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http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#Nim
Nim
import random, strutils, tables   type Choice {.pure.} = enum Rock, Paper, Scissors History = tuple[total: int; counts: CountTable[Choice]]   const Successor: array[Choice, Choice] = [Paper, Scissors, Rock]   func `>`(a, b: Choice): bool = ## By construction, only the successor is greater than the choice. a == ...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
RunLengthEncode[input_String]:= (l |-> {First@l, Length@l}) /@ (Split@Characters@input)
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#GW-BASIC
GW-BASIC
10 INPUT "Enter a string: ",A$ 20 GOSUB 50 30 PRINT B$ 40 END 50 FOR I=1 TO LEN(A$) 60 N=ASC(MID$(A$,I,1)) 70 E=255 80 IF N>64 AND N<91 THEN E=90 ' uppercase 90 IF N>96 AND N<123 THEN E=122 ' lowercase 100 IF E<255 THEN N=N+13 110 IF N>E THEN N=N-26 120 B$=B$+CHR$(N) 130 NEXT 140 RETURN
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#Raku
Raku
my @haystack = <Zig Zag Wally Ronald Bush Krusty Charlie Bush Bozo>;   for <Washington Bush> -> $needle { say "$needle -- { @haystack.first($needle, :k) // 'not in haystack' }"; }
http://rosettacode.org/wiki/Roman_numerals/Encode
Roman numerals/Encode
Task Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero. In Roman numeral...
#Elena
Elena
import system'collections; import system'routines; import extensions; import extensions'text;   static RomanDictionary = Dictionary.new() .setAt(1000, "M") .setAt(900, "CM") .setAt(500, "D") .setAt(400, "CD")...
http://rosettacode.org/wiki/Roman_numerals/Decode
Roman numerals/Decode
Task Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer. You don't need to validate the form of the Roman numeral. Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately, starting with the leftmost decima...
#F.23
F#
let decimal_of_roman roman = let rec convert arabic lastval = function | head::tail -> let n = match head with | 'M' | 'm' -> 1000 | 'D' | 'd' -> 500 | 'C' | 'c' -> 100 | 'L' | 'l' -> 50 | 'X' | '...
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#PicoLisp
PicoLisp
(de findRoots (F Start Stop Step Eps) (filter '((N) (> Eps (abs (F N)))) (range Start Stop Step) ) )   (scl 12)   (mapcar round (findRoots '((X) (+ (*/ X X X `(* 1.0 1.0)) (*/ -3 X X 1.0) (* 2 X))) -1.0 3.0 0.0001 0.00000001 ) )
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#NS-HUBASIC
NS-HUBASIC
10 COMPUTER=RND(3)+1 20 COMPUTER$="ROCK" 30 IF COMPUTER=2 THEN COMPUTER$="PAPER" 40 IF COMPUTER=3 THEN COMPUTER$="SCISSORS" 50 INPUT "ROCK, PAPER OR SCISSORS? ",HUMAN$ 60 IF HUMAN$="ROCK" THEN GOTO 100 70 IF HUMAN$="PAPER" THEN GOTO 100 80 IF HUMAN$="SCISSORS" THEN GOTO 100 90 PRINT "INVALID GUESS. TRY AGAIN.": GOTO 50...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#Maxima
Maxima
rle(a) := block( [n: slength(a), b: "", c: charat(a, 1), k: 1], for i from 2 thru n do if cequal(c, charat(a, i)) then k: k + 1 else (b: sconcat(b, k, c), c: charat(a, i), k: 1), sconcat(b, k, c) )$   rle("WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW"); "12W1B12W3B24W1B14W"
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#Haskell
Haskell
import Data.Char (chr, isAlpha, ord, toLower) import Data.Bool (bool)   rot13 :: Char -> Char rot13 c | isAlpha c = chr $ bool (-) (+) ('m' >= toLower c) (ord c) 13 | otherwise = c   -- Simple test main :: IO () main = print $ rot13 <$> "Abjurer nowhere"
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#REBOL
REBOL
rebol [ Title: "List Indexing" URL: http://rosettacode.org/wiki/Index_in_a_list ]   locate: func [ "Find the index of a string (needle) in string collection (haystack)." haystack [series!] "List of values to search." needle [string!] "String to find in value list." /largest "Return the largest index if more than ...
http://rosettacode.org/wiki/Roman_numerals/Encode
Roman numerals/Encode
Task Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero. In Roman numeral...
#Elixir
Elixir
defmodule Roman_numeral do def encode(0), do: '' def encode(x) when x >= 1000, do: [?M | encode(x - 1000)] def encode(x) when x >= 100, do: digit(div(x,100), ?C, ?D, ?M) ++ encode(rem(x,100)) def encode(x) when x >= 10, do: digit(div(x,10), ?X, ?L, ?C) ++ encode(rem(x,10)) def encode(x) when x >= 1, do:...
http://rosettacode.org/wiki/Roman_numerals/Decode
Roman numerals/Decode
Task Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer. You don't need to validate the form of the Roman numeral. Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately, starting with the leftmost decima...
#Factor
Factor
USE: roman ( scratchpad ) "MMMCCCXXXIII" roman> . 3333
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#PL.2FI
PL/I
  f: procedure (x) returns (float (18)); declare x float (18); return (x**3 - 3*x**2 + 2*x ); end f;   declare eps float, (x, y) float (18); declare dx fixed decimal (15,13);   eps = 1e-12;   do dx = -5.03 to 5 by 0.1; x = dx; if sign(f(x)) ^= sign(f(dx+0.1)) then call locate_root; end;   locate_root:...
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#OCaml
OCaml
  let pf = Printf.printf ;;   let looses a b = match a, b with `R, `P -> true | `P, `S -> true | `S, `R -> true | _, _ -> false ;;   let rec get_move () = pf "[R]ock, [P]aper, [S]cisors [Q]uit? " ; match String.uppercase (read_line ()) with "P" -> `P | "S" -> `S | "R" -> `R ...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#MMIX
MMIX
LOC Data_Segment GREG @ Buf OCTA 0,0,0,0 integer print buffer Char BYTE 0,0 single char print buffer task BYTE "WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWW" BYTE "WWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW",0 len GREG @-1-task // task should become this tEnc BYTE "12W1B12W3B24W1B14W",0   GREG @ // tuple array...
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#HicEst
HicEst
CHARACTER c, txt='abc? XYZ!', cod*100   DO i = 1, LEN_TRIM(txt) c = txt(i) n = ICHAR(txt(i)) IF( (c >= 'a') * (c <= 'm') + (c >= 'A') * (c <= 'M') ) THEN c = CHAR( ICHAR(c) + 13 ) ELSEIF( (c >= 'n') * (c <= 'z') + (c >= 'N') * (c <= 'Z') ) THEN c = CHAR( ICHAR(c) - 13 ) ENDIF   ...
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#REXX
REXX
/*REXX program searches a collection of strings (an array of periodic table elements).*/ hay.= /*initialize the haystack collection. */ hay.1 = 'sodium' hay.2 = 'phosphorous' hay.3 = 'californium' hay.4 = 'copernicium' hay.5 = 'gold' hay.6 = 'thallium' hay.7 = 'carbo...
http://rosettacode.org/wiki/Roman_numerals/Encode
Roman numerals/Encode
Task Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero. In Roman numeral...
#Emacs_Lisp
Emacs Lisp
(defun ar2ro (AN) "Translate from arabic number AN to roman number. For example, (ar2ro 1666) returns (M D C L X V I)." (cond ((>= AN 1000) (cons 'M (ar2ro (- AN 1000)))) ((>= AN 900) (cons 'C (cons 'M (ar2ro (- AN 900))))) ((>= AN 500) (cons 'D (ar2ro (- AN 500)))) ((>= AN 400) (cons 'C (cons 'D (ar...
http://rosettacode.org/wiki/Roman_numerals/Decode
Roman numerals/Decode
Task Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer. You don't need to validate the form of the Roman numeral. Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately, starting with the leftmost decima...
#FALSE
FALSE
[ 32| {get value of Roman digit on stack} $'m= $[\% 1000\]? ~[ $'d= $[\% 500\]? ~[ $'c= $[\% 100\]? ~[ $'l= $[\% 50\]? ~[ $'x= $[\% 10\]? ~[ $'v= $[\% 5\]? ~[ $'i= $[\% 1\]? ~[  % 0 ]?]?]?]?]?]?]? ]r:   0 {accumulator} ^r;! {read first Roman digit} [^r;!$][ {read another, and as l...
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#PureBasic
PureBasic
Procedure.d f(x.d) ProcedureReturn x*x*x-3*x*x+2*x EndProcedure   Procedure main() OpenConsole() Define.d StepSize= 0.001 Define.d Start=-1, stop=3 Define.d value=f(start), x=start Define.i oldsign=Sign(value)   If value=0 PrintN("Root found at "+StrF(start)) EndIf   While x<=stop value=f(x) ...
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#PARI.2FGP
PARI/GP
contest(rounds)={ my(v=[1,1,1],wins,losses); \\ Laplace rule for(i=1,rounds, my(computer,player,t); t=random(v[1]+v[2]+v[3]); if(t<v[1], computer = "R", if(t<v[1]+v[2], computer = "P", computer = "S") ); print("Rock, paper, or scissors?"); t = Str(input()); if(#t, player=Vec(...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#Nim
Nim
import parseutils, strutils   proc compress(input: string): string = var count = 1 prev = '\0'   for ch in input: if ch != prev: if prev != '\0': result.add $count & prev count = 1 prev = ch else: inc count result.add $count & prev   proc uncompress(text: string): s...
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#Icon_and_Unicon
Icon and Unicon
procedure main(arglist) file := open(arglist[1],"r") | &input every write(rot13(|read(file))) end   procedure rot13(s) #: returns rot13(string) static a,n initial { a := &lcase || &ucase (&lcase || &lcase) ? n := ( move(13), move(*&lcase) ) (&ucase || &ucase) ? n ||:= ( move(13), move(*&ucase) ) } r...
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#Ring
Ring
  haystack = ["alpha","bravo","charlie","delta","echo","foxtrot","golf", "hotel","india","juliet","kilo","lima","mike","needle", "november","oscar","papa","quebec","romeo","sierra","tango", "needle","uniform","victor","whisky","x-ray","yankee","zulu"]   needle = "needle" maxindex = len(haystack)   for index = 1 to ...
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#Ruby
Ruby
haystack = %w(Zig Zag Wally Ronald Bush Krusty Charlie Bush Bozo)   %w(Bush Washington).each do |needle| if (i = haystack.index(needle)) puts "#{i} #{needle}" else raise "#{needle} is not in haystack\n" end end
http://rosettacode.org/wiki/Roman_numerals/Encode
Roman numerals/Encode
Task Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero. In Roman numeral...
#Erlang
Erlang
-module(roman). -export([to_roman/1]).   to_roman(0) -> []; to_roman(X) when X >= 1000 -> [$M | to_roman(X - 1000)]; to_roman(X) when X >= 100 -> digit(X div 100, $C, $D, $M) ++ to_roman(X rem 100); to_roman(X) when X >= 10 -> digit(X div 10, $X, $L, $C) ++ to_roman(X rem 10); to_roman(X) when X >= 1 -> digit(X...
http://rosettacode.org/wiki/Roman_numerals/Decode
Roman numerals/Decode
Task Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer. You don't need to validate the form of the Roman numeral. Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately, starting with the leftmost decima...
#Forth
Forth
create (arabic) 1000 128 * char M + , 500 128 * char D + , 100 128 * char C + , 50 128 * char L + , 10 128 * char X + , 5 128 * char V + , 1 128 * char I + , does> 7 cells bounds do i @ over over 127 and = if nip 7 rshift leave else drop then 1 cells +loop dup ;   : >arabic 0 dup >r ...
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#Python
Python
f = lambda x: x * x * x - 3 * x * x + 2 * x   step = 0.001 # Smaller step values produce more accurate and precise results start = -1 stop = 3   sign = f(start) > 0   x = start while x <= stop: value = f(x)   if value == 0: # We hit a root print "Root found at", x elif (value > 0) != sign: ...
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#Perl
Perl
  use 5.012; use warnings; use utf8; use open qw(:encoding(utf-8) :std); use Getopt::Long;   package Game { use List::Util qw(shuffle first);   my $turns = 0; my %human_choice = ( rock => 0, paper => 0, scissors => 0, ); my %comp_choice = ( rock => 0, paper => 0, scissors => 0, ); my %what_b...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#Objeck
Objeck
use RegEx;   class RunLengthEncoding { function : Main(args : String[]) ~ Nil { input := "WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW";   encoded := Encode(input); "encoding: {$encoded}"->PrintLine(); test := encoded->Equals("12W1B12W3B24W1B14W"); "encoding match: {$test}"-...
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#IS-BASIC
IS-BASIC
100 PROGRAM "Rot13.bas" 110 DO 120 LINE INPUT PROMPT "Line: ":LINE$ 130 PRINT ROT13$(LINE$) 140 LOOP UNTIL LINE$="" 150 DEF ROT13$(TEXT$) 160 LET RESULT$="" 170 FOR I=1 TO LEN(TEXT$) 180 LET CH$=TEXT$(I) 190 SELECT CASE CH$ 200 CASE "A" TO "M","a" TO "m" 210 LET CH$=CHR$(ORD(CH$)+13) 220 C...
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#Run_BASIC
Run BASIC
haystack$ = ("Zig Zag Wally Ronald Bush Krusty Charlie Bush Bozo Bush ") needle$ = "Zag Wally Bush Chicken"   while word$(needle$,i+1," ") <> "" i = i + 1 thisNeedle$ = word$(needle$,i," ") + " " j = instr(haystack$,thisNeedle$) k1 = 0 k = instr(haystack$,thisNeedle$,j+1) while k <> 0 k1 = k k...
http://rosettacode.org/wiki/Roman_numerals/Encode
Roman numerals/Encode
Task Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero. In Roman numeral...
#ERRE
ERRE
  PROGRAM ARAB2ROMAN   DIM ARABIC%[12],ROMAN$[12]   PROCEDURE TOROMAN(VALUE->ANS$) LOCAL RESULT$ FOR I%=0 TO 12 DO WHILE VALUE>=ARABIC%[I%] DO RESULT$+=ROMAN$[I%] VALUE-=ARABIC%[I%] END WHILE END FOR ANS$=RESULT$ END PROCEDURE   BEGIN ! !Testing ! ARABIC%[]=(1000,9...
http://rosettacode.org/wiki/Roman_numerals/Decode
Roman numerals/Decode
Task Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer. You don't need to validate the form of the Roman numeral. Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately, starting with the leftmost decima...
#Fortran
Fortran
program Roman_decode implicit none   write(*,*) decode("MCMXC"), decode("MMVIII"), decode("MDCLXVI")   contains   function decode(roman) result(arabic) character(*), intent(in) :: roman integer :: i, n, lastval, arabic   arabic = 0 lastval = 0 do i = len(roman), 1, -1 select case(roman(i:i)) cas...
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#R
R
f <- function(x) x^3 -3*x^2 + 2*x   findroots <- function(f, begin, end, tol = 1e-20, step = 0.001) { se <- ifelse(sign(f(begin))==0, 1, sign(f(begin))) x <- begin while ( x <= end ) { v <- f(x) if ( abs(v) < tol ) { print(sprintf("root at %f", x)) } else if ( ifelse(sign(v)==0, 1, sign(v)) != s...
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#Phix
Phix
--standard game constant rule3 = {"rock blunts scissors", "paper wraps rock", "scissors cut paper"} --extended version constant rule5 = {"rock blunts scissors", "rock crushes lizard", "paper wraps rock", "paper disproves spock", ...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#Objective-C
Objective-C
let encode str = let len = String.length str in let rec aux i acc = if i >= len then List.rev acc else let c1 = str.[i] in let rec aux2 j = if j >= len then (c1, j-i) else let c2 = str.[j] in if c1 = c2 then aux2 (j+1) else (c1, j-i) ...
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#J
J
rot13=: {&((65 97+/~i.2 13) |.@[} i.256)&.(a.&i.)
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#Rust
Rust
fn main() { let haystack=vec!["Zig", "Zag", "Wally", "Ronald", "Bush", "Krusty", "Charlie", "Bush", "Boz", "Zag"];   println!("First occurence of 'Bush' at {:?}",haystack.iter().position(|s| *s=="Bush")); println!("Last occurence of 'Bush' at {:?}",haystack.iter().rposition(|s| *s==...
http://rosettacode.org/wiki/Roman_numerals/Encode
Roman numerals/Encode
Task Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero. In Roman numeral...
#Euphoria
Euphoria
constant arabic = {1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1 } constant roman = {"M", "CM", "D","CD", "C","XC","L","XL","X","IX","V","IV","I"}   function toRoman(integer val) sequence result result = "" for i = 1 to 13 do while val >= arabic[i] do result &= roman[i] ...
http://rosettacode.org/wiki/Roman_numerals/Decode
Roman numerals/Decode
Task Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer. You don't need to validate the form of the Roman numeral. Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately, starting with the leftmost decima...
#FreeBASIC
FreeBASIC
' FB 1.05.0 Win64   Function romanDecode(roman As Const String) As Integer If roman = "" Then Return 0 '' zero denotes invalid roman number Dim roman1(0 To 2) As String = {"MMM", "MM", "M"} Dim roman2(0 To 8) As String = {"CM", "DCCC", "DCC", "DC", "D", "CD", "CCC", "CC", "C"} Dim roman3(0 To 8) As String = {"...
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#Racket
Racket
  #lang racket   ;; Attempts to find all roots of a real-valued function f ;; in a given interval [a b] by dividing the interval into N parts ;; and using the root-finding method on each subinterval ;; which proves to contain a root. (define (find-roots f a b #:divisions [N 10] ...
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#Raku
Raku
sub f(\x) { x³ - 3*x² + 2*x }   my $start = -1; my $stop = 3; my $step = 0.001;   for $start, * + $step ... $stop -> $x { state $sign = 0; given f($x) { my $next = .sign; when 0.0 { say "Root found at $x"; } when $sign and $next != $sign { say "Root found ...
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#Phixmonti
Phixmonti
include ..\Utilitys.pmt   0 var wh 0 var wc   ( "Scissors cuts Paper" "Paper covers Rock" "Rock crushes Lizard" "Lizard poisons Spock" "Spock smashes Scissors" "Scissors decapites Lizard" "Lizard eats Paper" "Paper disproves Spock" "Spock vaporizes Rock" "Rock blunts Scissors" )   "'Rock, Pa...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#OCaml
OCaml
let encode str = let len = String.length str in let rec aux i acc = if i >= len then List.rev acc else let c1 = str.[i] in let rec aux2 j = if j >= len then (c1, j-i) else let c2 = str.[j] in if c1 = c2 then aux2 (j+1) else (c1, j-i) ...
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#Java
Java
import java.io.*;   public class Rot13 {   public static void main(String[] args) throws IOException { if (args.length >= 1) { for (String file : args) { try (InputStream in = new BufferedInputStream(new FileInputStream(file))) { rot13(in, System.out); ...
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#S-lang
S-lang
variable haystack = ["Zig","Zag","Wally","Ronald","Bush","Krusty","Charlie","Bush","Bozo","Ronald"];   define find(needle) { variable i = where(haystack == needle); if (length(i)) {  % print(sprintf("%s: first=%d, last=%d", needle, i[0], i[-1])); return(i[0], i[-1]); } else throw App...
http://rosettacode.org/wiki/Roman_numerals/Encode
Roman numerals/Encode
Task Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero. In Roman numeral...
#Excel
Excel
  =ROMAN(2013,0)  
http://rosettacode.org/wiki/Roman_numerals/Decode
Roman numerals/Decode
Task Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer. You don't need to validate the form of the Roman numeral. Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately, starting with the leftmost decima...
#FutureBasic
FutureBasic
window 1   local fn RomantoDecimal( roman as CFStringRef ) as long long i, n, preNum = 0, num = 0   for i = len(roman) - 1 to 0 step -1 n = 0 select ( fn StringCharacterAtIndex( roman, i ) ) case _"M" : n = 1000 case _"D" : n = 500 case _"C" : n = 100 case _"L" : n = 50 case _"...
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#REXX
REXX
/*REXX program finds the roots of a specific function: x^3 - 3*x^2 + 2*x via bisection*/ parse arg bot top inc . /*obtain optional arguments from the CL*/ if bot=='' | bot=="," then bot= -5 /*Not specified? Then use the default.*/ if top=='' | top=="," then top= +5 ...
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#PHP
PHP
    <?php echo "<h1>" . "Choose: ROCK - PAPER - SCISSORS" . "</h1>"; echo "<h2>"; echo "";   $player = strtoupper( $_GET["moves"] ); $wins = [ 'ROCK' => 'SCISSORS', 'PAPER' => 'ROCK', 'SCISSORS' => 'PAPER' ]; $a_i = array_rand($wins); echo "<br>"; echo "Player chooses " . "<i style=\"color:blue\">" . $pla...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#Oforth
Oforth
: encode(s) StringBuffer new s group apply(#[ tuck size asString << swap first <<c ]) ;   : decode(s) | c i | StringBuffer new 0 s forEach: c [ c isDigit ifTrue: [ 10 * c asDigit + continue ] loop: i [ c <<c ] 0 ] drop ;
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#JavaScript
JavaScript
function rot13(c) { return c.replace(/([a-m])|([n-z])/ig, function($0,$1,$2) { return String.fromCharCode($1 ? $1.charCodeAt(0) + 13 : $2 ? $2.charCodeAt(0) - 13 : 0) || $0; }); } rot13("ABJURER nowhere") // NOWHERE abjurer  
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#Sather
Sather
class MAIN is main is haystack :ARRAY{STR} := |"Zig", "Zag", "Wally", "Ronald", "Bush", "Krusty", "Charlie", "Bush", "Bozo"|; needles :ARRAY{STR} := | "Washington", "Bush" |; loop needle ::= needles.elt!; index ::= haystack.index_of(needle); if index < 0 then #OUT + needle + " is not in th...
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#Scala
Scala
def findNeedles(needle: String, haystack: Seq[String]) = haystack.zipWithIndex.filter(_._1 == needle).map(_._2) def firstNeedle(needle: String, haystack: Seq[String]) = findNeedles(needle, haystack).head def lastNeedle(needle: String, haystack: Seq[String]) = findNeedles(needle, haystack).last
http://rosettacode.org/wiki/Roman_numerals/Encode
Roman numerals/Encode
Task Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero. In Roman numeral...
#F.23
F#
let digit x y z = function 1 -> x | 2 -> x + x | 3 -> x + x + x | 4 -> x + y | 5 -> y | 6 -> y + x | 7 -> y + x + x | 8 -> y + x + x + x | 9 -> x + z | _ -> failwith "invalid call to digit"   let rec to_roman acc = function | x when x >= 1000 -> to_roman (acc + "M") (x - 1000) | x when x >...
http://rosettacode.org/wiki/Roman_numerals/Decode
Roman numerals/Decode
Task Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer. You don't need to validate the form of the Roman numeral. Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately, starting with the leftmost decima...
#Gambas
Gambas
'This code will create a GUI Form and Objects and carry out the Roman Numeral convertion as you type 'The input is case insensitive 'A basic check for invalid charaters is made   hTextBox As TextBox 'To allow the creation of a TextBox hValueBox As ValueBox ...
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#Ring
Ring
  load "stdlib.ring" function = "return pow(x,3)-3*pow(x,2)+2*x" rangemin = -1 rangemax = 3 stepsize = 0.001 accuracy = 0.1 roots(function, rangemin, rangemax, stepsize, accuracy)   func roots funct, min, max, inc, eps oldsign = 0 for x = min to max step inc num = sign(eval(funct)) if num = ...
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#Picat
Picat
go ?=> println("\nEnd terms with '.'.\n'quit.' ends the session.\n"), Prev = findall(P,beats(P,_)), ChoiceMap = new_map([P=0 : P in Prev]), ResultMap = new_map([computer_wins=0,user_wins=0,draw=0]), play(Prev,ChoiceMap,ResultMap), nl, println("Summary:"), println(choiceMap=ChoiceMap), println(resultMa...
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#PicoLisp
PicoLisp
(use (C Mine Your) (let (Rock 0 Paper 0 Scissors 0) (loop (setq Mine (let N (if (gt0 (+ Rock Paper Scissors)) (rand 1 @) 0) (seek '((L) (le0 (dec 'N (caar L)))) '(Rock Paper Scissors .) ) ) ) (prin "Enter R, P or S to play, or Q...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#Ol
Ol
  (define (RLE str) (define iter (string->list str)) (let loop ((iter iter) (chr (car iter)) (n 0) (rle '())) (cond ((null? iter) (reverse (cons (cons n chr) rle))) ((char=? chr (car iter)) (loop (cdr iter) chr (+ n 1) rle)) (else (loop (cdr ite...
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#jq
jq
#!/usr/bin/env jq -M -R -r -f # or perhaps: #!/usr/local/bin/jq -M -R -r -f   # If your operating system does not allow more than one option # to be specified on the command line, # then consider using a version of jq that allows # command-line options to be squished together (-MRrf), # or see the following subsection....
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#Scheme
Scheme
(define haystack '("Zig" "Zag" "Wally" "Ronald" "Bush" "Krusty" "Charlie" "Bush" "Bozo"))   (define index-of (lambda (needle hackstack) (let ((tail (member needle haystack))) (if tail (- (length haystack) (length tail)) (throw 'needle-missing)))))   (define last-index-of (lambda (nee...
http://rosettacode.org/wiki/Roman_numerals/Encode
Roman numerals/Encode
Task Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero. In Roman numeral...
#Factor
Factor
USE: roman ( scratchpad ) 3333 >roman . "mmmcccxxxiii"
http://rosettacode.org/wiki/Roman_numerals/Decode
Roman numerals/Decode
Task Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer. You don't need to validate the form of the Roman numeral. Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately, starting with the leftmost decima...
#Go
Go
package main   import ( "errors" "fmt" )   var m = map[rune]int{ 'I': 1, 'V': 5, 'X': 10, 'L': 50, 'C': 100, 'D': 500, 'M': 1000, }   func parseRoman(s string) (r int, err error) { if s == "" { return 0, errors.New("Empty string") } is := []rune(s) // easier to co...
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#RLaB
RLaB
  f = function(x) { rval = x .^ 3 - 3 * x .^ 2 + 2 * x; return rval; };   >> findroot(f, , [-5,5]) 0  
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#PL.2FI
PL/I
  rock: procedure options (main); /* 30 October 2013 */ declare move character (1), cm fixed binary;   put ('The Rock-Paper-Scissors game'); put skip list ("please type 'r' for rock, 'p' for paper, 's' for scissors."); put skip list ("Anything else finishes:"); do forever; get edit (move) (a(1));...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#Oz
Oz
declare fun {RLEncode Xs} for G in {Group Xs} collect:C do {C {Length G}#G.1} end end   fun {RLDecode Xs} for C#Y in Xs append:Ap do {Ap {Replicate Y C}} end end   %% Helpers %% e.g. "1122" -> ["11" "22"] fun {Group Xs} case Xs of nil then nil [] X|Xr then Ys Zs {L...
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#Jsish
Jsish
#!/usr/local/bin/jsish /* ROT-13 in Jsish */ function rot13(msg:string) { return msg.replace(/([a-m])|([n-z])/ig, function(m,p1,p2,ofs,str) { return String.fromCharCode( p1 ? p1.charCodeAt(0) + 13 : p2 ? p2.charCodeAt(0) - 13 : 0) || m; }); } provide('rot13', Util.verConvert("1.0"));   /* ro...
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#SenseTalk
SenseTalk
  put ("apple", "banana", "cranberry" ,"durian", "eggplant", "grape", "banana", "appl", "blackberry") into fruitList   put findInList(fruitList,"banana") // 2 put findInList(fruitList,"banana", true) // 7 put findInList(fruitList,"tomato") // throws an exception   function findInList paramList, paramItem, findLast ...
http://rosettacode.org/wiki/Roman_numerals/Encode
Roman numerals/Encode
Task Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero. In Roman numeral...
#FALSE
FALSE
^$." " [$999>][1000- "M"]# $899> [ 900-"CM"]? $499> [ 500- "D"]? $399> [ 400-"CD"]? [$ 99>][ 100- "C"]# $ 89> [ 90-"XC"]? $ 49> [ 50- "L"]? $ 39> [ 40-"XL"]? [$ 9>][ 10- "X"]# $ 8> [ 9-"IX"]? $ 4> [ 5- "V"]? $ 3> [ 4-"IV"]? [$ ][ 1- "I"]#%
http://rosettacode.org/wiki/Roman_numerals/Decode
Roman numerals/Decode
Task Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer. You don't need to validate the form of the Roman numeral. Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately, starting with the leftmost decima...
#Golo
Golo
#!/usr/bin/env golosh ---- This module converts a Roman numeral into a decimal number. ---- module Romannumeralsdecode   augment java.lang.Character {   function decode = |this| -> match { when this == 'I' then 1 when this == 'V' then 5 when this == 'X' then 10 when this == 'L' then 50 when this =...
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#Ruby
Ruby
def sign(x) x <=> 0 end   def find_roots(f, range, step=0.001) sign = sign(f[range.begin]) range.step(step) do |x| value = f[x] if value == 0 puts "Root found at #{x}" elsif sign(value) == -sign puts "Root found between #{x-step} and #{x}" end sign = sign(value) end end   f = lam...
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#Prolog
Prolog
play :- findall(P,beats(P,_),Prev), play(Prev).   play(Prev) :- write('your choice? '), read(P), random_member(C, Prev), format('The computer chose ~p~n', C), result(C,P,Prev,Next), !, play(Next).   result(C,P,R,[C|R]) :- beats(C,P), format('Computer wins.~n'). result(C,P,R,[B|R]) :- beats(P,C),...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#PARI.2FGP
PARI/GP
rle(s)={ if(s=="", return(s)); my(v=Vec(s),cur=v[1],ct=1,out=""); v=concat(v,99); \\ sentinel for(i=2,#v, if(v[i]==cur, ct++ , out=Str(out,ct,cur); cur=v[i]; ct=1 ) ); out }; elr(s)={ if(s=="", return(s)); my(v=Vec(s),ct=eval(v[1]),out=""); v=concat(v,99); \\ sentin...
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#Julia
Julia
  # Julia 1.0 function rot13(c::Char) shft = islowercase(c) ? 'a' : 'A' isletter(c) ? c = shft + (c - shft + 13) % 26 : c end   rot13(str::AbstractString) = map(rot13, str)
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#Sidef
Sidef
var haystack = %w(Zig Zag Wally Ronald Bush Krusty Charlie Bush Bozo);   %w(Bush Washington).each { |needle| var i = haystack.first_index{|item| item == needle}; if (i >= 0) { say "#{i} #{needle}"; } else { die "#{needle} is not in haystack"; } }
http://rosettacode.org/wiki/Roman_numerals/Encode
Roman numerals/Encode
Task Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero. In Roman numeral...
#Fan
Fan
** ** converts a number to its roman numeral representation ** class RomanNumerals {   private Str digit(Str x, Str y, Str z, Int i) { switch (i) { case 1: return x case 2: return x+x case 3: return x+x+x case 4: return x+y case 5: return y case 6: return y+x case 7...
http://rosettacode.org/wiki/Roman_numerals/Decode
Roman numerals/Decode
Task Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer. You don't need to validate the form of the Roman numeral. Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately, starting with the leftmost decima...
#Groovy
Groovy
enum RomanDigits { I(1), V(5), X(10), L(50), C(100), D(500), M(1000);   private magnitude; private RomanDigits(magnitude) { this.magnitude = magnitude }   String toString() { super.toString() + "=${magnitude}" }   static BigInteger parse(String numeral) { assert numeral != null && !numeral.e...
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#Rust
Rust
// 202100315 Rust programming solution   use roots::find_roots_cubic;   fn main() {   let roots = find_roots_cubic(1f32, -3f32, 2f32, 0f32);   println!("Result : {:?}", roots); }
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#PureBasic
PureBasic
Enumeration ;choices are in listed according to their cycle, weaker followed by stronger #rock #paper #scissors #numChoices ;this comes after all possible choices EndEnumeration   ;give names to each of the choices Dim choices.s(#numChoices - 1) choices(#rock) = "rock" choices(#paper) = "paper" choices(#sciss...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#Pascal
Pascal
Program RunLengthEncoding(output);   procedure encode(s: string; var counts: array of integer; var letters: string); var i, j: integer; begin j := 0; letters := ''; if length(s) > 0 then begin j := 1; letters := letters + s[1]; counts[1] := 1; for i := 2 to length(s) do ...
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#K
K
rot13: {a:+65 97+\:2 13#!26;_ci@[!256;a;:;|a]_ic x}   rot13 "Testing! 1 2 3" "Grfgvat! 1 2 3"
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#Slate
Slate
define: #haystack -> ('Zig,Zag,Wally,Ronald,Bush,Krusty,Charlie,Bush,Bozo' splitWith: $,). {'Washington'. 'Bush'} do: [| :needle | (haystack indexOf: needle) ifNil: [inform: word ; ' is not in the haystack'] ifNotNilDo: [| :firstIndex lastIndex | inform: word ; ' is in the haystack at index ' ; firstInd...
http://rosettacode.org/wiki/Roman_numerals/Encode
Roman numerals/Encode
Task Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero. In Roman numeral...
#Forth
Forth
: vector create ( n -- ) 0 do , loop does> ( n -- ) swap cells + @ execute ; \ these are ( numerals -- numerals ) : ,I dup c@ C, ;  : ,V dup 1 + c@ C, ;  : ,X dup 2 + c@ C, ;   \ these are ( numerals -- ) :noname ,I ,X drop ;  :noname ,V ,I ,I ,I drop ;  :noname ,V ,I ,I drop ; :noname ,V ,I dr...
http://rosettacode.org/wiki/Roman_numerals/Decode
Roman numerals/Decode
Task Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer. You don't need to validate the form of the Roman numeral. Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately, starting with the leftmost decima...
#Haskell
Haskell
  module Main where   ------------------------ -- DECODER FUNCTION -- ------------------------   decodeDigit :: Char -> Int decodeDigit 'I' = 1 decodeDigit 'V' = 5 decodeDigit 'X' = 10 decodeDigit 'L' = 50 decodeDigit 'C' = 100 decodeDigit 'D' = 500 decodeDigit 'M' = 1000 decodeDigit _ = error "invalid digit"   -- W...
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#Scala
Scala
object Roots extends App { val poly = (x: Double) => x * x * x - 3 * x * x + 2 * x   private def printRoots(f: Double => Double, lowerBound: Double, upperBound: Double, step: Double): Unit = { val y = f(lowerBound) var (ox, oy, os) =...
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#Python
Python
from random import choice   rules = {'rock': 'paper', 'scissors': 'rock', 'paper': 'scissors'} previous = ['rock', 'paper', 'scissors']   while True: human = input('\nchoose your weapon: ') computer = rules[choice(previous)] # choose the weapon which beats a randomly chosen weapon from "previous"   if huma...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#Perl
Perl
sub encode { shift =~ s/(.)\1*/length($&).$1/grse; }   sub decode { shift =~ s/(\d+)(.)/$2 x $1/grse; }
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#Kotlin
Kotlin
import java.io.*   fun String.rot13() = map { when { it.isUpperCase() -> { val x = it + 13; if (x > 'Z') x - 26 else x } it.isLowerCase() -> { val x = it + 13; if (x > 'z') x - 26 else x } else -> it } }.toCharArray()   fun InputStreamReader.println() = try { BufferedReader(this)...
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#Smalltalk
Smalltalk
| haystack | haystack := 'Zig,Zag,Wally,Ronald,Bush,Krusty,Charlie,Bush,Bozo' subStrings: $,. { 'Washington' . 'Bush' } do: [:word | |t|   ((t := haystack indexOf: word) = 0) ifTrue: [ ('%1 is not in the haystack' % { word }) displayNl ] ifFalse: [ |l| ('%1 is at ...
http://rosettacode.org/wiki/Roman_numerals/Encode
Roman numerals/Encode
Task Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero. In Roman numeral...
#Fortran
Fortran
program roman_numerals   implicit none   write (*, '(a)') roman (2009) write (*, '(a)') roman (1666) write (*, '(a)') roman (3888)   contains   function roman (n) result (r)   implicit none integer, intent (in) :: n integer, parameter :: d_max = 13 integer :: d integer :: m...
http://rosettacode.org/wiki/Roman_numerals/Decode
Roman numerals/Decode
Task Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer. You don't need to validate the form of the Roman numeral. Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately, starting with the leftmost decima...
#Icon_and_Unicon
Icon and Unicon
link numbers   procedure main() every R := "MCMXC"|"MDCLXVI"|"MMVIII" do write(R, " = ",unroman(R)) end
http://rosettacode.org/wiki/Roots_of_a_function
Roots of a function
Task Create a program that finds and outputs the roots of a given function, range and (if applicable) step width. The program should identify whether the root is exact or approximate. For this task, use:     ƒ(x)   =   x3 - 3x2 + 2x
#Sidef
Sidef
func f(x) { x*x*x - 3*x*x + 2*x }   var step = 0.001 var start = -1 var stop = 3   for x in range(start+step, stop, step) { static sign = false given (var value = f(x)) { when (0) { say "Root found at #{x}" } case (sign && ((value > 0) != sign)) { say "Root fo...
http://rosettacode.org/wiki/Rock-paper-scissors
Rock-paper-scissors
Task Implement the classic children's game Rock-paper-scissors, as well as a simple predictive   AI   (artificial intelligence)   player. Rock Paper Scissors is a two player game. Each player chooses one of rock, paper or scissors, without knowing the other player's choice. The winner is decided by a set of rules: ...
#R
R
play <- function() { bias <- c(r = 1, p = 1, s = 1) repeat { playerChoice <- readline(prompt = "Rock (r), Paper (p), Scissors (s), or Quit (q)? ") if(playerChoice == "q") break rps <- c(Rock = "r", Paper = "p", Scissors = "s") if(!playerChoice %in% rps) next compChoice <- sample(rps, 1, prob =...
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#Phix
Phix
with javascript_semantics function encode(string s) sequence r = {} if length(s) then integer ch = s[1], count = 1 for i=2 to length(s) do if s[i]!=ch then r &= {count,ch} ch = s[i] count = 1 else ...
http://rosettacode.org/wiki/Rot-13
Rot-13
Task Implement a   rot-13   function   (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment). Optionally wrap this function in a utility program   (like tr,   which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu...
#Ksh
Ksh
  #!/bin/ksh   # rot-13 function   # # Variables: # integer ROT_NUM=13 # Generalize to any ROT   string1="A2p" # Default "test" string=${1:-${string1}} # Allow command line input   typeset -a lcalph=( a b c d e f g h i j k l m n o p q r s t u v w x y z ) typeset -a ucalph=( A B C D E F G H I J K L M N O P Q R S T...
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#Standard_ML
Standard ML
fun find_index (pred, lst) = let fun loop (n, []) = NONE | loop (n, x::xs) = if pred x then SOME n else loop (n+1, xs) in loop (0, lst) end;   val haystack = ["Zig","Zag","Wally","Ronald","Bush","Krusty","Charlie","Bush","Bozo"];   app (fn needle => case find_index (f...
http://rosettacode.org/wiki/Search_a_list
Search a list
Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...
#Swift
Swift
let haystack = ["Zig","Zag","Wally","Ronald","Bush","Krusty","Charlie","Bush","Bozo"] for needle in ["Washington","Bush"] { if let index = haystack.indexOf(needle) { print("\(index) \(needle)") } else { print("\(needle) is not in haystack") } }