4 @ Discard program name pop {r0} @ Grab argument bl damm @ Check if it matches ldreq r1,=pass @ If yes, say 'pass' ldrne r1,=fail @ If not, say 'fail' mov r0,#1 @ Print string to stdout mov r2,#5 @ Both are 5 characters mov r7,#4 @ Write syscall = 4 swi #0 mov r0,#0 @ Exit mov r7,#1 swi #0 pass: .ascii "Pass\n" fail: .ascii "Fail\n"
http://rosettacode.org/wiki/Damm_algorithm
Damm algorithm
The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors. The algorithm is named after H. Michael Damm. Task Verify the checksum, stored as last digit of an input.
#Arturo
Arturo
table: [ [0 3 1 7 5 9 8 6 4 2] [7 0 9 2 1 5 4 8 6 3] [4 2 0 6 8 7 1 3 5 9] [1 7 5 0 9 8 3 4 2 6] [6 1 2 3 0 4 5 9 7 8] [3 6 7 4 2 0 9 5 8 1] [5 8 6 9 7 2 0 1 3 4] [8 9 4 5 3 6 2 0 1 7] [9 4 3 8 6 1 7 2 0 5] [2 5 8 1 4 3 6 7 9 0] ]   digits: function [x][map split x => [to :integer]] damm?: function [z][zero? fold digits z .seed: 0 => [get get table]]   test: function [str][ result: switch damm? str -> "valid" -> "invalid" print [str "is" result] ]   loop ["5724" "5727" "112946" "112949"] => test
http://rosettacode.org/wiki/Curzon_numbers
Curzon numbers
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1. Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1. Base here does not imply the radix of the counting system; rather the integer the equation is based on. All calculations should be done in base 10. Generalized Curzon numbers only exist for even base integers. Task Find and show the first 50 Generalized Curzon numbers for even base integers from 2 through 10. Stretch Find and show the one thousandth. See also Numbers Aplenty - Curzon numbers OEIS:A224486 - Numbers k such that 2*k+1 divides 2^k+1 (Curzon numbers) and even though it is not specifically mentioned that they are Curzon numbers: OEIS:A230076 - (A007521(n)-1)/4 (Generalized Curzon numbers with a base 4)
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
ClearAll[CurzonNumberQ] CurzonNumberQ[b_Integer][n_Integer]:=PowerMod[b,n,b n+1]==b n val=Select[Range[100000],CurzonNumberQ[2]]; Take[val,50] val[[1000]]   val=Select[Range[100000],CurzonNumberQ[4]]; Take[val,50] val[[1000]]   val=Select[Range[100000],CurzonNumberQ[6]]; Take[val,50] val[[1000]]   val=Select[Range[100000],CurzonNumberQ[8]]; Take[val,50] val[[1000]]   val=Select[Range[100000],CurzonNumberQ[10]]; Take[val,50] val[[1000]]
http://rosettacode.org/wiki/Curzon_numbers
Curzon numbers
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1. Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1. Base here does not imply the radix of the counting system; rather the integer the equation is based on. All calculations should be done in base 10. Generalized Curzon numbers only exist for even base integers. Task Find and show the first 50 Generalized Curzon numbers for even base integers from 2 through 10. Stretch Find and show the one thousandth. See also Numbers Aplenty - Curzon numbers OEIS:A224486 - Numbers k such that 2*k+1 divides 2^k+1 (Curzon numbers) and even though it is not specifically mentioned that they are Curzon numbers: OEIS:A230076 - (A007521(n)-1)/4 (Generalized Curzon numbers with a base 4)
#Perl
Perl
use strict; use warnings; use Math::AnyNum 'ipow';   sub curzon { my($base,$cnt) = @_; my($n,@C) = 0; while (++$n) { push @C, $n if 0 == (ipow($base,$n) + 1) % ($base * $n + 1); return @C if $cnt == @C; } }   my $upto = 50; for my $k (<2 4 6 8 10>) { my @C = curzon($k,1000); print "First $upto Curzon numbers using a base of $k:\n" . (sprintf "@{['%5d' x $upto]}", @C[0..$upto-1]) =~ s/(.{125})/$1\n/gr; print "Thousandth: $C[-1]\n\n"; }
http://rosettacode.org/wiki/Curzon_numbers
Curzon numbers
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1. Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1. Base here does not imply the radix of the counting system; rather the integer the equation is based on. All calculations should be done in base 10. Generalized Curzon numbers only exist for even base integers. Task Find and show the first 50 Generalized Curzon numbers for even base integers from 2 through 10. Stretch Find and show the one thousandth. See also Numbers Aplenty - Curzon numbers OEIS:A224486 - Numbers k such that 2*k+1 divides 2^k+1 (Curzon numbers) and even though it is not specifically mentioned that they are Curzon numbers: OEIS:A230076 - (A007521(n)-1)/4 (Generalized Curzon numbers with a base 4)
#Phix
Phix
with javascript_semantics include mpfr.e mpz {pow,z} = mpz_inits(2) for base=2 to 10 by 2 do printf(1,"The first 50 Curzon numbers using a base of %d:\n",base) integer count = 0, n = 1 mpz_set_si(pow,base) while true do mpz_add_ui(z,pow,1) integer d = base*n + 1 if mpz_divisible_ui_p(z,d) then count = count + 1 if count<=50 then printf(1,"%5d%s",{n,iff(remainder(count,25)=0?"\n":"")}) elsif count=1000 then printf(1,"One thousandth: %d\n\n",n) exit end if end if n += 1 mpz_mul_si(pow,pow,base) end while end for
http://rosettacode.org/wiki/Cyclotomic_polynomial
Cyclotomic polynomial
The nth Cyclotomic polynomial, for any positive integer n, is the unique irreducible polynomial of largest degree with integer coefficients that is a divisor of x^n − 1, and is not a divisor of x^k − 1 for any k < n. Task Find and print the first 30 cyclotomic polynomials. Find and print the order of the first 10 cyclotomic polynomials that have n or -n as a coefficient. See also Wikipedia article, Cyclotomic polynomial, showing ways to calculate them. The sequence A013594 with the smallest order of cyclotomic polynomial containing n or -n as a coefficient.
#C.2B.2B
C++
#include <algorithm> #include <iostream> #include <initializer_list> #include <map> #include <vector>   const int MAX_ALL_FACTORS = 100000; const int algorithm = 2; int divisions = 0;   //Note: Cyclotomic Polynomials have small coefficients. Not appropriate for general polynomial usage. class Term { private: long m_coefficient; long m_exponent;   public: Term(long c, long e) : m_coefficient(c), m_exponent(e) { // empty }   Term(const Term &t) : m_coefficient(t.m_coefficient), m_exponent(t.m_exponent) { // empty }   long coefficient() const { return m_coefficient; }   long degree() const { return m_exponent; }   Term operator -() const { return { -m_coefficient, m_exponent }; }   Term operator *(const Term &rhs) const { return { m_coefficient * rhs.m_coefficient, m_exponent + rhs.m_exponent }; }   Term operator +(const Term &rhs) const { if (m_exponent != rhs.m_exponent) { throw std::runtime_error("Exponents not equal"); } return { m_coefficient + rhs.m_coefficient, m_exponent }; }   friend std::ostream &operator<<(std::ostream &, const Term &); };   std::ostream &operator<<(std::ostream &os, const Term &t) { if (t.m_coefficient == 0) { return os << '0'; } if (t.m_exponent == 0) { return os << t.m_coefficient; } if (t.m_coefficient == 1) { if (t.m_exponent == 1) { return os << 'x'; } return os << "x^" << t.m_exponent; } if (t.m_coefficient == -1) { if (t.m_exponent == 1) { return os << "-x"; } return os << "-x^" << t.m_exponent; } if (t.m_exponent == 1) { return os << t.m_coefficient << 'x'; } return os << t.m_coefficient << "x^" << t.m_exponent; }   class Polynomial { public: std::vector<Term> polynomialTerms;   Polynomial() { polynomialTerms.push_back({ 0, 0 }); }   Polynomial(std::initializer_list<int> values) { if (values.size() % 2 != 0) { throw std::runtime_error("Length must be even."); }   bool ready = false; long t; for (auto v : values) { if (ready) { polynomialTerms.push_back({ t, v }); } else { t = v; } ready = !ready; } std::sort( polynomialTerms.begin(), polynomialTerms.end(), [](const Term &t, const Term &u) { return u.degree() < t.degree(); } ); }   Polynomial(const std::vector<Term> &termList) { if (termList.size() == 0) { polynomialTerms.push_back({ 0, 0 }); } else { for (auto t : termList) { if (t.coefficient() != 0) { polynomialTerms.push_back(t); } } if (polynomialTerms.size() == 0) { polynomialTerms.push_back({ 0, 0 }); } std::sort( polynomialTerms.begin(), polynomialTerms.end(), [](const Term &t, const Term &u) { return u.degree() < t.degree(); } ); } }   Polynomial(const Polynomial &p) : Polynomial(p.polynomialTerms) { // empty }   long leadingCoefficient() const { return polynomialTerms[0].coefficient(); }   long degree() const { return polynomialTerms[0].degree(); }   bool hasCoefficientAbs(int coeff) { for (auto term : polynomialTerms) { if (abs(term.coefficient()) == coeff) { return true; } } return false; }   Polynomial operator+(const Term &term) const { std::vector<Term> termList; bool added = false; for (size_t index = 0; index < polynomialTerms.size(); index++) { auto currentTerm = polynomialTerms[index]; if (currentTerm.degree() == term.degree()) { added = true; if (currentTerm.coefficient() + term.coefficient() != 0) { termList.push_back(currentTerm + term); } } else { termList.push_back(currentTerm); } } if (!added) { termList.push_back(term); } return Polynomial(termList); }   Polynomial operator*(const Term &term) const { std::vector<Term> termList; for (size_t index = 0; index < polynomialTerms.size(); index++) { auto currentTerm = polynomialTerms[index]; termList.push_back(currentTerm * term); } return Polynomial(termList); }   Polynomial operator+(const Polynomial &p) const { std::vector<Term> termList; int thisCount = polynomialTerms.size(); int polyCount = p.polynomialTerms.size(); while (thisCount > 0 || polyCount > 0) { if (thisCount == 0) { auto polyTerm = p.polynomialTerms[polyCount - 1]; termList.push_back(polyTerm); polyCount--; } else if (polyCount == 0) { auto thisTerm = polynomialTerms[thisCount - 1]; termList.push_back(thisTerm); thisCount--; } else { auto polyTerm = p.polynomialTerms[polyCount - 1]; auto thisTerm = polynomialTerms[thisCount - 1]; if (thisTerm.degree() == polyTerm.degree()) { auto t = thisTerm + polyTerm; if (t.coefficient() != 0) { termList.push_back(t); } thisCount--; polyCount--; } else if (thisTerm.degree() < polyTerm.degree()) { termList.push_back(thisTerm); thisCount--; } else { termList.push_back(polyTerm); polyCount--; } } } return Polynomial(termList); }   Polynomial operator/(const Polynomial &v) { divisions++;   Polynomial q; Polynomial r(*this); long lcv = v.leadingCoefficient(); long dv = v.degree(); while (r.degree() >= v.degree()) { long lcr = r.leadingCoefficient(); long s = lcr / lcv; Term term(s, r.degree() - dv); q = q + term; r = r + v * -term; }   return q; }   friend std::ostream &operator<<(std::ostream &, const Polynomial &); };   std::ostream &operator<<(std::ostream &os, const Polynomial &p) { auto it = p.polynomialTerms.cbegin(); auto end = p.polynomialTerms.cend(); if (it != end) { os << *it; it = std::next(it); } while (it != end) { if (it->coefficient() > 0) { os << " + " << *it; } else { os << " - " << -*it; } it = std::next(it); } return os; }   std::vector<int> getDivisors(int number) { std::vector<int> divisiors; long root = (long)sqrt(number); for (int i = 1; i <= root; i++) { if (number % i == 0) { divisiors.push_back(i); int div = number / i; if (div != i && div != number) { divisiors.push_back(div); } } } return divisiors; }   std::map<int, std::map<int, int>> allFactors;   std::map<int, int> getFactors(int number) { if (allFactors.find(number) != allFactors.end()) { return allFactors[number]; }   std::map<int, int> factors; if (number % 2 == 0) { auto factorsDivTwo = getFactors(number / 2); factors.insert(factorsDivTwo.begin(), factorsDivTwo.end()); if (factors.find(2) != factors.end()) { factors[2]++; } else { factors.insert(std::make_pair(2, 1)); } if (number < MAX_ALL_FACTORS) { allFactors.insert(std::make_pair(number, factors)); } return factors; } long root = (long)sqrt(number); long i = 3; while (i <= root) { if (number % i == 0) { auto factorsDivI = getFactors(number / i); factors.insert(factorsDivI.begin(), factorsDivI.end()); if (factors.find(i) != factors.end()) { factors[i]++; } else { factors.insert(std::make_pair(i, 1)); } if (number < MAX_ALL_FACTORS) { allFactors.insert(std::make_pair(number, factors)); } return factors; } i += 2; } factors.insert(std::make_pair(number, 1)); if (number < MAX_ALL_FACTORS) { allFactors.insert(std::make_pair(number, factors)); } return factors; }   std::map<int, Polynomial> COMPUTED; Polynomial cyclotomicPolynomial(int n) { if (COMPUTED.find(n) != COMPUTED.end()) { return COMPUTED[n]; }   if (n == 1) { // Polynomial: x - 1 Polynomial p({ 1, 1, -1, 0 }); COMPUTED.insert(std::make_pair(1, p)); return p; }   auto factors = getFactors(n); if (factors.find(n) != factors.end()) { // n prime std::vector<Term> termList; for (int index = 0; index < n; index++) { termList.push_back({ 1, index }); }   Polynomial cyclo(termList); COMPUTED.insert(std::make_pair(n, cyclo)); return cyclo; } else if (factors.size() == 2 && factors.find(2) != factors.end() && factors[2] == 1 && factors.find(n / 2) != factors.end() && factors[n / 2] == 1) { // n = 2p int prime = n / 2; std::vector<Term> termList; int coeff = -1;   for (int index = 0; index < prime; index++) { coeff *= -1; termList.push_back({ coeff, index }); }   Polynomial cyclo(termList); COMPUTED.insert(std::make_pair(n, cyclo)); return cyclo; } else if (factors.size() == 1 && factors.find(2) != factors.end()) { // n = 2^h int h = factors[2]; std::vector<Term> termList; termList.push_back({ 1, (int)pow(2, h - 1) }); termList.push_back({ 1, 0 });   Polynomial cyclo(termList); COMPUTED.insert(std::make_pair(n, cyclo)); return cyclo; } else if (factors.size() == 1 && factors.find(n) != factors.end()) { // n = p^k int p = 0; int k = 0; for (auto iter = factors.begin(); iter != factors.end(); ++iter) { p = iter->first; k = iter->second; } std::vector<Term> termList; for (int index = 0; index < p; index++) { termList.push_back({ 1, index * (int)pow(p, k - 1) }); }   Polynomial cyclo(termList); COMPUTED.insert(std::make_pair(n, cyclo)); return cyclo; } else if (factors.size() == 2 && factors.find(2) != factors.end()) { // n = 2^h * p^k int p = 0; for (auto iter = factors.begin(); iter != factors.end(); ++iter) { if (iter->first != 2) { p = iter->first; } }   std::vector<Term> termList; int coeff = -1; int twoExp = (int)pow(2, factors[2] - 1); int k = factors[p]; for (int index = 0; index < p; index++) { coeff *= -1; termList.push_back({ coeff, index * twoExp * (int)pow(p, k - 1) }); }   Polynomial cyclo(termList); COMPUTED.insert(std::make_pair(n, cyclo)); return cyclo; } else if (factors.find(2) != factors.end() && ((n / 2) % 2 == 1) && (n / 2) > 1) { // CP(2m)[x] = CP(-m)[x], n odd integer > 1 auto cycloDiv2 = cyclotomicPolynomial(n / 2); std::vector<Term> termList; for (auto term : cycloDiv2.polynomialTerms) { if (term.degree() % 2 == 0) { termList.push_back(term); } else { termList.push_back(-term); } }   Polynomial cyclo(termList); COMPUTED.insert(std::make_pair(n, cyclo)); return cyclo; }   // General Case   if (algorithm == 0) { // slow - uses basic definition auto divisors = getDivisors(n); // Polynomial: (x^n - 1) Polynomial cyclo({ 1, n, -1, 0 }); for (auto i : divisors) { auto p = cyclotomicPolynomial(i); cyclo = cyclo / p; }   COMPUTED.insert(std::make_pair(n, cyclo)); return cyclo; } else if (algorithm == 1) { // Faster. Remove Max divisor (and all divisors of max divisor) - only one divide for all divisors of Max Divisor auto divisors = getDivisors(n); int maxDivisor = INT_MIN; for (auto div : divisors) { maxDivisor = std::max(maxDivisor, div); } std::vector<int> divisorExceptMax; for (auto div : divisors) { if (maxDivisor % div != 0) { divisorExceptMax.push_back(div); } }   // Polynomial: ( x^n - 1 ) / ( x^m - 1 ), where m is the max divisor auto cyclo = Polynomial({ 1, n, -1, 0 }) / Polynomial({ 1, maxDivisor, -1, 0 }); for (int i : divisorExceptMax) { auto p = cyclotomicPolynomial(i); cyclo = cyclo / p; }   COMPUTED.insert(std::make_pair(n, cyclo)); return cyclo; } else if (algorithm == 2) { // Fastest // Let p ; q be primes such that p does not divide n, and q q divides n. // Then CP(np)[x] = CP(n)[x^p] / CP(n)[x] int m = 1; auto cyclo = cyclotomicPolynomial(m); std::vector<int> primes; for (auto iter = factors.begin(); iter != factors.end(); ++iter) { primes.push_back(iter->first); } std::sort(primes.begin(), primes.end()); for (auto prime : primes) { // CP(m)[x] auto cycloM = cyclo; // Compute CP(m)[x^p]. std::vector<Term> termList; for (auto t : cycloM.polynomialTerms) { termList.push_back({ t.coefficient(), t.degree() * prime }); } cyclo = Polynomial(termList) / cycloM; m = m * prime; } // Now, m is the largest square free divisor of n int s = n / m; // Compute CP(n)[x] = CP(m)[x^s] std::vector<Term> termList; for (auto t : cyclo.polynomialTerms) { termList.push_back({ t.coefficient(), t.degree() * s }); }   cyclo = Polynomial(termList); COMPUTED.insert(std::make_pair(n, cyclo)); return cyclo; } else { throw std::runtime_error("Invalid algorithm"); } }   int main() { // initialization std::map<int, int> factors; factors.insert(std::make_pair(2, 1)); allFactors.insert(std::make_pair(2, factors));   // rest of main std::cout << "Task 1: cyclotomic polynomials for n <= 30:\n"; for (int i = 1; i <= 30; i++) { auto p = cyclotomicPolynomial(i); std::cout << "CP[" << i << "] = " << p << '\n'; }   std::cout << "Task 2: Smallest cyclotomic polynomial with n or -n as a coefficient:\n"; int n = 0; for (int i = 1; i <= 10; i++) { while (true) { n++; auto cyclo = cyclotomicPolynomial(n); if (cyclo.hasCoefficientAbs(i)) { std::cout << "CP[" << n << "] has coefficient with magnitude = " << i << '\n'; n--; break; } } }   return 0; }
http://rosettacode.org/wiki/Cut_a_rectangle
Cut a rectangle
A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such paths for 2 × 2 and 4 × 3 rectangles are shown below. Write a program that calculates the number of different ways to cut an m × n rectangle. Optionally, show each of the cuts. Possibly related task: Maze generation for depth-first search.
#Elixir
Elixir
import Integer   defmodule Rectangle do def cut_it(h, w) when is_odd(h) and is_odd(w), do: 0 def cut_it(h, w) when is_odd(h), do: cut_it(w, h) def cut_it(_, 1), do: 1 def cut_it(h, 2), do: h def cut_it(2, w), do: w def cut_it(h, w) do grid = List.duplicate(false, (h + 1) * (w + 1)) t = div(h, 2) * (w + 1) + div(w, 2) if is_odd(w) do grid = grid |> List.replace_at(t, true) |> List.replace_at(t+1, true) walk(h, w, div(h, 2), div(w, 2) - 1, grid) + walk(h, w, div(h, 2) - 1, div(w, 2), grid) * 2 else grid = grid |> List.replace_at(t, true) count = walk(h, w, div(h, 2), div(w, 2) - 1, grid) if h == w, do: count * 2, else: count + walk(h, w, div(h, 2) - 1, div(w, 2), grid) end end   defp walk(h, w, y, x, grid, count\\0) defp walk(h, w, y, x,_grid, count) when y in [0,h] or x in [0,w], do: count+1 defp walk(h, w, y, x, grid, count) do blen = (h + 1) * (w + 1) - 1 t = y * (w + 1) + x grid = grid |> List.replace_at(t, true) |> List.replace_at(blen-t, true) Enum.reduce(next(w), count, fn {nt, dy, dx}, cnt -> if Enum.at(grid, t+nt), do: cnt, else: cnt + walk(h, w, y+dy, x+dx, grid) end) end   defp next(w), do: [{w+1, 1, 0}, {-w-1, -1, 0}, {-1, 0, -1}, {1, 0, 1}] # {next,dy,dx} end   Enum.each(1..9, fn w -> Enum.each(1..w, fn h -> if is_even(w * h), do: IO.puts "#{w} x #{h}: #{Rectangle.cut_it(w, h)}" end) end)
http://rosettacode.org/wiki/Cyclops_numbers
Cyclops numbers
A cyclops number is a number with an odd number of digits that has a zero in the center, but nowhere else. They are named so in tribute to the one eyed giants Cyclops from Greek mythology. Cyclops numbers can be found in any base. This task strictly is looking for cyclops numbers in base 10. There are many different classifications of cyclops numbers with minor differences in characteristics. In an effort to head off a whole series of tasks with tiny variations, we will cover several variants here. Task Find and display here on this page the first 50 cyclops numbers in base 10 (all of the sub tasks are restricted to base 10). Find and display here on this page the first 50 prime cyclops numbers. (cyclops numbers that are prime.) Find and display here on this page the first 50 blind prime cyclops numbers. (prime cyclops numbers that remain prime when "blinded"; the zero is removed from the center.) Find and display here on this page the first 50 palindromic prime cyclops numbers. (prime cyclops numbers that are palindromes.) Stretch Find and display the first cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first blind prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first palindromic prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. (Note: there are no cyclops numbers between ten million and one hundred million, they need to have an odd number of digits) See also OEIS A134808 - Cyclops numbers OEIS A134809 - Cyclops primes OEIS A329737 - Cyclops primes that remain prime after being "blinded" OEIS A136098 - Prime palindromic cyclops numbers
#Raku
Raku
use Lingua::EN::Numbers;   my @cyclops = 0, |flat lazy ^∞ .map: -> $exp { my @oom = (exp($exp, 10) ..^ exp($exp + 1, 10)).grep: { !.contains: 0 } |@oom.hyper.map: { $_ ~ 0 «~« @oom } }   my @prime-cyclops = @cyclops.grep: { .is-prime };   for '', @cyclops, 'prime ', @prime-cyclops, 'blind prime ', @prime-cyclops.grep( { .trans('0' => '').is-prime } ), 'palindromic prime ', @prime-cyclops.grep( { $_ eq .flip } ) -> $type, $iterator { say "\n\nFirst 50 {$type}cyclops numbers:\n" ~ $iterator[^50].batch(10)».fmt("%7d").join("\n") ~ "\n\nFirst {$type}cyclops number > 10,000,000: " ~ comma($iterator.first: * > 1e7 ) ~ " - at (zero based) index: " ~ comma $iterator.first: * > 1e7, :k; }
http://rosettacode.org/wiki/Date_manipulation
Date manipulation
Task Given the date string "March 7 2009 7:30pm EST", output the time 12 hours later in any human-readable format. As extra credit, display the resulting time in a time zone different from your own.
#C.2B.2B
C++
#include <string> #include <iostream> #include <boost/date_time/local_time/local_time.hpp> #include <sstream> #include <boost/date_time/gregorian/gregorian.hpp> #include <vector> #include <boost/algorithm/string.hpp> #include <cstdlib> #include <locale>     int main( ) { std::string datestring ("March 7 2009 7:30pm EST" ) ; //we must first parse the date string into a date , a time and a time //zone part , to take account of present restrictions in the input facets //of the Boost::DateTime library used for this example std::vector<std::string> elements ; //parsing the date string boost::split( elements , datestring , boost::is_any_of( " " ) ) ; std::string datepart = elements[ 0 ] + " " + "0" + elements[ 1 ] + " " + elements[ 2 ] ; //we must add 0 to avoid trouble with the boost::date_input format strings std::string timepart = elements[ 3 ] ; std::string timezone = elements[ 4 ] ; const char meridians[ ] = { 'a' , 'p' } ; //we have to find out if the time is am or pm, to change the hours appropriately std::string::size_type found = timepart.find_first_of( meridians, 0 ) ; std::string twelve_hour ( timepart.substr( found , 1 ) ) ; timepart = timepart.substr( 0 , found ) ; //we chop off am or pm elements.clear( ) ; boost::split( elements , timepart , boost::is_any_of ( ":" ) ) ; long hour = std::atol( (elements.begin( ))->c_str( ) ) ;// hours in the string if ( twelve_hour == "p" ) //it's post meridian, we're converting to 24-hour-clock hour += 12 ; long minute = std::atol( ( elements.begin( ) + 1)->c_str( ) ) ; boost::local_time::tz_database tz_db ; tz_db.load_from_file( "/home/ulrich/internetpages/date_time_zonespec.csv" ) ; //according to the time zone database, this corresponds to one possible EST time zone boost::local_time::time_zone_ptr dyc = tz_db.time_zone_from_region( "America/New_York" ) ; //this is the string input format to initialize the date field boost::gregorian::date_input_facet *f = new boost::gregorian::date_input_facet( "%B %d %Y" ) ; std::stringstream ss ; ss << datepart ; ss.imbue( std::locale( std::locale::classic( ) , f ) ) ; boost::gregorian::date d ; ss >> d ; boost::posix_time::time_duration td ( hour , minute , 0 ) ; //that's how we initialize the New York local time , by using date and adding //time duration with values coming from parsed date input string boost::local_time::local_date_time lt ( d , td , dyc , boost::local_time::local_date_time::NOT_DATE_TIME_ON_ERROR ) ; std::cout << "local time: " << lt << '\n' ; ss.str( "" ) ; ss << lt ; //we have to add 12 hours, so a new time duration object is created boost::posix_time::time_duration td2 (12 , 0 , 0 , 0 ) ; boost::local_time::local_date_time ltlater = lt + td2 ; //local time 12 hours later boost::gregorian::date_facet *f2 = new boost::gregorian::date_facet( "%B %d %Y , %R %Z" ) ; std::cout.imbue( std::locale( std::locale::classic( ) , f2 ) ) ; std::cout << "12 hours after " << ss.str( ) << " it is " << ltlater << " !\n" ; //what's New York time in the Berlin time zone ? boost::local_time::time_zone_ptr bt = tz_db.time_zone_from_region( "Europe/Berlin" ) ; std::cout.imbue( std::locale( "de_DE.UTF-8" ) ) ; //choose the output forman appropriate for the time zone std::cout << "This corresponds to " << ltlater.local_time_in( bt ) << " in Berlin!\n" ; return 0 ; }  
http://rosettacode.org/wiki/Deal_cards_for_FreeCell
Deal cards for FreeCell
Free Cell is the solitaire card game that Paul Alfille introduced to the PLATO system in 1978. Jim Horne, at Microsoft, changed the name to FreeCell and reimplemented the game for DOS, then Windows. This version introduced 32000 numbered deals. (The FreeCell FAQ tells this history.) As the game became popular, Jim Horne disclosed the algorithm, and other implementations of FreeCell began to reproduce the Microsoft deals. These deals are numbered from 1 to 32000. Newer versions from Microsoft have 1 million deals, numbered from 1 to 1000000; some implementations allow numbers outside that range. The algorithm uses this linear congruential generator from Microsoft C: s t a t e n + 1 ≡ 214013 × s t a t e n + 2531011 ( mod 2 31 ) {\displaystyle state_{n+1}\equiv 214013\times state_{n}+2531011{\pmod {2^{31}}}} r a n d n = s t a t e n ÷ 2 16 {\displaystyle rand_{n}=state_{n}\div 2^{16}} r a n d n {\displaystyle rand_{n}} is in range 0 to 32767. Rosetta Code has another task, linear congruential generator, with code for this RNG in several languages. The algorithm follows: Seed the RNG with the number of the deal. Create an array of 52 cards: Ace of Clubs, Ace of Diamonds, Ace of Hearts, Ace of Spades, 2 of Clubs, 2 of Diamonds, and so on through the ranks: Ace, 2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen, King. The array indexes are 0 to 51, with Ace of Clubs at 0, and King of Spades at 51. Until the array is empty: Choose a random card at index ≡ next random number (mod array length). Swap this random card with the last card of the array. Remove this random card from the array. (Array length goes down by 1.) Deal this random card. Deal all 52 cards, face up, across 8 columns. The first 8 cards go in 8 columns, the next 8 cards go on the first 8 cards, and so on. Order to deal cards Game #1 Game #617 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 JD 2D 9H JC 5D 7H 7C 5H KD KC 9S 5S AD QC KH 3H 2S KS 9D QD JS AS AH 3C 4C 5C TS QH 4H AC 4D 7S 3S TD 4S TH 8H 2C JH 7D 6D 8S 8D QS 6C 3D 8C TC 6S 9C 2H 6H 7D AD 5C 3S 5S 8C 2D AH TD 7S QD AC 6D 8H AS KH TH QC 3H 9D 6S 8D 3D TC KD 5H 9S 3C 8S 7H 4D JS 4C QS 9C 9H 7C 6H 2C 2S 4S TS 2H 5D JC 6C JH QH JD KS KC 4H Deals can also be checked against FreeCell solutions to 1000000 games. (Summon a video solution, and it displays the initial deal.) Write a program to take a deal number and deal cards in the same order as this algorithm. The program may display the cards with ASCII, with Unicode, by drawing graphics, or any other way. Related tasks: Playing cards Card shuffles War Card_Game Poker hand_analyser Go Fish
#OCaml
OCaml
let srnd x = (* since OCaml's built-in int type is at least 31 (note: not 32) bits wide, and this problem takes mod 2^31, it is just enough if we treat it as an unsigned integer, which means taking the logical right shift *) let seed = ref x in fun () -> seed := (!seed * 214013 + 2531011) land 0x7fffffff; !seed lsr 16   let deal s = let rnd = srnd s in let t = Array.init 52 (fun i -> i) in let cards = Array.init 52 (fun j -> let n = 52 - j in let i = rnd() mod n in let this = t.(i) in t.(i) <- t.(pred n); this) in (cards)   let show cards = let suits = "CDHS" and nums = "A23456789TJQK" in Array.iteri (fun i card -> Printf.printf "%c%c%c" nums.[card / 4] suits.[card mod 4] (if (i mod 8) = 7 then '\n' else ' ') ) cards; print_newline()   let () = let s = try int_of_string Sys.argv.(1) with _ -> 11982 in Printf.printf "Deal %d:\n" s; let cards = deal s in show cards
http://rosettacode.org/wiki/Define_a_primitive_data_type
Define a primitive data type
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
#Sidef
Sidef
subset Integer < Number { .is_int } subset MyIntLimit < Integer { . ~~ (1 ..^ 10) }   class MyInt(value < MyIntLimit) {   method to_s { value.to_s } method get_value { value.get_value }   method ==(Number x) { value == x } method ==(MyInt x) { value == x.value }   method AUTOLOAD(_, name, *args) { var results = [value.(name)(args.map {|n| Number(n) }...)] results.map{|r| r.kind_of(Number) ? MyInt(r.int) : r}... } }   # ## Example: # var a = MyInt(2) # creates a new object of type `MyInt` a += 7 # adds 7 to a say a # => 9 say a/2 # => 4   var b = (a - 3) # b is of type `MyInt` say b # => 6   say a.as_hex.dump # => "9" -- an hexadecimal string   a -= 6 # a=3 var c = (a + b) # MyInt(3) + MyInt(6) say c # => 9 say c.class # => MyInt   a *= 2 # a=6 say a+b # error: class `MyInt` does not match MyInt(12)
http://rosettacode.org/wiki/Day_of_the_week
Day of the week
A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January). Task In what years between 2008 and 2121 will the 25th of December be a Sunday? Using any standard date handling libraries of your programming language; compare the dates calculated with the output of other languages to discover any anomalies in the handling of dates which may be due to, for example, overflow in types used to represent dates/times similar to   y2k   type problems.
#C.23
C#
using System;   class Program { static void Main(string[] args) { for (int i = 2008; i <= 2121; i++) { DateTime date = new DateTime(i, 12, 25); if (date.DayOfWeek == DayOfWeek.Sunday) { Console.WriteLine(date.ToString("dd MMM yyyy")); } } } }
http://rosettacode.org/wiki/CUSIP
CUSIP
This page uses content from Wikipedia. The original article was at CUSIP. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) A   CUSIP   is a nine-character alphanumeric code that identifies a North American financial security for the purposes of facilitating clearing and settlement of trades. The CUSIP was adopted as an American National Standard under Accredited Standards X9.6. Task Ensure the last digit   (i.e., the   check digit)   of the CUSIP code (the 1st column) is correct, against the following:   037833100       Apple Incorporated   17275R102       Cisco Systems   38259P508       Google Incorporated   594918104       Microsoft Corporation   68389X106       Oracle Corporation   (incorrect)   68389X105       Oracle Corporation Example pseudo-code below. algorithm Cusip-Check-Digit(cusip) is Input: an 8-character CUSIP   sum := 0 for 1 ≤ i ≤ 8 do c := the ith character of cusip if c is a digit then v := numeric value of the digit c else if c is a letter then p := ordinal position of c in the alphabet (A=1, B=2...) v := p + 9 else if c = "*" then v := 36 else if c = "@" then v := 37 else if' c = "#" then v := 38 end if if i is even then v := v × 2 end if   sum := sum + int ( v div 10 ) + v mod 10 repeat   return (10 - (sum mod 10)) mod 10 end function See related tasks SEDOL ISIN
#ALGOL_W
ALGOL W
begin  % returns true if cusip is a valid CUSIP code % logical procedure isCusip ( string(9) value cusip ) ; begin  % returns the base 39 digit corresponding to a character of a CUSIP code % integer procedure cusipDigit( string(1) value cChar ) ; if cChar >= "0" and cChar <= "9" then ( decode( cChar ) - decode( "0" ) ) else if cChar >= "A" and cChar <= "Z" then ( decode( cChar ) - decode( "A" ) ) + 10 else if cChar = "*" then 36 else if cChar = "@" then 37 else if cChar = "#" then 38 else  % invalid digit % -999 ;   integer checkDigit, sum; checkDigit := cusipDigit( cusip( 8 // 1 ) ); for cPos := 1 until 8 do begin integer digit; digit := cusipDigit( cusip( ( cPos - 1 ) // 1 ) ); if not odd( cPos ) then digit := digit * 2; sum := sum + ( digit div 10 ) + ( digit rem 10 ) end for_cPos ; ( ( 10 - ( sum rem 10 ) ) rem 10 ) = checkDigit end isCusip ;   begin % task test cases % procedure testCusip ( string(9) value cusip ) ; write( s_w := 0, cusip, if isCusip( cusip ) then " valid" else " invalid" );   testCusip( "037833100" ); testCusip( "17275R102" ); testCusip( "38259P508" ); testCusip( "594918104" ); testCusip( "68389X106" ); testCusip( "68389X105" ) end testCases end.
http://rosettacode.org/wiki/CUSIP
CUSIP
This page uses content from Wikipedia. The original article was at CUSIP. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) A   CUSIP   is a nine-character alphanumeric code that identifies a North American financial security for the purposes of facilitating clearing and settlement of trades. The CUSIP was adopted as an American National Standard under Accredited Standards X9.6. Task Ensure the last digit   (i.e., the   check digit)   of the CUSIP code (the 1st column) is correct, against the following:   037833100       Apple Incorporated   17275R102       Cisco Systems   38259P508       Google Incorporated   594918104       Microsoft Corporation   68389X106       Oracle Corporation   (incorrect)   68389X105       Oracle Corporation Example pseudo-code below. algorithm Cusip-Check-Digit(cusip) is Input: an 8-character CUSIP   sum := 0 for 1 ≤ i ≤ 8 do c := the ith character of cusip if c is a digit then v := numeric value of the digit c else if c is a letter then p := ordinal position of c in the alphabet (A=1, B=2...) v := p + 9 else if c = "*" then v := 36 else if c = "@" then v := 37 else if' c = "#" then v := 38 end if if i is even then v := v × 2 end if   sum := sum + int ( v div 10 ) + v mod 10 repeat   return (10 - (sum mod 10)) mod 10 end function See related tasks SEDOL ISIN
#AppleScript
AppleScript
use AppleScript version "2.4" use framework "Foundation" use scripting additions     -- isCusip :: String -> Bool on isCusip(s) set cs to "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*&#" set ns to mapMaybe(elemIndex(cs), s)   script go on |λ|(f, x) set fx to apply(f, x) (fx div 10) + (fx mod 10) end |λ| end script   9 = length of ns and item -1 of ns = (10 - (sum(zipWith(go, ¬ cycle({my identity, my double}), ¬ take(8, ns))) mod 10)) mod 10 end isCusip     -------------------------- TEST --------------------------- on run script test on |λ|(s) s & " -> " & isCusip(s) end |λ| end script   unlines(map(test, ¬ {"037833100", "17275R102", "38259P508", ¬ "594918104", "68389X106", "68389X105"})) end run   -- 037833100 -> true -- 17275R102 -> true -- 38259P508 -> true -- 594918104 -> true -- 68389X106 -> false -- 68389X105 -> true     -------------------- GENERIC FUNCTIONS --------------------   -- Just :: a -> Maybe a on Just(x) -- Constructor for an inhabited Maybe (option type) value. -- Wrapper containing the result of a computation. {type:"Maybe", Nothing:false, Just:x} end Just     -- Nothing :: Maybe a on Nothing() -- Constructor for an empty Maybe (option type) value. -- Empty wrapper returned where a computation is not possible. {type:"Maybe", Nothing:true} end Nothing     -- Tuple (,) :: a -> b -> (a, b) on Tuple(a, b) -- Constructor for a pair of values, possibly of two different types. {type:"Tuple", |1|:a, |2|:b, length:2} end Tuple     -- apply ($) :: (a -> b) -> a -> b on apply(f, x) -- The value of f(x) mReturn(f)'s |λ|(x) end apply     -- cycle :: [a] -> Generator [a] on cycle(xs) script property lng : 1 + (length of xs) property i : missing value on |λ|() if missing value is i then set i to 1 else set nxt to (1 + i) mod lng if 0 = ((1 + i) mod lng) then set i to 1 else set i to nxt end if end if return item i of xs end |λ| end script end cycle     -- double :: Num -> Num on double(x) 2 * x end double     -- elemIndex :: Eq a => [a] -> a -> Maybe Int on elemIndex(xs) script on |λ|(x) set lng to length of xs repeat with i from 1 to lng if x = (item i of xs) then return Just(i - 1) end repeat return Nothing() end |λ| end script end elemIndex     -- identity :: a -> a on identity(x) -- The argument unchanged. x end identity     -- foldl :: (a -> b -> a) -> a -> [b] -> a on foldl(f, startValue, xs) tell mReturn(f) set v to startValue set lng to length of xs repeat with i from 1 to lng set v to |λ|(v, item i of xs, i, xs) end repeat return v end tell end foldl     -- length :: [a] -> Int on |length|(xs) set c to class of xs if list is c or string is c then length of xs else (2 ^ 29 - 1) -- (maxInt - simple proxy for non-finite) end if end |length|     -- map :: (a -> b) -> [a] -> [b] on map(f, xs) -- The list obtained by applying f -- to each element of xs. tell mReturn(f) set lng to length of xs set lst to {} repeat with i from 1 to lng set end of lst to |λ|(item i of xs, i, xs) end repeat return lst end tell end map     -- The mapMaybe function is a version of map which can throw out -- elements. In particular, the functional argument returns -- something of type Maybe b. If this is Nothing, no element is -- added on to the result list. If it just Just b, then b is -- included in the result list. -- mapMaybe :: (a -> Maybe b) -> [a] -> [b] on mapMaybe(mf, xs) script property g : mReturn(mf) on |λ|(a, x) set mb to g's |λ|(x) if Nothing of mb then a else a & (Just of mb) end if end |λ| end script foldl(result, {}, xs) end mapMaybe     -- min :: Ord a => a -> a -> a on min(x, y) if y < x then y else x end if end min     -- mReturn :: First-class m => (a -> b) -> m (a -> b) on mReturn(f) -- 2nd class handler function lifted into 1st class script wrapper. if script is class of f then f else script property |λ| : f end script end if end mReturn     -- sum :: [Num] -> Num on sum(xs) script add on |λ|(a, b) a + b end |λ| end script   foldl(add, 0, xs) end sum     -- take :: Int -> [a] -> [a] -- take :: Int -> String -> String on take(n, xs) set c to class of xs if list is c then if 0 < n then items 1 thru min(n, length of xs) of xs else {} end if else if string is c then if 0 < n then text 1 thru min(n, length of xs) of xs else "" end if else if script is c then set ys to {} repeat with i from 1 to n set v to |λ|() of xs if missing value is v then return ys else set end of ys to v end if end repeat return ys else missing value end if end take     -- unlines :: [String] -> String on unlines(xs) -- A single string formed by the intercalation -- of a list of strings with the newline character. set {dlm, my text item delimiters} to ¬ {my text item delimiters, linefeed} set str to xs as text set my text item delimiters to dlm str end unlines     -- zipWith :: (a -> b -> c) -> [a] -> [b] -> [c] on zipWith(f, xs, ys) set lng to min(|length|(xs), |length|(ys)) if 1 > lng then return {} set xs_ to take(lng, xs) -- Allow for non-finite set ys_ to take(lng, ys) -- generators like cycle etc set lst to {} tell mReturn(f) repeat with i from 1 to lng set end of lst to |λ|(item i of xs_, item i of ys_) end repeat return lst end tell end zipWith
http://rosettacode.org/wiki/Date_format
Date format
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the   current date   in the formats of:   2007-11-23     and   Friday, November 23, 2007
#Apex
Apex
  Datetime dtNow = datetime.now(); String strDt1 = dtNow.format('yyyy-MM-dd'); String strDt2 = dtNow.format('EEEE, MMMM dd, yyyy'); system.debug(strDt1); // "2007-11-10" system.debug(strDt2); //"Sunday, November 10, 2007"  
http://rosettacode.org/wiki/Damm_algorithm
Damm algorithm
The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors. The algorithm is named after H. Michael Damm. Task Verify the checksum, stored as last digit of an input.
#AutoHotkey
AutoHotkey
Damm(num){ row := 1, Damm := [[0,3,1,7,5,9,8,6,4,2] ,[7,0,9,2,1,5,4,8,6,3] ,[4,2,0,6,8,7,1,3,5,9] ,[1,7,5,0,9,8,3,4,2,6] ,[6,1,2,3,0,4,5,9,7,8] ,[3,6,7,4,2,0,9,5,8,1] ,[5,8,6,9,7,2,0,1,3,4] ,[8,9,4,5,3,6,2,0,1,7] ,[9,4,3,8,6,1,7,2,0,5] ,[2,5,8,1,4,3,6,7,9,0]] for i, v in StrSplit(SubStr(num, 1, -1)){ ++row := Damm[row, v+1] } return (SubStr(num, 0)=row-1 && !Damm[row, row]) }
http://rosettacode.org/wiki/Curzon_numbers
Curzon numbers
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1. Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1. Base here does not imply the radix of the counting system; rather the integer the equation is based on. All calculations should be done in base 10. Generalized Curzon numbers only exist for even base integers. Task Find and show the first 50 Generalized Curzon numbers for even base integers from 2 through 10. Stretch Find and show the one thousandth. See also Numbers Aplenty - Curzon numbers OEIS:A224486 - Numbers k such that 2*k+1 divides 2^k+1 (Curzon numbers) and even though it is not specifically mentioned that they are Curzon numbers: OEIS:A230076 - (A007521(n)-1)/4 (Generalized Curzon numbers with a base 4)
#Quackery
Quackery
[ number$ space 4 of swap join -5 split nip echo$ ] is rjust ( n --> )   [ 5 times [ 10 times [ behead rjust ] cr ] drop ] is display ( [ --> )   [ temp take over join temp put ] is dax ( [ --> )   [ 2dup ** 1+ unrot * 1+ mod 0 = ] is curzon ( n n --> b )   5 times [ i^ 1+ 2 * say "Curzon numbers base " dup echo cr 1 [] temp put [ 2dup curzon if dax temp share size 1000 < while 1+ again ] 2drop temp take 50 split swap display say " ... " -1 peek echo cr cr ]  
http://rosettacode.org/wiki/Curzon_numbers
Curzon numbers
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1. Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1. Base here does not imply the radix of the counting system; rather the integer the equation is based on. All calculations should be done in base 10. Generalized Curzon numbers only exist for even base integers. Task Find and show the first 50 Generalized Curzon numbers for even base integers from 2 through 10. Stretch Find and show the one thousandth. See also Numbers Aplenty - Curzon numbers OEIS:A224486 - Numbers k such that 2*k+1 divides 2^k+1 (Curzon numbers) and even though it is not specifically mentioned that they are Curzon numbers: OEIS:A230076 - (A007521(n)-1)/4 (Generalized Curzon numbers with a base 4)
#Raku
Raku
sub curzon ($base) { lazy (1..∞).hyper.map: { $_ if (exp($_, $base) + 1) %% ($base × $_ + 1) } };   for <2 4 6 8 10> { my $curzon = .&curzon; say "\nFirst 50 Curzon numbers using a base of $_:\n" ~ $curzon[^50].batch(25)».fmt("%4s").join("\n") ~ "\nOne thousandth: " ~ $curzon[999] }
http://rosettacode.org/wiki/Curzon_numbers
Curzon numbers
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1. Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1. Base here does not imply the radix of the counting system; rather the integer the equation is based on. All calculations should be done in base 10. Generalized Curzon numbers only exist for even base integers. Task Find and show the first 50 Generalized Curzon numbers for even base integers from 2 through 10. Stretch Find and show the one thousandth. See also Numbers Aplenty - Curzon numbers OEIS:A224486 - Numbers k such that 2*k+1 divides 2^k+1 (Curzon numbers) and even though it is not specifically mentioned that they are Curzon numbers: OEIS:A230076 - (A007521(n)-1)/4 (Generalized Curzon numbers with a base 4)
#Rust
Rust
// [dependencies] // rug = "1.15.0"   fn is_curzon(n: u32, k: u32) -> bool { use rug::{Complete, Integer}; (Integer::u_pow_u(k, n).complete() + 1) % (k * n + 1) == 0 }   fn main() { for k in (2..=10).step_by(2) { println!("Curzon numbers with base {k}:"); let mut count = 0; let mut n = 1; while count < 50 { if is_curzon(n, k) { count += 1; print!("{:4}{}", n, if count % 10 == 0 { "\n" } else { " " }); } n += 1; } loop { if is_curzon(n, k) { count += 1; if count == 1000 { break; } } n += 1; } println!("1000th Curzon number with base {k}: {n}\n"); } }
http://rosettacode.org/wiki/Curzon_numbers
Curzon numbers
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1. Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1. Base here does not imply the radix of the counting system; rather the integer the equation is based on. All calculations should be done in base 10. Generalized Curzon numbers only exist for even base integers. Task Find and show the first 50 Generalized Curzon numbers for even base integers from 2 through 10. Stretch Find and show the one thousandth. See also Numbers Aplenty - Curzon numbers OEIS:A224486 - Numbers k such that 2*k+1 divides 2^k+1 (Curzon numbers) and even though it is not specifically mentioned that they are Curzon numbers: OEIS:A230076 - (A007521(n)-1)/4 (Generalized Curzon numbers with a base 4)
#Sidef
Sidef
func is_curzon(n, k) { powmod(k, n, k*n + 1).is_congruent(-1, k*n + 1) && (n > 0) }   for k in (2 .. 10 `by` 2) { say "\nFirst 50 Curzon numbers using a base of #{k}:" say 50.by {|n| is_curzon(n, k) }.join(' ') say ("1000th term: ", 1000.th {|n| is_curzon(n,k) }) }
http://rosettacode.org/wiki/Cyclotomic_polynomial
Cyclotomic polynomial
The nth Cyclotomic polynomial, for any positive integer n, is the unique irreducible polynomial of largest degree with integer coefficients that is a divisor of x^n − 1, and is not a divisor of x^k − 1 for any k < n. Task Find and print the first 30 cyclotomic polynomials. Find and print the order of the first 10 cyclotomic polynomials that have n or -n as a coefficient. See also Wikipedia article, Cyclotomic polynomial, showing ways to calculate them. The sequence A013594 with the smallest order of cyclotomic polynomial containing n or -n as a coefficient.
#C.23
C#
using System; using System.Collections; using System.Collections.Generic; using System.Linq; using IntMap = System.Collections.Generic.Dictionary<int, int>;   public static class CyclotomicPolynomial { public static void Main2() { Console.WriteLine("Task 1: Cyclotomic polynomials for n <= 30:"); for (int i = 1; i <= 30; i++) { var p = GetCyclotomicPolynomial(i); Console.WriteLine($"CP[{i}] = {p.ToString()}"); } Console.WriteLine();   Console.WriteLine("Task 2: Smallest cyclotomic polynomial with n or -n as a coefficient:"); for (int i = 1, n = 0; i <= 10; i++) { while (true) { n++; var p = GetCyclotomicPolynomial(n); if (p.Any(t => Math.Abs(t.Coefficient) == i)) { Console.WriteLine($"CP[{n}] has coefficient with magnitude = {i}"); n--; break; } } } }   private const int MaxFactors = 100_000; private const int Algorithm = 2; private static readonly Term x = new Term(1, 1); private static readonly Dictionary<int, Polynomial> polyCache = new Dictionary<int, Polynomial> { [1] = x - 1 }; private static readonly Dictionary<int, IntMap> factorCache = new Dictionary<int, IntMap> { [2] = new IntMap { [2] = 1 } };   private static Polynomial GetCyclotomicPolynomial(in int n) { if (polyCache.TryGetValue(n, out var result)) return result;   var factors = GetFactors(n); if (factors.ContainsKey(n)) { //n is prime result = new Polynomial(from exp in ..n select x[exp]); } else if (factors.Count == 2 && factors.Contains(2, 1) && factors.Contains(n/2, 1)) { //n = 2p result = new Polynomial(from i in ..(n/2) select (IsOdd(i) ? -x : x)[i]); } else if (factors.Count == 1 && factors.TryGetValue(2, out int h)) { //n = 2^h result = x[1<<(h-1)] + 1; } else if (factors.Count == 1 && !factors.ContainsKey(n)) { // n = p^k (int p, int k) = factors.First(); result = new Polynomial(from i in ..p select x[i * (int)Math.Pow(p, k-1)]); } else if (factors.Count == 2 && factors.ContainsKey(2)) { //n = 2^h * p^k (int p, int k) = factors.First(entry => entry.Key != 2); int twoExp = 1 << (factors[2] - 1); result = new Polynomial(from i in ..p select (IsOdd(i) ? -x : x)[i * twoExp * (int)Math.Pow(p, k-1)]); } else if (factors.ContainsKey(2) && IsOdd(n/2) && n/2 > 1) { // CP(2m)[x] = CP[-m][x], n is odd > 1 Polynomial cycloDiv2 = GetCyclotomicPolynomial(n/2); result = new Polynomial(from term in cycloDiv2 select IsOdd(term.Exponent) ? -term : term); #pragma warning disable CS0162 } else if (Algorithm == 0) { var divisors = GetDivisors(n); result = x[n] - 1; foreach (int d in divisors) result /= GetCyclotomicPolynomial(d); } else if (Algorithm == 1) { var divisors = GetDivisors(n).ToList(); int maxDivisor = divisors.Max(); result = (x[n] - 1) / (x[maxDivisor] - 1); foreach (int d in divisors.Where(div => maxDivisor % div == 0)) { result /= GetCyclotomicPolynomial(d); } } else if (Algorithm == 2) { int m = 1; result = GetCyclotomicPolynomial(m); var primes = factors.Keys.ToList(); primes.Sort(); foreach (int prime in primes) { var cycloM = result; result = new Polynomial(from term in cycloM select term.Coefficient * x[term.Exponent * prime]); result /= cycloM; m *= prime; } int s = n / m; result = new Polynomial(from term in result select term.Coefficient * x[term.Exponent * s]); #pragma warning restore CS0162 } else { throw new InvalidOperationException("Invalid algorithm"); } polyCache[n] = result; return result; }   private static bool IsOdd(int i) => (i & 1) != 0; private static bool Contains(this IntMap map, int key, int value) => map.TryGetValue(key, out int v) && v == value; private static int GetOrZero(this IntMap map, int key) => map.TryGetValue(key, out int v) ? v : 0; private static IEnumerable<T> Select<T>(this Range r, Func<int, T> f) => Enumerable.Range(r.Start.Value, r.End.Value - r.Start.Value).Select(f);   private static IntMap GetFactors(in int n) { if (factorCache.TryGetValue(n, out var factors)) return factors;   factors = new IntMap(); if (!IsOdd(n)) { foreach (var entry in GetFactors(n/2)) factors.Add(entry.Key, entry.Value); factors[2] = factors.GetOrZero(2) + 1; return Cache(n, factors); } for (int i = 3; i * i <= n; i+=2) { if (n % i == 0) { foreach (var entry in GetFactors(n/i)) factors.Add(entry.Key, entry.Value); factors[i] = factors.GetOrZero(i) + 1; return Cache(n, factors); } } factors[n] = 1; return Cache(n, factors); }   private static IntMap Cache(int n, IntMap factors) { if (n < MaxFactors) factorCache[n] = factors; return factors; }   private static IEnumerable<int> GetDivisors(int n) { for (int i = 1; i * i <= n; i++) { if (n % i == 0) { yield return i; int div = n / i; if (div != i && div != n) yield return div; } } }   public sealed class Polynomial : IEnumerable<Term> { public Polynomial() { } public Polynomial(params Term[] terms) : this(terms.AsEnumerable()) { }   public Polynomial(IEnumerable<Term> terms) { Terms.AddRange(terms); Simplify(); }   private List<Term>? terms; private List<Term> Terms => terms ??= new List<Term>();   public int Count => terms?.Count ?? 0; public int Degree => Count == 0 ? -1 : Terms[0].Exponent; public int LeadingCoefficient => Count == 0 ? 0 : Terms[0].Coefficient;   public IEnumerator<Term> GetEnumerator() => Terms.GetEnumerator(); IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();   public override string ToString() => Count == 0 ? "0" : string.Join(" + ", Terms).Replace("+ -", "- ");   public static Polynomial operator *(Polynomial p, Term t) => new Polynomial(from s in p select s * t); public static Polynomial operator +(Polynomial p, Polynomial q) => new Polynomial(p.Terms.Concat(q.Terms)); public static Polynomial operator -(Polynomial p, Polynomial q) => new Polynomial(p.Terms.Concat(q.Terms.Select(t => -t))); public static Polynomial operator *(Polynomial p, Polynomial q) => new Polynomial(from s in p from t in q select s * t); public static Polynomial operator /(Polynomial p, Polynomial q) => p.Divide(q).quotient;   public (Polynomial quotient, Polynomial remainder) Divide(Polynomial divisor) { if (Degree < 0) return (new Polynomial(), this); Polynomial quotient = new Polynomial(); Polynomial remainder = this; int lcv = divisor.LeadingCoefficient; int dv = divisor.Degree; while (remainder.Degree >= divisor.Degree) { int lcr = remainder.LeadingCoefficient; Term div = new Term(lcr / lcv, remainder.Degree - dv); quotient.Terms.Add(div); remainder += divisor * -div; } quotient.Simplify(); remainder.Simplify(); return (quotient, remainder); }   private void Simplify() { if (Count < 2) return; Terms.Sort((a, b) => -a.CompareTo(b)); for (int i = Terms.Count - 1; i > 0; i--) { Term s = Terms[i-1]; Term t = Terms[i]; if (t.Exponent == s.Exponent) { Terms[i-1] = new Term(s.Coefficient + t.Coefficient, s.Exponent); Terms.RemoveAt(i); } } Terms.RemoveAll(t => t.IsZero); }   }   public readonly struct Term : IEquatable<Term>, IComparable<Term> { public Term(int coefficient, int exponent = 0) => (Coefficient, Exponent) = (coefficient, exponent);   public Term this[int exponent] => new Term(Coefficient, exponent); //Using x[exp] because x^exp has low precedence public int Coefficient { get; } public int Exponent { get; } public bool IsZero => Coefficient == 0;   public static Polynomial operator +(Term left, Term right) => new Polynomial(left, right); public static Polynomial operator -(Term left, Term right) => new Polynomial(left, -right); public static implicit operator Term(int coefficient) => new Term(coefficient); public static Term operator -(Term t) => new Term(-t.Coefficient, t.Exponent); public static Term operator *(Term left, Term right) => new Term(left.Coefficient * right.Coefficient, left.Exponent + right.Exponent);   public static bool operator ==(Term left, Term right) => left.Equals(right); public static bool operator !=(Term left, Term right) => !left.Equals(right); public static bool operator <(Term left, Term right) => left.CompareTo(right) < 0; public static bool operator >(Term left, Term right) => left.CompareTo(right) > 0; public static bool operator <=(Term left, Term right) => left.CompareTo(right) <= 0; public static bool operator >=(Term left, Term right) => left.CompareTo(right) >= 0;   public bool Equals(Term other) => Exponent == other.Exponent && Coefficient == other.Coefficient; public override bool Equals(object? obj) => obj is Term t && Equals(t); public override int GetHashCode() => Coefficient.GetHashCode() * 31 + Exponent.GetHashCode();   public int CompareTo(Term other) { int c = Exponent.CompareTo(other.Exponent); if (c != 0) return c; return Coefficient.CompareTo(other.Coefficient); }   public override string ToString() => (Coefficient, Exponent) switch { (0, _) => "0", (_, 0) => $"{Coefficient}", (1, 1) => "x", (-1, 1) => "-x", (_, 1) => $"{Coefficient}x", (1, _) => $"x^{Exponent}", (-1, _) => $"-x^{Exponent}", _ => $"{Coefficient}x^{Exponent}" }; } }
http://rosettacode.org/wiki/Cut_a_rectangle
Cut a rectangle
A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such paths for 2 × 2 and 4 × 3 rectangles are shown below. Write a program that calculates the number of different ways to cut an m × n rectangle. Optionally, show each of the cuts. Possibly related task: Maze generation for depth-first search.
#Go
Go
package main   import "fmt"   var grid []byte var w, h, last int var cnt int var next [4]int var dir = [4][2]int{{0, -1}, {-1, 0}, {0, 1}, {1, 0}}   func walk(y, x int) { if y == 0 || y == h || x == 0 || x == w { cnt += 2 return } t := y*(w+1) + x grid[t]++ grid[last-t]++ for i, d := range dir { if grid[t+next[i]] == 0 { walk(y+d[0], x+d[1]) } } grid[t]-- grid[last-t]-- }   func solve(hh, ww, recur int) int { h = hh w = ww   if h&1 != 0 { h, w = w, h } switch { case h&1 == 1: return 0 case w == 1: return 1 case w == 2: return h case h == 2: return w } cy := h / 2 cx := w / 2   grid = make([]byte, (h+1)*(w+1)) last = len(grid) - 1 next[0] = -1 next[1] = -w - 1 next[2] = 1 next[3] = w + 1   if recur != 0 { cnt = 0 } for x := cx + 1; x < w; x++ { t := cy*(w+1) + x grid[t] = 1 grid[last-t] = 1 walk(cy-1, x) } cnt++   if h == w { cnt *= 2 } else if w&1 == 0 && recur != 0 { solve(w, h, 0) } return cnt }   func main() { for y := 1; y <= 10; y++ { for x := 1; x <= y; x++ { if x&1 == 0 || y&1 == 0 { fmt.Printf("%d x %d: %d\n", y, x, solve(y, x, 1)) } } } }
http://rosettacode.org/wiki/Cyclops_numbers
Cyclops numbers
A cyclops number is a number with an odd number of digits that has a zero in the center, but nowhere else. They are named so in tribute to the one eyed giants Cyclops from Greek mythology. Cyclops numbers can be found in any base. This task strictly is looking for cyclops numbers in base 10. There are many different classifications of cyclops numbers with minor differences in characteristics. In an effort to head off a whole series of tasks with tiny variations, we will cover several variants here. Task Find and display here on this page the first 50 cyclops numbers in base 10 (all of the sub tasks are restricted to base 10). Find and display here on this page the first 50 prime cyclops numbers. (cyclops numbers that are prime.) Find and display here on this page the first 50 blind prime cyclops numbers. (prime cyclops numbers that remain prime when "blinded"; the zero is removed from the center.) Find and display here on this page the first 50 palindromic prime cyclops numbers. (prime cyclops numbers that are palindromes.) Stretch Find and display the first cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first blind prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first palindromic prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. (Note: there are no cyclops numbers between ten million and one hundred million, they need to have an odd number of digits) See also OEIS A134808 - Cyclops numbers OEIS A134809 - Cyclops primes OEIS A329737 - Cyclops primes that remain prime after being "blinded" OEIS A136098 - Prime palindromic cyclops numbers
#REXX
REXX
/*REXX pgm finds 1st N cyclops (Θ) #s, Θ primes, blind Θ primes, palindromic Θ primes*/ parse arg n cols . /*obtain optional argument from the CL.*/ if n=='' | n=="," then n= 50 /*Not specified? Then use the default.*/ if cols=='' | cols=="," then cols= 10 /* " " " " " " */ call genP /*build array of semaphores for primes.*/ w= max(10, length( commas(@.#) ) ) /*max width of a number in any column. */ pri?= 0; bli?= 0; pal?= 0; call 0 ' first ' commas(n) " cyclops numbers" pri?= 1; bli?= 0; pal?= 0; call 0 ' first ' commas(n) " prime cyclops numbers" pri?= 1; bli?= 1; pal?= 0; call 0 ' first ' commas(n) " blind prime cyclops numbers" pri?= 1; bli?= 0; pal?= 1; call 0 ' first ' commas(n) " palindromic prime cyclops numbers" exit 0 /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ commas: parse arg ?; do jc=length(?)-3 to 1 by -3; ?=insert(',', ?, jc); end; return ? /*──────────────────────────────────────────────────────────────────────────────────────*/ 0: parse arg title; idx= 1 /*get the title of this output section.*/ say ' index │'center(title, 1 + cols*(w+1) ) /*display the output title. */ say '───────┼'center("" , 1 + cols*(w+1), '─') /* " " " separator*/ finds= 0; $= /*the number of finds (so far); $ list.*/ do j=0 until finds== n; L= length(j) /*find N cyclops numbers, start at 101.*/ if L//2==0 then do; j= left(1, L+1, 0) /*Is J an even # of digits? Yes, bump J*/ iterate /*use a new J that has odd # of digits.*/ end z= pos(0, j); if z\==(L+1)%2 then iterate /* " " " " (zero in mid)? " */ if pos(0, j, z+1)>0 then iterate /* " " " " (has two 0's)? " */ if pri? then if \!.j then iterate /*Need a cyclops prime? Then skip.*/ if bli? then do;  ?= space(translate(j, , 0), 0) /*Need a blind cyclops prime ?*/ if \!.? then iterate /*Not a blind cyclops prime? Then skip.*/ end if pal? then do; r= reverse(j) /*Need a palindromic cyclops prime? */ if r\==j then iterate /*Cyclops number not palindromic? Skip.*/ if \!.r then iterate /* " palindrome not prime? " */ end finds= finds + 1 /*bump the number of palindromic primes*/ $= $ right( commas(j), w) /*add a palindromic prime ──► $ list.*/ if finds//cols\==0 then iterate /*have we populated a line of output? */ say center(idx, 7)'│' substr($, 2); $= /*display what we have so far (cols). */ idx= idx + cols /*bump the index count for the output*/ end /*j*/ if $\=='' then say center(idx, 7)"│" substr($, 2) /*possible show residual output.*/ say '───────┴'center("" , 1 + cols*(w+1), '─'); say return /*──────────────────────────────────────────────────────────────────────────────────────*/ genP: !.= 0; hip= 7890987 - 1 /*placeholders for primes (semaphores).*/ @.1=2; @.2=3; @.3=5; @.4=7; @.5=11; @.6=13 /*define some low primes. */  !.2=1; !.3=1; !.5=1; !.7=1; !.11=1; !.13=1 /* " " " " flags. */ #= 6; sq.#= @.# ** 2 /*number of primes so far; prime square*/ do j=@.#+2 by 2 for max(0, hip%2-@.#%2-1) /*find odd primes from here on. */ parse var j '' -1 _ /*get the last dec. digit of J.*/ if _==5 then iterate; if j// 3==0 then iterate /*÷ by 5? ÷ by 3? Skip.*/ if j// 7==0 then iterate; if j//11==0 then iterate /*÷ " 7? ÷ by 11? " */ do k=6 while sq.k<=j /* [↓] divide by the known odd primes.*/ if j // @.k == 0 then iterate j /*Is J ÷ X? Then not prime. ___ */ end /*k*/ /* [↑] only process numbers ≤ √ J */ #= #+1; @.#= j; sq.#= j*j;  !.j= 1 /*bump # Ps; assign next P; P sq; P# */ end /*j*/; return
http://rosettacode.org/wiki/Date_manipulation
Date manipulation
Task Given the date string "March 7 2009 7:30pm EST", output the time 12 hours later in any human-readable format. As extra credit, display the resulting time in a time zone different from your own.
#Clojure
Clojure
(import java.util.Date java.text.SimpleDateFormat)   (defn time+12 [s] (let [sdf (SimpleDateFormat. "MMMM d yyyy h:mma zzz")] (-> (.parse sdf s) (.getTime ,) (+ , 43200000) long (Date. ,) (->> , (.format sdf ,)))))
http://rosettacode.org/wiki/Date_manipulation
Date manipulation
Task Given the date string "March 7 2009 7:30pm EST", output the time 12 hours later in any human-readable format. As extra credit, display the resulting time in a time zone different from your own.
#COBOL
COBOL
identification division. program-id. date-manipulation.   environment division. configuration section. repository. function all intrinsic.   data division. working-storage section. 01 given-date. 05 filler value z"March 7 2009 7:30pm EST". 01 date-spec. 05 filler value z"%B %d %Y %I:%M%p %Z".   01 time-struct. 05 tm-sec usage binary-long. 05 tm-min usage binary-long. 05 tm-hour usage binary-long. 05 tm-mday usage binary-long. 05 tm-mon usage binary-long. 05 tm-year usage binary-long. 05 tm-wday usage binary-long. 05 tm-yday usage binary-long. 05 tm-isdst usage binary-long. 05 tm-gmtoff usage binary-c-long. 05 tm-zone usage pointer. 01 scan-index usage pointer.   01 time-t usage binary-c-long. 01 time-tm usage pointer.   01 reform-buffer pic x(64). 01 reform-length usage binary-long.   01 current-locale usage pointer.   01 iso-spec constant as "YYYY-MM-DDThh:mm:ss+hh:mm". 01 iso-date constant as "2009-03-07T19:30:00-05:00". 01 date-integer pic 9(9). 01 time-integer pic 9(9).   procedure division.   call "strptime" using by reference given-date by reference date-spec by reference time-struct returning scan-index on exception display "error calling strptime" upon syserr end-call display "Given: " given-date   if scan-index not equal null then *> add 12 hours, and reform as local call "mktime" using time-struct returning time-t add 43200 to time-t perform form-datetime   *> reformat as Pacific time set environment "TZ" to "PST8PDT" call "tzset" returning omitted perform form-datetime   *> reformat as Greenwich mean set environment "TZ" to "GMT" call "tzset" returning omitted perform form-datetime     *> reformat for Tokyo time, as seen in Hong Kong set environment "TZ" to "Japan" call "tzset" returning omitted call "setlocale" using by value 6 by content z"en_HK.utf8" returning current-locale on exception display "error with setlocale" upon syserr end-call move z"%c" to date-spec perform form-datetime else display "date parse error" upon syserr end-if   *> A more standard COBOL approach, based on ISO8601 display "Given: " iso-date move integer-of-formatted-date(iso-spec, iso-date) to date-integer   move seconds-from-formatted-time(iso-spec, iso-date) to time-integer   add 43200 to time-integer if time-integer greater than 86400 then subtract 86400 from time-integer add 1 to date-integer end-if display " " substitute(formatted-datetime(iso-spec date-integer, time-integer, -300), "T", "/")   goback.   form-datetime. call "localtime" using time-t returning time-tm call "strftime" using by reference reform-buffer by value length(reform-buffer) by reference date-spec by value time-tm returning reform-length on exception display "error calling strftime" upon syserr end-call if reform-length > 0 and <= length(reform-buffer) then display " " reform-buffer(1 : reform-length) else display "date format error" upon syserr end-if . end program date-manipulation.  
http://rosettacode.org/wiki/Deal_cards_for_FreeCell
Deal cards for FreeCell
Free Cell is the solitaire card game that Paul Alfille introduced to the PLATO system in 1978. Jim Horne, at Microsoft, changed the name to FreeCell and reimplemented the game for DOS, then Windows. This version introduced 32000 numbered deals. (The FreeCell FAQ tells this history.) As the game became popular, Jim Horne disclosed the algorithm, and other implementations of FreeCell began to reproduce the Microsoft deals. These deals are numbered from 1 to 32000. Newer versions from Microsoft have 1 million deals, numbered from 1 to 1000000; some implementations allow numbers outside that range. The algorithm uses this linear congruential generator from Microsoft C: s t a t e n + 1 ≡ 214013 × s t a t e n + 2531011 ( mod 2 31 ) {\displaystyle state_{n+1}\equiv 214013\times state_{n}+2531011{\pmod {2^{31}}}} r a n d n = s t a t e n ÷ 2 16 {\displaystyle rand_{n}=state_{n}\div 2^{16}} r a n d n {\displaystyle rand_{n}} is in range 0 to 32767. Rosetta Code has another task, linear congruential generator, with code for this RNG in several languages. The algorithm follows: Seed the RNG with the number of the deal. Create an array of 52 cards: Ace of Clubs, Ace of Diamonds, Ace of Hearts, Ace of Spades, 2 of Clubs, 2 of Diamonds, and so on through the ranks: Ace, 2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen, King. The array indexes are 0 to 51, with Ace of Clubs at 0, and King of Spades at 51. Until the array is empty: Choose a random card at index ≡ next random number (mod array length). Swap this random card with the last card of the array. Remove this random card from the array. (Array length goes down by 1.) Deal this random card. Deal all 52 cards, face up, across 8 columns. The first 8 cards go in 8 columns, the next 8 cards go on the first 8 cards, and so on. Order to deal cards Game #1 Game #617 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 JD 2D 9H JC 5D 7H 7C 5H KD KC 9S 5S AD QC KH 3H 2S KS 9D QD JS AS AH 3C 4C 5C TS QH 4H AC 4D 7S 3S TD 4S TH 8H 2C JH 7D 6D 8S 8D QS 6C 3D 8C TC 6S 9C 2H 6H 7D AD 5C 3S 5S 8C 2D AH TD 7S QD AC 6D 8H AS KH TH QC 3H 9D 6S 8D 3D TC KD 5H 9S 3C 8S 7H 4D JS 4C QS 9C 9H 7C 6H 2C 2S 4S TS 2H 5D JC 6C JH QH JD KS KC 4H Deals can also be checked against FreeCell solutions to 1000000 games. (Summon a video solution, and it displays the initial deal.) Write a program to take a deal number and deal cards in the same order as this algorithm. The program may display the cards with ASCII, with Unicode, by drawing graphics, or any other way. Related tasks: Playing cards Card shuffles War Card_Game Poker hand_analyser Go Fish
#PARI.2FGP
PARI/GP
card(n)=concat(["A","2","3","4","5","6","7","8","9","T","J","Q","K"][n\4+1],["C","D","H","S"][n%4+1]); nextrand()={ (state=(214013*state+2531011)%2^31)>>16 }; deal(seed)={ my(deck=vector(52,n,n-1),t); local(state=seed); forstep(last=52,1,-1, t=nextrand()%last+1; print1(card(deck[t]),if(last%8==5,"\n"," ")); deck[t]=deck[last] ) };
http://rosettacode.org/wiki/Define_a_primitive_data_type
Define a primitive data type
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
#Swift
Swift
struct SmallInt { var value: Int   init(value: Int) { guard value >= 1 && value <= 10 else { fatalError("SmallInts must be in the range [1, 10]") }   self.value = value }   static func +(_ lhs: SmallInt, _ rhs: SmallInt) -> SmallInt { SmallInt(value: lhs.value + rhs.value) } static func -(_ lhs: SmallInt, _ rhs: SmallInt) -> SmallInt { SmallInt(value: lhs.value - rhs.value) } static func *(_ lhs: SmallInt, _ rhs: SmallInt) -> SmallInt { SmallInt(value: lhs.value * rhs.value) } static func /(_ lhs: SmallInt, _ rhs: SmallInt) -> SmallInt { SmallInt(value: lhs.value / rhs.value) } }   extension SmallInt: ExpressibleByIntegerLiteral { public init(integerLiteral value: Int) { self.init(value: value) } }   extension SmallInt: CustomStringConvertible { public var description: String { "\(value)" } }   let a: SmallInt = 1 let b: SmallInt = 9 let c: SmallInt = 10 let d: SmallInt = 2   print(a + b) print(c - b) print(a * c) print(c / d) print(a + c)
http://rosettacode.org/wiki/Define_a_primitive_data_type
Define a primitive data type
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
#Tcl
Tcl
namespace eval ::myIntType { variable value_cache array set value_cache {} variable type integer variable min 1 variable max 10 variable errMsg "cannot set %s to %s: must be a $type between $min and $max" } proc ::myIntType::declare varname { set ns [namespace current] uplevel [list trace add variable $varname write ${ns}::write] uplevel [list trace add variable $varname unset ${ns}::unset_var] } proc ::myIntType::unset_var {varname args} { variable value_cache unset value_cache($varname) } proc ::myIntType::validate {value} { variable type variable min variable max expr {[string is $type -strict $value] && $min <= $value && $value <= $max} } proc ::myIntType::write {varname args} { variable value_cache upvar $varname var set value $var if {[validate $value]} { set value_cache($varname) $value } else { if {[info exists value_cache($varname)]} { set var $value_cache($varname) } variable errMsg error [format $errMsg $varname $value] } }
http://rosettacode.org/wiki/Day_of_the_week
Day of the week
A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January). Task In what years between 2008 and 2121 will the 25th of December be a Sunday? Using any standard date handling libraries of your programming language; compare the dates calculated with the output of other languages to discover any anomalies in the handling of dates which may be due to, for example, overflow in types used to represent dates/times similar to   y2k   type problems.
#C.2B.2B
C++
#include <boost/date_time/gregorian/gregorian.hpp> #include <iostream>   int main( ) { using namespace boost::gregorian ;   std::cout << "Yuletide holidays must be allowed in the following years:\n" ; for ( int i = 2008 ; i < 2121 ; i++ ) { greg_year gy = i ; date d ( gy, Dec , 25 ) ; if ( d.day_of_week( ) == Sunday ) { std::cout << i << std::endl ; } } std::cout << "\n" ; return 0 ; }
http://rosettacode.org/wiki/CUSIP
CUSIP
This page uses content from Wikipedia. The original article was at CUSIP. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) A   CUSIP   is a nine-character alphanumeric code that identifies a North American financial security for the purposes of facilitating clearing and settlement of trades. The CUSIP was adopted as an American National Standard under Accredited Standards X9.6. Task Ensure the last digit   (i.e., the   check digit)   of the CUSIP code (the 1st column) is correct, against the following:   037833100       Apple Incorporated   17275R102       Cisco Systems   38259P508       Google Incorporated   594918104       Microsoft Corporation   68389X106       Oracle Corporation   (incorrect)   68389X105       Oracle Corporation Example pseudo-code below. algorithm Cusip-Check-Digit(cusip) is Input: an 8-character CUSIP   sum := 0 for 1 ≤ i ≤ 8 do c := the ith character of cusip if c is a digit then v := numeric value of the digit c else if c is a letter then p := ordinal position of c in the alphabet (A=1, B=2...) v := p + 9 else if c = "*" then v := 36 else if c = "@" then v := 37 else if' c = "#" then v := 38 end if if i is even then v := v × 2 end if   sum := sum + int ( v div 10 ) + v mod 10 repeat   return (10 - (sum mod 10)) mod 10 end function See related tasks SEDOL ISIN
#Arturo
Arturo
validCUSIP?: function [cusip][ s: 0 alpha: `A`..`Z`   loop.with:'i chop cusip 'c [ v: 0   case ø when? [numeric? c] -> v: to :integer to :string c when? [in? c alpha] -> v: (index alpha c) + 1 + 9 when? [c = `*`] -> v: 36 when? [c = `@`] -> v: 37 when? [c = `#`] -> v: 38 else []   if odd? i -> v: 2 * v   s: s + (v / 10) + (v % 10) ] check: (10 - (s % 10)) % 10   return check = to :integer to :string last cusip ]   loop ["037833100" "17275R102" "38259P508" "594918104" "68389X106" "68389X105"] 'cusip [ print [cusip "=>" (validCUSIP? cusip)? -> "VALID" -> "INVALID"] ]
http://rosettacode.org/wiki/Date_format
Date format
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the   current date   in the formats of:   2007-11-23     and   Friday, November 23, 2007
#AppleScript
AppleScript
set {year:y, month:m, day:d, weekday:w} to (current date)   tell (y * 10000 + m * 100 + d) as text to set shortFormat to text 1 thru 4 & "-" & text 5 thru 6 & "-" & text 7 thru 8 set longFormat to (w as text) & (", " & m) & (space & d) & (", " & y)   return (shortFormat & linefeed & longFormat)
http://rosettacode.org/wiki/Damm_algorithm
Damm algorithm
The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors. The algorithm is named after H. Michael Damm. Task Verify the checksum, stored as last digit of an input.
#AWK
AWK
# syntax: GAWK -f DAMM_ALGORITHM.AWK BEGIN { damm_init() leng = split("5724,5727,112946",arr,",") # test cases for (i=1; i<=leng; i++) { n = arr[i] printf("%s %s\n",damm_check(n),n) } exit(0) } function damm_check(n, a,i) { a = 0 for (i=1; i<=length(n); i++) { a = substr(damm[a],substr(n,i,1)+1,1) } return(a == 0 ? "T" : "F") } function damm_init() { # 0123456789 damm[0] = "0317598642" damm[1] = "7092154863" damm[2] = "4206871359" damm[3] = "1750983426" damm[4] = "6123045978" damm[5] = "3674209581" damm[6] = "5869720134" damm[7] = "8945362017" damm[8] = "9438617205" damm[9] = "2581436790" }
http://rosettacode.org/wiki/Curzon_numbers
Curzon numbers
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1. Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1. Base here does not imply the radix of the counting system; rather the integer the equation is based on. All calculations should be done in base 10. Generalized Curzon numbers only exist for even base integers. Task Find and show the first 50 Generalized Curzon numbers for even base integers from 2 through 10. Stretch Find and show the one thousandth. See also Numbers Aplenty - Curzon numbers OEIS:A224486 - Numbers k such that 2*k+1 divides 2^k+1 (Curzon numbers) and even though it is not specifically mentioned that they are Curzon numbers: OEIS:A230076 - (A007521(n)-1)/4 (Generalized Curzon numbers with a base 4)
#Vlang
Vlang
import math.big   fn main() { zero := big.zero_int one := big.one_int for k := i64(2); k <= 10; k += 2 { bk := big.integer_from_i64(k) println("The first 50 Curzon numbers using a base of $k:") mut count := 0 mut n := i64(1) mut pow := big.integer_from_i64(k) mut curzon50 := []i64{} for { z := pow + one d := k*n + 1 bd := big.integer_from_i64(d) if z%bd == zero { if count < 50 { curzon50 << n } count++ if count == 50 { for i in 0..curzon50.len { print("${curzon50[i]:4} ") if (i+1)%10 == 0 { println('') } } print("\nOne thousandth: ") } if count == 1000 { println(n) break } } n++ pow *= bk } println('') } }
http://rosettacode.org/wiki/Curzon_numbers
Curzon numbers
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1. Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1. Base here does not imply the radix of the counting system; rather the integer the equation is based on. All calculations should be done in base 10. Generalized Curzon numbers only exist for even base integers. Task Find and show the first 50 Generalized Curzon numbers for even base integers from 2 through 10. Stretch Find and show the one thousandth. See also Numbers Aplenty - Curzon numbers OEIS:A224486 - Numbers k such that 2*k+1 divides 2^k+1 (Curzon numbers) and even though it is not specifically mentioned that they are Curzon numbers: OEIS:A230076 - (A007521(n)-1)/4 (Generalized Curzon numbers with a base 4)
#Wren
Wren
/* curzon_numbers.wren */   import "./gmp" for Mpz import "./seq" for Lst import "./fmt" for Fmt   for (k in [2, 4, 6, 8, 10]) { System.print("The first 50 Curzon numbers using a base of %(k):") var count = 0 var n = 1 var pow = Mpz.from(k) var curzon50 = [] while (true) { var z = pow + Mpz.one var d = k*n + 1 if (z.isDivisibleUi(d)) { if (count < 50) curzon50.add(n) count = count + 1 if (count == 50) { for (chunk in Lst.chunks(curzon50, 10)) Fmt.print("$4d", chunk) System.write("\nOne thousandth: ") } if (count == 1000) { System.print(n) break } } n = n + 1 pow.mul(k) } System.print() }
http://rosettacode.org/wiki/Cyclotomic_polynomial
Cyclotomic polynomial
The nth Cyclotomic polynomial, for any positive integer n, is the unique irreducible polynomial of largest degree with integer coefficients that is a divisor of x^n − 1, and is not a divisor of x^k − 1 for any k < n. Task Find and print the first 30 cyclotomic polynomials. Find and print the order of the first 10 cyclotomic polynomials that have n or -n as a coefficient. See also Wikipedia article, Cyclotomic polynomial, showing ways to calculate them. The sequence A013594 with the smallest order of cyclotomic polynomial containing n or -n as a coefficient.
#D
D
import std.algorithm; import std.exception; import std.format; import std.functional; import std.math; import std.range; import std.stdio;   immutable MAX_ALL_FACTORS = 100_000; immutable ALGORITHM = 2;   //Note: Cyclotomic Polynomials have small coefficients. Not appropriate for general polynomial usage.   struct Term { private long m_coefficient; private long m_exponent;   public this(long c, long e) { m_coefficient = c; m_exponent = e; }   public long coefficient() const { return m_coefficient; }   public long exponent() const { return m_exponent; }   public Term opUnary(string op)() const { static if (op == "-") { return Term(-m_coefficient, m_exponent); } else { assert(false, "Not implemented"); } }   public Term opBinary(string op)(Term term) const { static if (op == "+") { if (exponent() != term.exponent()) { assert(false, "Error 102: Exponents not equals."); } return Term(coefficient() + term.coefficient(), exponent()); } else if (op == "*") { return Term(coefficient() * term.coefficient(), exponent() + term.exponent()); } else { assert(false, "Not implemented: " ~ op); } }   public void toString(scope void delegate(const(char)[]) sink) const { auto spec = singleSpec("%s"); if (m_coefficient == 0) { sink("0"); } else if (m_exponent == 0) { formatValue(sink, m_coefficient, spec); } else if (m_coefficient == 1) { if (m_exponent == 1) { sink("x"); } else { sink("x^"); formatValue(sink, m_exponent, spec); } } else if (m_coefficient == -1) { if (m_exponent == 1) { sink("-x"); } else { sink("-x^"); formatValue(sink, m_exponent, spec); } } else if (m_exponent == 1) { formatValue(sink, m_coefficient, spec); sink("x"); } else { formatValue(sink, m_coefficient, spec); sink("x^"); formatValue(sink, m_exponent, spec); } } }   struct Polynomial { private Term[] terms;   public this(const Term[] ts...) { terms = ts.dup; terms.sort!"b.exponent < a.exponent"; }   bool hasCoefficientAbs(int coeff) const { foreach (term; terms) { if (abs(term.coefficient) == coeff) { return true; } } return false; }   public long leadingCoefficient() const { return terms[0].coefficient(); }   public long degree() const { if (terms.empty) { return -1; } return terms[0].exponent(); }   public Polynomial opBinary(string op)(Term term) const { static if (op == "+") { Term[] newTerms; auto added = false; foreach (currentTerm; terms) { if (currentTerm.exponent() == term.exponent()) { added = true; if (currentTerm.coefficient() + term.coefficient() != 0) { newTerms ~= currentTerm + term; } } else { newTerms ~= currentTerm; } } if (!added) { newTerms ~= term; } return Polynomial(newTerms); } else if (op == "*") { Term[] newTerms; foreach (currentTerm; terms) { newTerms ~= currentTerm * term; } return Polynomial(newTerms); } else { assert(false, "Not implemented: " ~ op); } }   public Polynomial opBinary(string op)(Polynomial rhs) const { static if (op == "+") { Term[] newTerms; auto thisCount = terms.length; auto polyCount = rhs.terms.length; while (thisCount > 0 || polyCount > 0) { if (thisCount == 0) { newTerms ~= rhs.terms[polyCount - 1]; polyCount--; } else if (polyCount == 0) { newTerms ~= terms[thisCount - 1]; thisCount--; } else { auto thisTerm = terms[thisCount - 1]; auto polyTerm = rhs.terms[polyCount - 1]; if (thisTerm.exponent() == polyTerm.exponent()) { auto t = thisTerm + polyTerm; if (t.coefficient() != 0) { newTerms ~= t; } thisCount--; polyCount--; } else if (thisTerm.exponent() < polyTerm.exponent()) { newTerms ~= thisTerm; thisCount--; } else { newTerms ~= polyTerm; polyCount--; } } } return Polynomial(newTerms); } else if (op == "/") { Polynomial q; auto r = Polynomial(terms); auto lcv = rhs.leadingCoefficient(); auto dv = rhs.degree(); while (r.degree() >= rhs.degree()) { auto lcr = r.leadingCoefficient(); auto s = lcr / lcv; auto term = Term(s, r.degree() - dv); q = q + term; r = r + rhs * -term; } return q; } else { assert(false, "Not implemented: " ~ op); } }   public int opApply(int delegate(Term) dg) const { foreach (term; terms) { auto rv = dg(term); if (rv != 0) { return rv; } } return 0; }   public void toString(scope void delegate(const(char)[]) sink) const { auto spec = singleSpec("%s"); if (!terms.empty) { formatValue(sink, terms[0], spec); foreach (t; terms[1..$]) { if (t.coefficient > 0) { sink(" + "); formatValue(sink, t, spec); } else { sink(" - "); formatValue(sink, -t, spec); } } } } }   void putAll(K, V)(ref V[K] a, V[K] b) { foreach (k, v; b) { a[k] = v; } }   void merge(K, V, F)(ref V[K] a, K k, V v, F f) { if (k in a) { a[k] = f(a[k], v); } else { a[k] = v; } }   int sum(int a, int b) { return a + b; }   int[int] getFactorsImpl(int number) { int[int] factors; if (number % 2 == 0) { if (number > 2) { auto factorsDivTwo = memoize!getFactorsImpl(number / 2); factors.putAll(factorsDivTwo); } factors.merge(2, 1, &sum); return factors; } auto root = sqrt(cast(real) number); auto i = 3; while (i <= root) { if (number % i == 0) { factors.putAll(memoize!getFactorsImpl(number / i)); factors.merge(i, 1, &sum); return factors; } i += 2; } factors[number] = 1; return factors; } alias getFactors = memoize!getFactorsImpl;   int[] getDivisors(int number) { int[] divisors; auto root = cast(int)sqrt(cast(real) number); foreach (i; 1..root) { if (number % i == 0) { divisors ~= i; } auto div = number / i; if (div != i && div != number) { divisors ~= div; } } return divisors; }   Polynomial cyclotomicPolynomialImpl(int n) { if (n == 1) { // Polynomial: x - 1 return Polynomial(Term(1, 1), Term(-1, 0)); } auto factors = getFactors(n); if (n in factors) { // n prime Term[] terms; foreach (i; 0..n) { terms ~= Term(1, i); } return Polynomial(terms); } else if (factors.length == 2 && 2 in factors && factors[2] == 1 && (n / 2) in factors && factors[n / 2] == 1) { // n = 2p auto prime = n / 2; Term[] terms; auto coeff = -1; foreach (i; 0..prime) { coeff *= -1; terms ~= Term(coeff, i); } return Polynomial(terms); } else if (factors.length == 1 && 2 in factors) { // n = 2^h auto h = factors[2]; Term[] terms; terms ~= Term(1, 2 ^^ (h - 1)); terms ~= Term(1, 0); return Polynomial(terms); } else if (factors.length == 1 && n !in factors) { // n = p^k auto p = 0; auto k = 0; foreach (prime, v; factors) { if (prime > p) { p = prime; k = v; } } Term[] terms; foreach (i; 0..p) { terms ~= Term(1, (i * p) ^^ (k - 1)); } return Polynomial(terms); } else if (factors.length == 2 && 2 in factors) { // n = 2^h * p^k auto p = 0; auto k = 0; foreach (prime, v; factors) { if (prime != 2 && prime > p) { p = prime; k = v; } } Term[] terms; auto coeff = -1; auto twoExp = 2 ^^ (factors[2] - 1); foreach (i; 0..p) { coeff *= -1; auto exponent = i * twoExp * p ^^ (k - 1); terms ~= Term(coeff, exponent); } return Polynomial(terms); } else if (2 in factors && n / 2 % 2 == 1 && n / 2 > 1) { // CP(2m)[x] = CP(-m)[x], n odd integer > 1 auto cycloDiv2 = memoize!cyclotomicPolynomialImpl(n / 2); Term[] terms; foreach (term; cycloDiv2) { if (term.exponent() % 2 == 0) { terms ~= term; } else { terms ~= -term; } } return Polynomial(terms); }   if (ALGORITHM == 0) { // Slow - uses basic definition. auto divisors = getDivisors(n); // Polynomial: ( x^n - 1 ) auto cyclo = Polynomial(Term(1, n), Term(-1, 0)); foreach (i; divisors) { auto p = memoize!cyclotomicPolynomialImpl(i); cyclo = cyclo / p; } return cyclo; } if (ALGORITHM == 1) { // Faster. Remove Max divisor (and all divisors of max divisor) - only one divide for all divisors of Max Divisor auto divisors = getDivisors(n); auto maxDivisor = int.min; foreach (div; divisors) { maxDivisor = max(maxDivisor, div); } int[] divisorsExceptMax; foreach (div; divisors) { if (maxDivisor % div != 0) { divisorsExceptMax ~= div; } }   // Polynomial: ( x^n - 1 ) / ( x^m - 1 ), where m is the max divisor auto cyclo = Polynomial(Term(1, n), Term(-1, 0)) / Polynomial(Term(1, maxDivisor), Term(-1, 0)); foreach (i; divisorsExceptMax) { auto p = memoize!cyclotomicPolynomialImpl(i); cyclo = cyclo / p; } return cyclo; } if (ALGORITHM == 2) { // Fastest // Let p ; q be primes such that p does not divide n, and q q divides n. // Then CP(np)[x] = CP(n)[x^p] / CP(n)[x] auto m = 1; auto cyclo = memoize!cyclotomicPolynomialImpl(m); auto primes = factors.keys; primes.sort; foreach (prime; primes) { // CP(m)[x] auto cycloM = cyclo; // Compute CP(m)[x^p]. Term[] terms; foreach (term; cycloM) { terms ~= Term(term.coefficient(), term.exponent() * prime); } cyclo = Polynomial(terms) / cycloM; m *= prime; } // Now, m is the largest square free divisor of n auto s = n / m; // Compute CP(n)[x] = CP(m)[x^s] Term[] terms; foreach (term; cyclo) { terms ~= Term(term.coefficient(), term.exponent() * s); } return Polynomial(terms); } assert(false, "Error 103: Invalid algorithm"); } alias cyclotomicPolynomial = memoize!cyclotomicPolynomialImpl;   void main() { writeln("Task 1: cyclotomic polynomials for n <= 30:"); foreach (i; 1 .. 31) { auto p = cyclotomicPolynomial(i); writefln("CP[%d] = %s", i, p); } writeln;   writeln("Task 2: Smallest cyclotomic polynomial with n or -n as a coefficient:"); auto n = 0; foreach (i; 1 .. 11) { while (true) { n++; auto cyclo = cyclotomicPolynomial(n); if (cyclo.hasCoefficientAbs(i)) { writefln("CP[%d] has coefficient with magnitude = %d", n, i); n--; break; } } } }
http://rosettacode.org/wiki/Cut_a_rectangle
Cut a rectangle
A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such paths for 2 × 2 and 4 × 3 rectangles are shown below. Write a program that calculates the number of different ways to cut an m × n rectangle. Optionally, show each of the cuts. Possibly related task: Maze generation for depth-first search.
#Groovy
Groovy
class CutRectangle { private static int[][] dirs = [[0, -1], [-1, 0], [0, 1], [1, 0]]   static void main(String[] args) { cutRectangle(2, 2) cutRectangle(4, 3) }   static void cutRectangle(int w, int h) { if (w % 2 == 1 && h % 2 == 1) { return }   int[][] grid = new int[h][w] Stack<Integer> stack = new Stack<>()   int half = (int) ((w * h) / 2) long bits = (long) Math.pow(2, half) - 1   for (; bits > 0; bits -= 2) { for (int i = 0; i < half; i++) { int r = (int) (i / w) int c = i % w grid[r][c] = (bits & (1 << i)) != 0 ? 1 : 0 grid[h - r - 1][w - c - 1] = 1 - grid[r][c] }   stack.push(0) grid[0][0] = 2 int count = 1 while (!stack.empty()) { int pos = stack.pop() int r = (int) (pos / w) int c = pos % w   for (int[] dir : dirs) { int nextR = r + dir[0] int nextC = c + dir[1]   if (nextR >= 0 && nextR < h && nextC >= 0 && nextC < w) { if (grid[nextR][nextC] == 1) { stack.push(nextR * w + nextC) grid[nextR][nextC] = 2 count++ } } } } if (count == half) { printResult(grid) } } }   static void printResult(int[][] arr) { for (int[] a : arr) { println(Arrays.toString(a)) } println() } }
http://rosettacode.org/wiki/Cyclops_numbers
Cyclops numbers
A cyclops number is a number with an odd number of digits that has a zero in the center, but nowhere else. They are named so in tribute to the one eyed giants Cyclops from Greek mythology. Cyclops numbers can be found in any base. This task strictly is looking for cyclops numbers in base 10. There are many different classifications of cyclops numbers with minor differences in characteristics. In an effort to head off a whole series of tasks with tiny variations, we will cover several variants here. Task Find and display here on this page the first 50 cyclops numbers in base 10 (all of the sub tasks are restricted to base 10). Find and display here on this page the first 50 prime cyclops numbers. (cyclops numbers that are prime.) Find and display here on this page the first 50 blind prime cyclops numbers. (prime cyclops numbers that remain prime when "blinded"; the zero is removed from the center.) Find and display here on this page the first 50 palindromic prime cyclops numbers. (prime cyclops numbers that are palindromes.) Stretch Find and display the first cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first blind prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first palindromic prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. (Note: there are no cyclops numbers between ten million and one hundred million, they need to have an odd number of digits) See also OEIS A134808 - Cyclops numbers OEIS A134809 - Cyclops primes OEIS A329737 - Cyclops primes that remain prime after being "blinded" OEIS A136098 - Prime palindromic cyclops numbers
#Ruby
Ruby
require 'prime'   NONZEROS = %w(1 2 3 4 5 6 7 8 9)   cyclopes = Enumerator.new do |y| (0..).each do |n| NONZEROS.repeated_permutation(n) do |lside| NONZEROS.repeated_permutation(n) do |rside| y << (lside.join + "0" + rside.join).to_i end end end end   prime_cyclopes = Enumerator.new {|y| cyclopes.each {|c| y << c if c.prime?} } blind_prime_cyclopes = Enumerator.new {|y| prime_cyclopes.each {|c| y << c if c.to_s.delete("0").to_i.prime?} } palindromic_prime_cyclopes = Enumerator.new {|y| prime_cyclopes.each {|c| y << c if c.to_s == c.to_s.reverse} }   n, m = 50, 10_000_000 ["cyclopes", "prime cyclopes", "blind prime cyclopes", "palindromic prime cyclopes"].zip( [cyclopes, prime_cyclopes, blind_prime_cyclopes, palindromic_prime_cyclopes]).each do |name, enum| cycl, idx = enum.each_with_index.detect{|n, i| n > m} puts "The first #{n} #{name} are: \n#{enum.take(n).to_a}\nFirst #{name} term > #{m}: #{cycl} at index: #{idx}.", "" end  
http://rosettacode.org/wiki/Date_manipulation
Date manipulation
Task Given the date string "March 7 2009 7:30pm EST", output the time 12 hours later in any human-readable format. As extra credit, display the resulting time in a time zone different from your own.
#Crystal
Crystal
time = Time.parse("March 7 2009 7:30pm EST", "%B %-d %Y %l:%M%p", Time::Location.load("EST"))   time += 12.hours puts time # 2009-03-08 07:30:00 -05:00 puts time.in(Time::Location.load("Europe/Berlin")) # 2009-03-08 13:30:00 +01:00  
http://rosettacode.org/wiki/Date_manipulation
Date manipulation
Task Given the date string "March 7 2009 7:30pm EST", output the time 12 hours later in any human-readable format. As extra credit, display the resulting time in a time zone different from your own.
#D
D
  import std.stdio; import std.format; import std.datetime; import std.algorithm;   enum months = ["January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"];   void main() { // input string date = "March 7 2009 7:30pm EST";   // parsing date string to integer values string month, md, tz; int day, year, hour, minute; date.formattedRead("%s %d %d %d:%d%s %s", &month, &day, &year, &hour, &minute, &md, &tz); int mon = cast (int) months.countUntil(month) + 1;   // convert to 24-hour if (md == "pm") hour += 12;   // create date from integer DateTime dt = DateTime(year, mon, day, hour, minute);   // output writeln(dt); writeln(dt + 12.hours);   }    
http://rosettacode.org/wiki/Deal_cards_for_FreeCell
Deal cards for FreeCell
Free Cell is the solitaire card game that Paul Alfille introduced to the PLATO system in 1978. Jim Horne, at Microsoft, changed the name to FreeCell and reimplemented the game for DOS, then Windows. This version introduced 32000 numbered deals. (The FreeCell FAQ tells this history.) As the game became popular, Jim Horne disclosed the algorithm, and other implementations of FreeCell began to reproduce the Microsoft deals. These deals are numbered from 1 to 32000. Newer versions from Microsoft have 1 million deals, numbered from 1 to 1000000; some implementations allow numbers outside that range. The algorithm uses this linear congruential generator from Microsoft C: s t a t e n + 1 ≡ 214013 × s t a t e n + 2531011 ( mod 2 31 ) {\displaystyle state_{n+1}\equiv 214013\times state_{n}+2531011{\pmod {2^{31}}}} r a n d n = s t a t e n ÷ 2 16 {\displaystyle rand_{n}=state_{n}\div 2^{16}} r a n d n {\displaystyle rand_{n}} is in range 0 to 32767. Rosetta Code has another task, linear congruential generator, with code for this RNG in several languages. The algorithm follows: Seed the RNG with the number of the deal. Create an array of 52 cards: Ace of Clubs, Ace of Diamonds, Ace of Hearts, Ace of Spades, 2 of Clubs, 2 of Diamonds, and so on through the ranks: Ace, 2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen, King. The array indexes are 0 to 51, with Ace of Clubs at 0, and King of Spades at 51. Until the array is empty: Choose a random card at index ≡ next random number (mod array length). Swap this random card with the last card of the array. Remove this random card from the array. (Array length goes down by 1.) Deal this random card. Deal all 52 cards, face up, across 8 columns. The first 8 cards go in 8 columns, the next 8 cards go on the first 8 cards, and so on. Order to deal cards Game #1 Game #617 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 JD 2D 9H JC 5D 7H 7C 5H KD KC 9S 5S AD QC KH 3H 2S KS 9D QD JS AS AH 3C 4C 5C TS QH 4H AC 4D 7S 3S TD 4S TH 8H 2C JH 7D 6D 8S 8D QS 6C 3D 8C TC 6S 9C 2H 6H 7D AD 5C 3S 5S 8C 2D AH TD 7S QD AC 6D 8H AS KH TH QC 3H 9D 6S 8D 3D TC KD 5H 9S 3C 8S 7H 4D JS 4C QS 9C 9H 7C 6H 2C 2S 4S TS 2H 5D JC 6C JH QH JD KS KC 4H Deals can also be checked against FreeCell solutions to 1000000 games. (Summon a video solution, and it displays the initial deal.) Write a program to take a deal number and deal cards in the same order as this algorithm. The program may display the cards with ASCII, with Unicode, by drawing graphics, or any other way. Related tasks: Playing cards Card shuffles War Card_Game Poker hand_analyser Go Fish
#Perl
Perl
#!/usr/bin/perl   use strict; use warnings;   use utf8;   sub deal { my $s = shift;   my $rnd = sub { return (($s = ($s * 214013 + 2531011) & 0x7fffffff) >> 16 ); };   my @d; for my $b (split "", "A23456789TJQK") { push @d, map("$_$b", qw/♣ ♦ ♥ ♠/); }   for my $idx (reverse 0 .. $#d) { my $r = $rnd->() % ($idx + 1); @d[$r, $idx] = @d[$idx, $r]; }   return [reverse @d]; }   my $hand_idx = shift(@ARGV) // 11_982;   my $cards = deal($hand_idx);   my $num_cards_in_height = 8; my $string = '';   while (@$cards) { $string .= join(' ', splice(@$cards, 0, 8)) . "\n"; }   binmode STDOUT, ':encoding(utf-8)'; print "Hand $hand_idx\n"; print $string;
http://rosettacode.org/wiki/Define_a_primitive_data_type
Define a primitive data type
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
#Toka
Toka
needs quotes { variable update [ update @ [ ! ] [ @ ] ifTrueFalse update off ] is action [ dup >r 0 11 r> within [ update on ] [ drop ." Out of bounds\n " ] ifTrueFalse ] [ ` [ invoke cell-size malloc # ` action compile ` ] invoke is ] } is value:1-10: is to   value:1-10: foo 1 to foo foo .
http://rosettacode.org/wiki/Define_a_primitive_data_type
Define a primitive data type
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
#UNIX_Shell
UNIX Shell
typeset -i boundedint function boundedint.set { nameref var=${.sh.name} if (( 1 <= .sh.value && .sh.value <= 10 )); then # stash the valid value as a backup, in case we need to restore it typeset -i var.previous_value=${.sh.value} else print -u2 "value out of bounds" # restore previous value .sh.value=${var.previous_value} fi }   boundedint=-5; echo $boundedint boundedint=5; echo $boundedint boundedint=15; echo $boundedint
http://rosettacode.org/wiki/Day_of_the_week
Day of the week
A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January). Task In what years between 2008 and 2121 will the 25th of December be a Sunday? Using any standard date handling libraries of your programming language; compare the dates calculated with the output of other languages to discover any anomalies in the handling of dates which may be due to, for example, overflow in types used to represent dates/times similar to   y2k   type problems.
#Clojure
Clojure
  (import '(java.util GregorianCalendar)) (defn yuletide [start end] (filter #(= (. (new GregorianCalendar % (. GregorianCalendar DECEMBER) 25) get (. GregorianCalendar DAY_OF_WEEK)) (. GregorianCalendar SUNDAY)) (range start (inc end))))   (yuletide 2008 2121)  
http://rosettacode.org/wiki/CUSIP
CUSIP
This page uses content from Wikipedia. The original article was at CUSIP. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) A   CUSIP   is a nine-character alphanumeric code that identifies a North American financial security for the purposes of facilitating clearing and settlement of trades. The CUSIP was adopted as an American National Standard under Accredited Standards X9.6. Task Ensure the last digit   (i.e., the   check digit)   of the CUSIP code (the 1st column) is correct, against the following:   037833100       Apple Incorporated   17275R102       Cisco Systems   38259P508       Google Incorporated   594918104       Microsoft Corporation   68389X106       Oracle Corporation   (incorrect)   68389X105       Oracle Corporation Example pseudo-code below. algorithm Cusip-Check-Digit(cusip) is Input: an 8-character CUSIP   sum := 0 for 1 ≤ i ≤ 8 do c := the ith character of cusip if c is a digit then v := numeric value of the digit c else if c is a letter then p := ordinal position of c in the alphabet (A=1, B=2...) v := p + 9 else if c = "*" then v := 36 else if c = "@" then v := 37 else if' c = "#" then v := 38 end if if i is even then v := v × 2 end if   sum := sum + int ( v div 10 ) + v mod 10 repeat   return (10 - (sum mod 10)) mod 10 end function See related tasks SEDOL ISIN
#AutoHotkey
AutoHotkey
Cusip_Check_Digit(cusip){ sum := 0, i := 1, x := StrSplit(cusip) while (i <= 8) { c := x[i] if c is digit v := c else if c is alpha v := Asc(c) - 64 + 9 else if (c = "*") v := 36 else if (c = "@") v := 37 else if (c = "#") v := 38 if (i/2 = Floor(i/2)) v *= 2 sum += Floor(v/10) + Mod(v, 10) i++ } return (Mod(10 - Mod(sum, 10), 10) = x[9]) }
http://rosettacode.org/wiki/Date_format
Date format
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the   current date   in the formats of:   2007-11-23     and   Friday, November 23, 2007
#ARM_Assembly
ARM Assembly
  /* ARM assembly Raspberry PI */ /* program dateFormat.s */   /* REMARK 1 : this program use routines in a include file see task Include a file language arm assembly for the routine affichageMess conversion10 see at end of this program the instruction include */   /*******************************************/ /* Constantes */ /*******************************************/ .equ STDOUT, 1 @ Linux output console .equ EXIT, 1 @ Linux syscall .equ WRITE, 4 @ Linux syscall .equ BRK, 0x2d @ Linux syscall .equ CHARPOS, '@'   .equ GETTIME, 0x4e @ call system linux gettimeofday   /*******************************************/ /* Structures */ /********************************************/ /* example structure time */ .struct 0 timeval_sec: @ .struct timeval_sec + 4 timeval_usec: @ .struct timeval_usec + 4 timeval_end: .struct 0 timezone_min: @ .struct timezone_min + 4 timezone_dsttime: @ .struct timezone_dsttime + 4 timezone_end:   /*********************************/ /* Initialized data */ /*********************************/ .data szMessError: .asciz "Error detected !!!!. \n" szMessResult: .asciz "Date : @/@/@ \n" @ message result szMessResult1: .asciz "Date day : @ @ @ @ \n" @ message result szJan: .asciz "Janvier" szFev: .asciz "Février" szMars: .asciz "Mars" szAvril: .asciz "Avril" szMai: .asciz "Mai" szJuin: .asciz "Juin" szJuil: .asciz "Juillet" szAout: .asciz "Aout" szSept: .asciz "Septembre" szOct: .asciz "Octobre" szNov: .asciz "Novembre" szDec: .asciz "Décembre" szLundi: .asciz "Lundi" szMardi: .asciz "Mardi" szMercredi: .asciz "Mercredi" szJeudi: .asciz "Jeudi" szVendredi: .asciz "Vendredi" szSamedi: .asciz "Samedi" szDimanche: .asciz "Dimanche" szCarriageReturn: .asciz "\n" .align 4 tbDayMonthYear: .int 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335 .int 366, 397, 425, 456, 486, 517, 547, 578, 609, 639, 670, 700 .int 731, 762, 790, 821, 851, 882, 912, 943, 974,1004,1035,1065 .int 1096,1127,1155,1186,1216,1247,1277,1308,1339,1369,1400,1430 tbMonthName: .int szJan .int szFev .int szMars .int szAvril .int szMai .int szJuin .int szJuil .int szAout .int szSept .int szOct .int szNov .int szDec tbDayName: .int szLundi .int szMardi .int szMercredi .int szJeudi .int szVendredi .int szSamedi .int szDimanche   /*********************************/ /* UnInitialized data */ /*********************************/ .bss .align 4 stTVal: .skip timeval_end stTZone: .skip timezone_end sZoneConv: .skip 100 /*********************************/ /* code section */ /*********************************/ .text .global main main: @ entry of program ldr r0,iAdrstTVal ldr r1,iAdrstTZone mov r7,#GETTIME svc 0 cmp r0,#-1 @ error ? beq 99f ldr r1,iAdrstTVal ldr r0,[r1,#timeval_sec] @ timestemp in second bl dateFormatNum ldr r0,[r1,#timeval_sec] @ timestemp in second bl dateFormatAlpha ldr r0,iTStest1 bl dateFormatNum ldr r0,iTStest1 bl dateFormatAlpha ldr r0,iTStest2 bl dateFormatNum ldr r0,iTStest2 bl dateFormatAlpha ldr r0,iTStest3 bl dateFormatNum ldr r0,iTStest3 bl dateFormatAlpha b 100f 99: ldr r0,iAdrszMessError bl affichageMess 100: @ standard end of the program mov r0,#0 @ return code mov r7,#EXIT @ request to exit program svc 0 @ perform the system call   iAdrszMessError: .int szMessError iAdrstTVal: .int stTVal iAdrstTZone: .int stTZone iAdrszCarriageReturn: .int szCarriageReturn iAdrsZoneConv: .int sZoneConv iTStest1: .int 1609508339 @ 01/01/2021 iTStest2: .int 1657805939 @ 14/07/2022 iTStest3: .int 1767221999 @ 31/12/2025 /******************************************************************/ /* date format numeric */ /******************************************************************/ /* r0 contains the timestamp in seconds */ dateFormatNum: push {r1-r11,lr} @ save registers ldr r2,iSecJan2020 sub r0,r0,r2 @ total secondes to 01/01/2020 mov r1,#60 bl division mov r0,r2 mov r6,r3 @ compute secondes mov r1,#60 bl division mov r7,r3 @ compute minutes mov r0,r2 mov r1,#24 bl division mov r8,r3 @ compute hours mov r0,r2 mov r11,r0 mov r1,#(365 * 4 + 1) bl division lsl r9,r2,#2 @ multiply by 4 = year1 mov r1,#(365 * 4 + 1) mov r0,r11 bl division mov r10,r3   ldr r1,iAdrtbDayMonthYear mov r2,#3 mov r3,#12 1: mul r11,r3,r2 ldr r4,[r1,r11,lsl #2] @ load days by year cmp r10,r4 bge 2f sub r2,r2,#1 cmp r2,#0 bne 1b 2: @ r2 = year2 mov r5,#11 mul r11,r3,r2 lsl r11,#2 add r11,r1 @ table address 3: ldr r4,[r11,r5,lsl #2] @ load days by month cmp r10,r4 bge 4f subs r5,r5,#1 bne 3b 4: @ r5 = month - 1 mul r11,r3,r2 add r11,r5 ldr r1,iAdrtbDayMonthYear ldr r3,[r1,r11,lsl #2] sub r0,r10,r3 add r0,r0,#1 @ final compute day ldr r1,iAdrsZoneConv bl conversion10 @ this function do not zero final mov r11,#0 @ store zero final strb r11,[r1,r0] ldr r0,iAdrszMessResult ldr r1,iAdrsZoneConv bl strInsertAtCharInc @ insert result at first @ character mov r3,r0 add r0,r5,#1 @ final compute month cmp r0,#12 subgt r0,#12 ldr r1,iAdrsZoneConv bl conversion10 mov r11,#0 @ store zero final strb r11,[r1,r0] mov r0,r3 ldr r1,iAdrsZoneConv bl strInsertAtCharInc @ insert result at next @ character mov r3,r0 ldr r11,iYearStart add r0,r9,r11 add r0,r0,r2 @ final compute year = 2020 + year1 + year2 ldr r1,iAdrsZoneConv bl conversion10 mov r11,#0 @ store zero final strb r11,[r1,r0] mov r0,r3 ldr r1,iAdrsZoneConv bl strInsertAtCharInc @ insert result at next @ character bl affichageMess 100: pop {r1-r11,lr} @ restaur registers bx lr @ return iAdrszMessResult: .int szMessResult /******************************************************************/ /* date format alphanumeric */ /******************************************************************/ /* r0 contains the timestamp in seconds */ dateFormatAlpha: push {r1-r10,lr} @ save registers ldr r2,iSecJan2020 sub r0,r0,r2 @ total secondes to 01/01/2020 mov r6,r0 mov r1,#60 bl division mov r0,r2 mov r1,#60 bl division mov r0,r2 mov r1,#24 bl division mov r0,r2 mov r8,r0 mov r1,#(365 * 4 + 1) bl division lsl r9,r2,#2 @ multiply by 4 = year1 mov r1,#(365 * 4 + 1) mov r0,r8 bl division mov r10,r3 @ reste   ldr r1,iAdrtbDayMonthYear mov r7,#3 mov r3,#12 1: mul r8,r3,r7 ldr r4,[r1,r8,lsl #2] @ load days by year cmp r10,r4 bge 2f sub r7,r7,#1 cmp r7,#0 bne 1b 2: @ r7 = year2 mov r5,#11 mul r8,r3,r7 lsl r8,#2 add r8,r1 3: ldr r4,[r8,r5,lsl #2] @ load days by month cmp r10,r4 bge 4f subs r5,r5,#1 bne 3b 4: @ r5 = month - 1   mov r0,r6 @ number secondes depuis 01/01/2020 ldr r1,iNbSecByDay bl division mov r0,r2 mov r1,#7 bl division add r2,r3,#2 cmp r2,#7 subge r2,#7 ldr r1,iAdrtbDayName ldr r1,[r1,r2,lsl #2] ldr r0,iAdrszMessResult1 bl strInsertAtCharInc @ insert result at next @ character mov r3,r0 mov r8,#12 mul r11,r8,r7 add r11,r5 ldr r1,iAdrtbDayMonthYear ldr r8,[r1,r11,lsl #2] sub r0,r10,r8 add r0,r0,#1 @ final compute day ldr r1,iAdrsZoneConv bl conversion10 @ this function do not zero final mov r8,#0 @ store zero final strb r8,[r1,r0] mov r0,r3 ldr r1,iAdrsZoneConv bl strInsertAtCharInc @ insert result at first @ character mov r3,r0 ldr r1,iAdrtbMonthName cmp r5,#12 subge r5,#12 ldr r1,[r1,r5,lsl #2] @ month name mov r0,r3 bl strInsertAtCharInc @ insert result at first @ character mov r3,r0 ldr r0,iYearStart add r0,r7 add r0,r9 @ final compute year = 2020 + year1 + year2   ldr r1,iAdrsZoneConv bl conversion10 @ this function do not zero final mov r8,#0 @ store zero final strb r8,[r1,r0] mov r0,r3 ldr r1,iAdrsZoneConv bl strInsertAtCharInc @ insert result at first @ character bl affichageMess 100: pop {r1-r10,lr} @ restaur registers bx lr @ return iAdrszMessResult1: .int szMessResult1 iSecJan2020: .int 1577836800 iAdrtbDayMonthYear: .int tbDayMonthYear iYearStart: .int 2020 iAdrtbMonthName: .int tbMonthName iAdrtbDayName: .int tbDayName iNbSecByDay: .int 3600 * 24 /***************************************************/ /* ROUTINES INCLUDE */ /***************************************************/ .include "../affichage.inc"  
http://rosettacode.org/wiki/Damm_algorithm
Damm algorithm
The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors. The algorithm is named after H. Michael Damm. Task Verify the checksum, stored as last digit of an input.
#BASIC
BASIC
10 DEFINT D,I,X,Y: DIM DT(9,9) 20 FOR Y=0 TO 9: FOR X=0 TO 9: READ DT(X,Y): NEXT X,Y 30 INPUT N$: IF N$="" THEN END 40 D=0 50 FOR I=1 TO LEN(N$): D=DT(VAL(MID$(N$,I,1)),D): NEXT I 60 IF D THEN PRINT "FAIL" ELSE PRINT "PASS" 70 GOTO 30 100 DATA 0,3,1,7,5,9,8,6,4,2 110 DATA 7,0,9,2,1,5,4,8,6,3 120 DATA 4,2,0,6,8,7,1,3,5,9 130 DATA 1,7,5,0,9,8,3,4,2,6 140 DATA 6,1,2,3,0,4,5,9,7,8 150 DATA 3,6,7,4,2,0,9,5,8,1 160 DATA 5,8,6,9,7,2,0,1,3,4 170 DATA 8,9,4,5,3,6,2,0,1,7 180 DATA 9,4,3,8,6,1,7,2,0,5 190 DATA 2,5,8,1,4,3,6,7,9,0
http://rosettacode.org/wiki/Currying
Currying
This page uses content from Wikipedia. The original article was at Currying. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Create a simple demonstrative example of Currying in a specific language. Add any historic details as to how the feature made its way into the language.
#11l
11l
F addN(n) F adder(x) R x + @=n R adder   V add2 = addN(2) V add3 = addN(3) print(add2(7)) print(add3(7))
http://rosettacode.org/wiki/Cyclotomic_polynomial
Cyclotomic polynomial
The nth Cyclotomic polynomial, for any positive integer n, is the unique irreducible polynomial of largest degree with integer coefficients that is a divisor of x^n − 1, and is not a divisor of x^k − 1 for any k < n. Task Find and print the first 30 cyclotomic polynomials. Find and print the order of the first 10 cyclotomic polynomials that have n or -n as a coefficient. See also Wikipedia article, Cyclotomic polynomial, showing ways to calculate them. The sequence A013594 with the smallest order of cyclotomic polynomial containing n or -n as a coefficient.
#Fermat
Fermat
  &(J=x); {adjoin x as the variable in the polynomials}   Func Cyclotomic(n) = if n=1 then x-1 fi; {first cyclotomic polynomial is x^n-1} r:=x^n-1; {caclulate cyclotomic by division} for d = 1 to n-1 do if Divides(d,n) then r:=r\Cyclotomic(d) fi; od; r.; {return the polynomial}   Func Hascoef(n, k) = p:=Cyclotomic(n); for d = 0 to Deg(p) do if |(Coef(p,d))|=k then Return(1) fi od; 0.;   for d = 1 to 30 do  !!(d,' : ',Cyclotomic(d)) od;   for m = 1 to 10 do i:=1; while not Hascoef(i, m) do i:+ od;  !!(m,'  : ',i); od;
http://rosettacode.org/wiki/Cut_a_rectangle
Cut a rectangle
A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such paths for 2 × 2 and 4 × 3 rectangles are shown below. Write a program that calculates the number of different ways to cut an m × n rectangle. Optionally, show each of the cuts. Possibly related task: Maze generation for depth-first search.
#Haskell
Haskell
import qualified Data.Vector.Unboxed.Mutable as V import Data.STRef import Control.Monad (forM_, when) import Control.Monad.ST   dir :: [(Int, Int)] dir = [(1, 0), (-1, 0), (0, -1), (0, 1)]   data Env = Env { w, h, len, count, ret :: !Int, next :: ![Int] }   cutIt :: STRef s Env -> ST s () cutIt env = do e <- readSTRef env when (odd $ h e) $ modifySTRef env $ \en -> en { h = w e, w = h e } e <- readSTRef env if odd (h e) then modifySTRef env $ \en -> en { ret = 0 } else if w e == 1 then modifySTRef env $ \en -> en { ret = 1 } else do let blen = (h e + 1) * (w e + 1) - 1 t = (h e `div` 2) * (w e + 1) + (w e `div` 2) modifySTRef env $ \en -> en { len = blen, count = 0, next = [ w e + 1, (negate $ w e) - 1, -1, 1] } grid <- V.replicate (blen + 1) False case odd (w e) of True -> do V.write grid t True V.write grid (t + 1) True walk grid (h e `div` 2) (w e `div` 2 - 1) e1 <- readSTRef env let res1 = count e1 modifySTRef env $ \en -> en { count = 0 } walk grid (h e `div` 2 - 1) (w e `div` 2) modifySTRef env $ \en -> en { ret = res1 + (count en * 2) } False -> do V.write grid t True walk grid (h e `div` 2) (w e `div` 2 - 1) e2 <- readSTRef env let count2 = count e2 if h e == w e then modifySTRef env $ \en -> en { ret = count2 * 2 } else do walk grid (h e `div` 2 - 1) (w e `div` 2) modifySTRef env $ \en -> en { ret = count en } where walk grid y x = do e <- readSTRef env if y <= 0 || y >= h e || x <= 0 || x >= w e then modifySTRef env $ \en -> en { count = count en + 1 } else do let t = y * (w e + 1) + x V.write grid t True V.write grid (len e - t) True forM_ (zip (next e) [0..3]) $ \(n, d) -> do g <- V.read grid (t + n) when (not g) $ walk grid (y + fst (dir !! d)) (x + snd (dir !! d)) V.write grid t False V.write grid (len e - t) False   cut :: (Int, Int) -> Int cut (x, y) = runST $ do env <- newSTRef $ Env { w = y, h = x, len = 0, count = 0, ret = 0, next = [] } cutIt env result <- readSTRef env return $ ret result   main :: IO () main = do mapM_ (\(x, y) -> when (even (x * y)) (putStrLn $ show x ++ " x " ++ show y ++ ": " ++ show (cut (x, y)))) [ (x, y) | x <- [1..10], y <- [1..x] ]  
http://rosettacode.org/wiki/Cyclops_numbers
Cyclops numbers
A cyclops number is a number with an odd number of digits that has a zero in the center, but nowhere else. They are named so in tribute to the one eyed giants Cyclops from Greek mythology. Cyclops numbers can be found in any base. This task strictly is looking for cyclops numbers in base 10. There are many different classifications of cyclops numbers with minor differences in characteristics. In an effort to head off a whole series of tasks with tiny variations, we will cover several variants here. Task Find and display here on this page the first 50 cyclops numbers in base 10 (all of the sub tasks are restricted to base 10). Find and display here on this page the first 50 prime cyclops numbers. (cyclops numbers that are prime.) Find and display here on this page the first 50 blind prime cyclops numbers. (prime cyclops numbers that remain prime when "blinded"; the zero is removed from the center.) Find and display here on this page the first 50 palindromic prime cyclops numbers. (prime cyclops numbers that are palindromes.) Stretch Find and display the first cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first blind prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. Find and display the first palindromic prime cyclops number greater than ten million (10,000,000) and the index (place) in the series where it is found. (Note: there are no cyclops numbers between ten million and one hundred million, they need to have an odd number of digits) See also OEIS A134808 - Cyclops numbers OEIS A134809 - Cyclops primes OEIS A329737 - Cyclops primes that remain prime after being "blinded" OEIS A136098 - Prime palindromic cyclops numbers
#Sidef
Sidef
func cyclops_numbers(base = 10) { Enumerator({|callback|   var digits = @(1 .. base-1)   for k in (0 .. Inf `by` 2) { digits.variations_with_repetition(k, {|*a| a = (a.first(a.len>>1) + [0] + a.last(a.len>>1)) callback(a.flip.digits2num(base)) }) } }) }   func palindromic_cyclops_numbers(base = 10) { Enumerator({|callback|   var digits = @(1 .. base-1)   for k in (0..Inf) { digits.variations_with_repetition(k, {|*a| a = (a + [0] + a.flip) callback(a.flip.digits2num(base)) }) } }) }   func prime_cyclops(base = 10) { var iter = cyclops_numbers(base) Enumerator({|callback| iter.each {|n| callback(n) if n.is_prime } }) }   func blind_prime_cyclops(base = 10) { var iter = prime_cyclops(base) Enumerator({|callback| iter.each {|n| var k = (n.len(base)-1)>>1 var r = ipow(base, k) if (r*idiv(n, r*base) + n%r -> is_prime) { callback(n) } } }) }   func palindromic_prime_cyclops(base = 10) { var iter = palindromic_cyclops_numbers(base) Enumerator({|callback| iter.each {|n| callback(n) if n.is_prime } }) }   for text,f in ([ ['', cyclops_numbers], ['prime', prime_cyclops], ['blind prime', blind_prime_cyclops], ['palindromic prime', palindromic_prime_cyclops], ]) {   with (50) {|k| say "First #{k} #{text} cyclops numbers:" f().first(k).each_slice(10, {|*a| a.map { '%7s' % _ }.join(' ').say }) }   var min = 10_000_000 var iter = f() var index = 0 var arr = Enumerator({|callback| iter.each {|n| callback([index, n]) if (n > min) ++index } }).first(1)[0] say "\nFirst #{text} term > #{min.commify}: #{arr[1].commify} at (zero based) index: #{arr[0].commify}\n" }
http://rosettacode.org/wiki/Date_manipulation
Date manipulation
Task Given the date string "March 7 2009 7:30pm EST", output the time 12 hours later in any human-readable format. As extra credit, display the resulting time in a time zone different from your own.
#Delphi
Delphi
  program DateManipulation;   {$APPTYPE CONSOLE}   uses SysUtils, DateUtils;   function MonthNumber(aMonth: string): Word; begin //Convert a string value representing the month //to its corresponding numerical value if aMonth = 'January' then Result:= 1 else if aMonth = 'February' then Result:= 2 else if aMonth = 'March' then Result:= 3 else if aMonth = 'April' then Result:= 4 else if aMonth = 'May' then Result:= 5 else if aMonth = 'June' then Result:= 6 else if aMonth = 'July' then Result:= 7 else if aMonth = 'August' then Result:= 8 else if aMonth = 'September' then Result:= 9 else if aMonth = 'October' then Result:= 10 else if aMonth = 'November' then Result:= 11 else if aMonth = 'December' then Result:= 12 else Result:= 12; end;   function ParseString(aDateTime: string): TDateTime; var strDay, strMonth, strYear, strTime: string; iDay, iMonth, iYear: Word; TimePortion: TDateTime; begin //Decode the month from the given string strMonth:= Copy(aDateTime, 1, Pos(' ', aDateTime) - 1); Delete(aDateTime, 1, Pos(' ', aDateTime)); iMonth:= MonthNumber(strMonth);   //Decode the day from the given string strDay:= Copy(aDateTime, 1, Pos(' ', aDateTime) - 1); Delete(aDateTime, 1, Pos(' ', aDateTime)); iDay:= StrToIntDef(strDay, 30);   //Decode the year from the given string strYear:= Copy(aDateTime, 1, Pos(' ', aDateTime) -1); Delete(aDateTime, 1, Pos(' ', aDateTime)); iYear:= StrToIntDef(strYear, 1899);   //Decode the time value from the given string strTime:= Copy(aDateTime, 1, Pos(' ', aDateTime) -1);   //Encode the date value and assign it to result Result:= EncodeDate(iYear, iMonth, iDay);   //Encode the time value and add it to result if TryStrToTime(strTime, TimePortion) then Result:= Result + TimePortion; end;   function Add12Hours(aDateTime: string): string; var tmpDateTime: TDateTime; begin //Adding 12 hours to the given //date time string value tmpDateTime:= ParseString(aDateTime); tmpDateTime:= IncHour(tmpDateTime, 12);   //Formatting the output Result:= FormatDateTime('mm/dd/yyyy hh:mm AM/PM', tmpDateTime); end;   begin Writeln(Add12Hours('March 7 2009 7:30pm EST')); Readln; end.  
http://rosettacode.org/wiki/Deal_cards_for_FreeCell
Deal cards for FreeCell
Free Cell is the solitaire card game that Paul Alfille introduced to the PLATO system in 1978. Jim Horne, at Microsoft, changed the name to FreeCell and reimplemented the game for DOS, then Windows. This version introduced 32000 numbered deals. (The FreeCell FAQ tells this history.) As the game became popular, Jim Horne disclosed the algorithm, and other implementations of FreeCell began to reproduce the Microsoft deals. These deals are numbered from 1 to 32000. Newer versions from Microsoft have 1 million deals, numbered from 1 to 1000000; some implementations allow numbers outside that range. The algorithm uses this linear congruential generator from Microsoft C: s t a t e n + 1 ≡ 214013 × s t a t e n + 2531011 ( mod 2 31 ) {\displaystyle state_{n+1}\equiv 214013\times state_{n}+2531011{\pmod {2^{31}}}} r a n d n = s t a t e n ÷ 2 16 {\displaystyle rand_{n}=state_{n}\div 2^{16}} r a n d n {\displaystyle rand_{n}} is in range 0 to 32767. Rosetta Code has another task, linear congruential generator, with code for this RNG in several languages. The algorithm follows: Seed the RNG with the number of the deal. Create an array of 52 cards: Ace of Clubs, Ace of Diamonds, Ace of Hearts, Ace of Spades, 2 of Clubs, 2 of Diamonds, and so on through the ranks: Ace, 2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen, King. The array indexes are 0 to 51, with Ace of Clubs at 0, and King of Spades at 51. Until the array is empty: Choose a random card at index ≡ next random number (mod array length). Swap this random card with the last card of the array. Remove this random card from the array. (Array length goes down by 1.) Deal this random card. Deal all 52 cards, face up, across 8 columns. The first 8 cards go in 8 columns, the next 8 cards go on the first 8 cards, and so on. Order to deal cards Game #1 Game #617 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 JD 2D 9H JC 5D 7H 7C 5H KD KC 9S 5S AD QC KH 3H 2S KS 9D QD JS AS AH 3C 4C 5C TS QH 4H AC 4D 7S 3S TD 4S TH 8H 2C JH 7D 6D 8S 8D QS 6C 3D 8C TC 6S 9C 2H 6H 7D AD 5C 3S 5S 8C 2D AH TD 7S QD AC 6D 8H AS KH TH QC 3H 9D 6S 8D 3D TC KD 5H 9S 3C 8S 7H 4D JS 4C QS 9C 9H 7C 6H 2C 2S 4S TS 2H 5D JC 6C JH QH JD KS KC 4H Deals can also be checked against FreeCell solutions to 1000000 games. (Summon a video solution, and it displays the initial deal.) Write a program to take a deal number and deal cards in the same order as this algorithm. The program may display the cards with ASCII, with Unicode, by drawing graphics, or any other way. Related tasks: Playing cards Card shuffles War Card_Game Poker hand_analyser Go Fish
#Phix
Phix
with javascript_semantics atom seed function xrnd() seed = and_bits(seed*214013+2531011,#7FFFFFFF) return floor(seed/power(2,16)) end function sequence cards = repeat(0,52) procedure deal(integer game_num) seed = game_num for i=1 to 52 do cards[i] = 52-i end for for i=1 to 51 do integer j = 52-mod(xrnd(),53-i) integer s = cards[i] cards[i] = cards[j] cards[j] = s end for end procedure constant suits = "CDHS", ranks = "A23456789TJQK" procedure show() for idx=1 to 52 do integer rank = floor(cards[idx]/4)+1 integer suit = mod(cards[idx],4)+1 integer eol = remainder(idx-1,13)=12 printf(1,"%c%c%s",{ranks[rank],suits[suit],iff(eol?"\n":" ")}) end for end procedure integer game_num = 1 --integer game_num=617 deal(game_num) printf(1,"hand %d\n",{game_num}) show()
http://rosettacode.org/wiki/Define_a_primitive_data_type
Define a primitive data type
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
#Ursala
Ursala
#import nat   my_number ::   the_number %n -|~bounds.&BZ,~&B+ nleq~~lrlXPrX@G+ ~/the_number bounds|-?(~the_number,<'out of bounds'>!%) bounds  %nW ~bounds.&B?(~bounds,(1,10)!)   add = my_number$[the_number: sum+ ~the_number~~] mul = my_number$[the_number: product+ ~the_number~~]
http://rosettacode.org/wiki/Define_a_primitive_data_type
Define a primitive data type
Demonstrate how to define a type that behaves like an integer but has a lowest valid value of 1 and a highest valid value of 10. Include all bounds checking you need to write, or explain how the compiler or interpreter creates those bounds checks for you.
#Visual_Basic
Visual Basic
Private mvarValue As Integer   Public Property Let Value(ByVal vData As Integer) If (vData > 10) Or (vData < 1) Then Error 380 'Invalid property value; could also use 6, Overflow Else mvarValue = vData End If End Property   Public Property Get Value() As Integer Value = mvarValue End Property   Private Sub Class_Initialize() 'vb defaults to 0 for numbers; let's change that... mvarValue = 1 End Sub
http://rosettacode.org/wiki/Day_of_the_week
Day of the week
A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January). Task In what years between 2008 and 2121 will the 25th of December be a Sunday? Using any standard date handling libraries of your programming language; compare the dates calculated with the output of other languages to discover any anomalies in the handling of dates which may be due to, for example, overflow in types used to represent dates/times similar to   y2k   type problems.
#CLU
CLU
weekday = proc (d: date) returns (int) y: int := d.year m: int := d.month if m<3 then y, m := y-1, m+10 else m := m-2 end c: int := y/100 y := y//100 z: int := (26*m-2)/10 + d.day + y + y/4 + c/4 - 2*c + 777 return(z//7) end weekday   start_up = proc () po: stream := stream$primary_output() for year: int in int$from_to(2008, 2121) do if weekday(date$create(25, 12, year, 0, 0, 0))=0 then stream$putl(po, int$unparse(year)) end end end start_up
http://rosettacode.org/wiki/CUSIP
CUSIP
This page uses content from Wikipedia. The original article was at CUSIP. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) A   CUSIP   is a nine-character alphanumeric code that identifies a North American financial security for the purposes of facilitating clearing and settlement of trades. The CUSIP was adopted as an American National Standard under Accredited Standards X9.6. Task Ensure the last digit   (i.e., the   check digit)   of the CUSIP code (the 1st column) is correct, against the following:   037833100       Apple Incorporated   17275R102       Cisco Systems   38259P508       Google Incorporated   594918104       Microsoft Corporation   68389X106       Oracle Corporation   (incorrect)   68389X105       Oracle Corporation Example pseudo-code below. algorithm Cusip-Check-Digit(cusip) is Input: an 8-character CUSIP   sum := 0 for 1 ≤ i ≤ 8 do c := the ith character of cusip if c is a digit then v := numeric value of the digit c else if c is a letter then p := ordinal position of c in the alphabet (A=1, B=2...) v := p + 9 else if c = "*" then v := 36 else if c = "@" then v := 37 else if' c = "#" then v := 38 end if if i is even then v := v × 2 end if   sum := sum + int ( v div 10 ) + v mod 10 repeat   return (10 - (sum mod 10)) mod 10 end function See related tasks SEDOL ISIN
#AWK
AWK
  # syntax: GAWK -f CUSIP.AWK BEGIN { n = split("037833100,17275R102,38259P508,594918104,68389X106,68389X105",arr,",") for (i=1; i<=n; i++) { printf("%9s %s\n",arr[i],cusip(arr[i])) } exit(0) } function cusip(n, c,i,sum,v,x) { # returns: 1=OK, 0=NG, -1=bad data if (length(n) != 9) { return(-1) } for (i=1; i<=8; i++) { c = substr(n,i,1) if (c ~ /[0-9]/) { v = c } else if (c ~ /[A-Z]/) { v = index("ABCDEFGHIJKLMNOPQRSTUVWXYZ",c) + 9 } else if (c == "*") { v = 36 } else if (c == "@") { v = 37 } else if (c == "#") { v = 38 } else { return(-1) } if (i ~ /[02468]/) { v *= 2 } sum += int(v / 10) + (v % 10) } x = (10 - (sum % 10)) % 10 return(substr(n,9,1) == x ? 1 : 0) }  
http://rosettacode.org/wiki/Date_format
Date format
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the   current date   in the formats of:   2007-11-23     and   Friday, November 23, 2007
#Arturo
Arturo
currentTime: now   print to :string.format: "YYYY-MM-dd" currentTime print to :string.format: "dddd, MMMM dd, YYYY" currentTime
http://rosettacode.org/wiki/Date_format
Date format
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the   current date   in the formats of:   2007-11-23     and   Friday, November 23, 2007
#AutoHotkey
AutoHotkey
FormatTime, Date1, , yyyy-MM-dd ; "2007-11-10" FormatTime, Date2, , LongDate ; "Sunday, November 10, 2007" MsgBox %Date1% `n %Date2%
http://rosettacode.org/wiki/Damm_algorithm
Damm algorithm
The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors. The algorithm is named after H. Michael Damm. Task Verify the checksum, stored as last digit of an input.
#BCPL
BCPL
get "libhdr"   let damm(ns) = valof $( let dt = table 0,3,1,7,5,9,8,6,4,2, 7,0,9,2,1,5,4,8,6,3, 4,2,0,6,8,7,1,3,5,9, 1,7,5,0,9,8,3,4,2,6, 6,1,2,3,0,4,5,9,7,8, 3,6,7,4,2,0,9,5,8,1, 5,8,6,9,7,2,0,1,3,4, 8,9,4,5,3,6,2,0,1,7, 9,4,3,8,6,1,7,2,0,5, 2,5,8,1,4,3,6,7,9,0 let idgt = 0 for i=1 to ns%0 test '0' <= ns%i <= '9' do idgt := dt!(ns%i-'0' + 10*idgt) or resultis false resultis idgt = 0 $)   let check(ns) be writef("%S: %S*N", ns, damm(ns) -> "pass", "fail")   let start() be $( check("5724") check("5727") check("112946") check("112949") $)
http://rosettacode.org/wiki/Damm_algorithm
Damm algorithm
The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors. The algorithm is named after H. Michael Damm. Task Verify the checksum, stored as last digit of an input.
#BQN
BQN
table ← >⟨ 0‿3‿1‿7‿5‿9‿8‿6‿4‿2 7‿0‿9‿2‿1‿5‿4‿8‿6‿3 4‿2‿0‿6‿8‿7‿1‿3‿5‿9 1‿7‿5‿0‿9‿8‿3‿4‿2‿6 6‿1‿2‿3‿0‿4‿5‿9‿7‿8 3‿6‿7‿4‿2‿0‿9‿5‿8‿1 5‿8‿6‿9‿7‿2‿0‿1‿3‿4 8‿9‿4‿5‿3‿6‿2‿0‿1‿7 9‿4‿3‿8‿6‿1‿7‿2‿0‿5 2‿5‿8‿1‿4‿3‿6‿7‿9‿0 ⟩     Digits ← 10{⌽𝕗|⌊∘÷⟜𝕗⍟(↕1+·⌊𝕗⋆⁼1⌈⊢)}   Damm ← {0=0(table⊑˜⋈)˜´⌽Digits 𝕩}   Damm¨5724‿5727‿112946
http://rosettacode.org/wiki/Currying
Currying
This page uses content from Wikipedia. The original article was at Currying. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Create a simple demonstrative example of Currying in a specific language. Add any historic details as to how the feature made its way into the language.
#Ada
Ada
generic type Argument_1 (<>) is limited private; type Argument_2 (<>) is limited private; type Argument_3 (<>) is limited private; type Return_Value (<>) is limited private;   with function Func (A : in Argument_1; B : in Argument_2; C : in Argument_3) return Return_Value; package Curry_3 is   generic First : in Argument_1; package Apply_1 is   generic Second : in Argument_2; package Apply_2 is   function Apply_3 (Third : in Argument_3) return Return_Value;   end Apply_2;   end Apply_1;   end Curry_3;
http://rosettacode.org/wiki/Currying
Currying
This page uses content from Wikipedia. The original article was at Currying. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) Task Create a simple demonstrative example of Currying in a specific language. Add any historic details as to how the feature made its way into the language.
#Aime
Aime
ri(list l) { l[0] = apply.apply(l[0]); } curry(object o) { (o.__count - 1).times(ri, list(o)); } main(void) { o_wbfxinteger.curry()(16)(3)(12)(16)(1 << 30); 0; }  
http://rosettacode.org/wiki/Cyclotomic_polynomial
Cyclotomic polynomial
The nth Cyclotomic polynomial, for any positive integer n, is the unique irreducible polynomial of largest degree with integer coefficients that is a divisor of x^n − 1, and is not a divisor of x^k − 1 for any k < n. Task Find and print the first 30 cyclotomic polynomials. Find and print the order of the first 10 cyclotomic polynomials that have n or -n as a coefficient. See also Wikipedia article, Cyclotomic polynomial, showing ways to calculate them. The sequence A013594 with the smallest order of cyclotomic polynomial containing n or -n as a coefficient.
#Go
Go
package main   import ( "fmt" "log" "math" "sort" "strings" )   const ( algo = 2 maxAllFactors = 100000 )   func iabs(i int) int { if i < 0 { return -i } return i }   type term struct{ coef, exp int }   func (t term) mul(t2 term) term { return term{t.coef * t2.coef, t.exp + t2.exp} }   func (t term) add(t2 term) term { if t.exp != t2.exp { log.Fatal("exponents unequal in term.add method") } return term{t.coef + t2.coef, t.exp} }   func (t term) negate() term { return term{-t.coef, t.exp} }   func (t term) String() string { switch { case t.coef == 0: return "0" case t.exp == 0: return fmt.Sprintf("%d", t.coef) case t.coef == 1: if t.exp == 1 { return "x" } else { return fmt.Sprintf("x^%d", t.exp) } case t.exp == 1: return fmt.Sprintf("%dx", t.coef) } return fmt.Sprintf("%dx^%d", t.coef, t.exp) }   type poly struct{ terms []term }   // pass coef, exp in pairs as parameters func newPoly(values ...int) poly { le := len(values) if le == 0 { return poly{[]term{term{0, 0}}} } if le%2 != 0 { log.Fatalf("odd number of parameters (%d) passed to newPoly function", le) } var terms []term for i := 0; i < le; i += 2 { terms = append(terms, term{values[i], values[i+1]}) } p := poly{terms}.tidy() return p }   func (p poly) hasCoefAbs(coef int) bool { for _, t := range p.terms { if iabs(t.coef) == coef { return true } } return false }   func (p poly) add(p2 poly) poly { p3 := newPoly() le, le2 := len(p.terms), len(p2.terms) for le > 0 || le2 > 0 { if le == 0 { p3.terms = append(p3.terms, p2.terms[le2-1]) le2-- } else if le2 == 0 { p3.terms = append(p3.terms, p.terms[le-1]) le-- } else { t := p.terms[le-1] t2 := p2.terms[le2-1] if t.exp == t2.exp { t3 := t.add(t2) if t3.coef != 0 { p3.terms = append(p3.terms, t3) } le-- le2-- } else if t.exp < t2.exp { p3.terms = append(p3.terms, t) le-- } else { p3.terms = append(p3.terms, t2) le2-- } } } return p3.tidy() }   func (p poly) addTerm(t term) poly { q := newPoly() added := false for i := 0; i < len(p.terms); i++ { ct := p.terms[i] if ct.exp == t.exp { added = true if ct.coef+t.coef != 0 { q.terms = append(q.terms, ct.add(t)) } } else { q.terms = append(q.terms, ct) } } if !added { q.terms = append(q.terms, t) } return q.tidy() }   func (p poly) mulTerm(t term) poly { q := newPoly() for i := 0; i < len(p.terms); i++ { ct := p.terms[i] q.terms = append(q.terms, ct.mul(t)) } return q.tidy() }   func (p poly) div(v poly) poly { q := newPoly() lcv := v.leadingCoef() dv := v.degree() for p.degree() >= v.degree() { lcp := p.leadingCoef() s := lcp / lcv t := term{s, p.degree() - dv} q = q.addTerm(t) p = p.add(v.mulTerm(t.negate())) } return q.tidy() }   func (p poly) leadingCoef() int { return p.terms[0].coef }   func (p poly) degree() int { return p.terms[0].exp }   func (p poly) String() string { var sb strings.Builder first := true for _, t := range p.terms { if first { sb.WriteString(t.String()) first = false } else { sb.WriteString(" ") if t.coef > 0 { sb.WriteString("+ ") sb.WriteString(t.String()) } else { sb.WriteString("- ") sb.WriteString(t.negate().String()) } } } return sb.String() }   // in place descending sort by term.exp func (p poly) sortTerms() { sort.Slice(p.terms, func(i, j int) bool { return p.terms[i].exp > p.terms[j].exp }) }   // sort terms and remove any unnecesary zero terms func (p poly) tidy() poly { p.sortTerms() if p.degree() == 0 { return p } for i := len(p.terms) - 1; i >= 0; i-- { if p.terms[i].coef == 0 { copy(p.terms[i:], p.terms[i+1:]) p.terms[len(p.terms)-1] = term{0, 0} p.terms = p.terms[:len(p.terms)-1] } } if len(p.terms) == 0 { p.terms = append(p.terms, term{0, 0}) } return p }   func getDivisors(n int) []int { var divs []int sqrt := int(math.Sqrt(float64(n))) for i := 1; i <= sqrt; i++ { if n%i == 0 { divs = append(divs, i) d := n / i if d != i && d != n { divs = append(divs, d) } } } return divs }   var ( computed = make(map[int]poly) allFactors = make(map[int]map[int]int) )   func init() { f := map[int]int{2: 1} allFactors[2] = f }   func getFactors(n int) map[int]int { if f, ok := allFactors[n]; ok { return f } factors := make(map[int]int) if n%2 == 0 { factorsDivTwo := getFactors(n / 2) for k, v := range factorsDivTwo { factors[k] = v } factors[2]++ if n < maxAllFactors { allFactors[n] = factors } return factors } prime := true sqrt := int(math.Sqrt(float64(n))) for i := 3; i <= sqrt; i += 2 { if n%i == 0 { prime = false for k, v := range getFactors(n / i) { factors[k] = v } factors[i]++ if n < maxAllFactors { allFactors[n] = factors } return factors } } if prime { factors[n] = 1 if n < maxAllFactors { allFactors[n] = factors } } return factors }   func cycloPoly(n int) poly { if p, ok := computed[n]; ok { return p } if n == 1 { // polynomial: x - 1 p := newPoly(1, 1, -1, 0) computed[1] = p return p } factors := getFactors(n) cyclo := newPoly() if _, ok := factors[n]; ok { // n is prime for i := 0; i < n; i++ { cyclo.terms = append(cyclo.terms, term{1, i}) } } else if len(factors) == 2 && factors[2] == 1 && factors[n/2] == 1 { // n == 2p prime := n / 2 coef := -1 for i := 0; i < prime; i++ { coef *= -1 cyclo.terms = append(cyclo.terms, term{coef, i}) } } else if len(factors) == 1 { if h, ok := factors[2]; ok { // n == 2^h cyclo.terms = append(cyclo.terms, term{1, 1 << (h - 1)}, term{1, 0}) } else if _, ok := factors[n]; !ok { // n == p ^ k p := 0 for prime := range factors { p = prime } k := factors[p] for i := 0; i < p; i++ { pk := int(math.Pow(float64(p), float64(k-1))) cyclo.terms = append(cyclo.terms, term{1, i * pk}) } } } else if len(factors) == 2 && factors[2] != 0 { // n = 2^h * p^k p := 0 for prime := range factors { if prime != 2 { p = prime } } coef := -1 twoExp := 1 << (factors[2] - 1) k := factors[p] for i := 0; i < p; i++ { coef *= -1 pk := int(math.Pow(float64(p), float64(k-1))) cyclo.terms = append(cyclo.terms, term{coef, i * twoExp * pk}) } } else if factors[2] != 0 && ((n/2)%2 == 1) && (n/2) > 1 { // CP(2m)[x] == CP(-m)[x], n odd integer > 1 cycloDiv2 := cycloPoly(n / 2) for _, t := range cycloDiv2.terms { t2 := t if t.exp%2 != 0 { t2 = t.negate() } cyclo.terms = append(cyclo.terms, t2) } } else if algo == 0 { // slow - uses basic definition divs := getDivisors(n) // polynomial: x^n - 1 cyclo = newPoly(1, n, -1, 0) for _, i := range divs { p := cycloPoly(i) cyclo = cyclo.div(p) } } else if algo == 1 { // faster - remove max divisor (and all divisors of max divisor) // only one divide for all divisors of max divisor divs := getDivisors(n) maxDiv := math.MinInt32 for _, d := range divs { if d > maxDiv { maxDiv = d } } var divsExceptMax []int for _, d := range divs { if maxDiv%d != 0 { divsExceptMax = append(divsExceptMax, d) } } // polynomial: ( x^n - 1 ) / ( x^m - 1 ), where m is the max divisor cyclo = newPoly(1, n, -1, 0) cyclo = cyclo.div(newPoly(1, maxDiv, -1, 0)) for _, i := range divsExceptMax { p := cycloPoly(i) cyclo = cyclo.div(p) } } else if algo == 2 { // fastest // let p, q be primes such that p does not divide n, and q divides n // then CP(np)[x] = CP(n)[x^p] / CP(n)[x] m := 1 cyclo = cycloPoly(m) var primes []int for prime := range factors { primes = append(primes, prime) } sort.Ints(primes) for _, prime := range primes { // CP(m)[x] cycloM := cyclo // compute CP(m)[x^p] var terms []term for _, t := range cycloM.terms { terms = append(terms, term{t.coef, t.exp * prime}) } cyclo = newPoly() cyclo.terms = append(cyclo.terms, terms...) cyclo = cyclo.tidy() cyclo = cyclo.div(cycloM) m *= prime } // now, m is the largest square free divisor of n s := n / m // Compute CP(n)[x] = CP(m)[x^s] var terms []term for _, t := range cyclo.terms { terms = append(terms, term{t.coef, t.exp * s}) } cyclo = newPoly() cyclo.terms = append(cyclo.terms, terms...) } else { log.Fatal("invalid algorithm") } cyclo = cyclo.tidy() computed[n] = cyclo return cyclo }   func main() { fmt.Println("Task 1: cyclotomic polynomials for n <= 30:") for i := 1; i <= 30; i++ { p := cycloPoly(i) fmt.Printf("CP[%2d] = %s\n", i, p) }   fmt.Println("\nTask 2: Smallest cyclotomic polynomial with n or -n as a coefficient:") n := 0 for i := 1; i <= 10; i++ { for { n++ cyclo := cycloPoly(n) if cyclo.hasCoefAbs(i) { fmt.Printf("CP[%d] has coefficient with magnitude = %d\n", n, i) n-- break } } } }
http://rosettacode.org/wiki/Cut_a_rectangle
Cut a rectangle
A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such paths for 2 × 2 and 4 × 3 rectangles are shown below. Write a program that calculates the number of different ways to cut an m × n rectangle. Optionally, show each of the cuts. Possibly related task: Maze generation for depth-first search.
#J
J
init=: - {. 1: NB. initial state: 1 square choosen prop=: < {:,~2 ~:/\ ] NB. propagate: neighboring squares (vertically) poss=: I.@,@(prop +. prop"1 +. prop&.|. +. prop&.|."1) keep=: poss -. <:@#@, - I.@, NB. symmetrically valid possibilities N=: <:@-:@#@, NB. how many neighbors to add step=: [: ~.@; <@(((= i.@$) +. ])"0 _~ keep)"2 all=: step^:N@init