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http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#Lingo
Lingo
-- As for built-in power() function: -- base can be either integer or float; returns float. on pow (base, exp) if exp=0 then return 1.0 else if exp<0 then exp = -exp base = 1.0/base end if res = float(base) repeat with i = 2 to exp res = res*base end repeat return res end
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#Logo
Logo
to int_power :n :m if equal? 0 :m [output 1] if equal? 0 modulo :m 2 [output int_power :n*:n :m/2] output :n * int_power :n :m-1 end
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#Python
Python
a, b = 1, 0   if (c1 := a == 1) and (c2 := b == 3): print('a = 1 and b = 3') elif c1: print('a = 1 and b <> 3') elif c2: print('a <> 1 and b = 3') else: print('a <> 1 and b <> 3')
http://rosettacode.org/wiki/FizzBuzz
FizzBuzz
Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz     (instead of the number) ...
#SAS
SAS
data _null_; do i=1 to 100; if mod(i,15)=0 then put "FizzBuzz"; else if mod(i,5)=0 then put "Buzz"; else if mod(i,3)=0 then put "Fizz"; else put i; end; run;
http://rosettacode.org/wiki/Extensible_prime_generator
Extensible prime generator
Task Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime. The routine should demonstrably rely on either: Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In thi...
#Python
Python
islice(count(7), 0, None, 2)
http://rosettacode.org/wiki/Execute_Brain****
Execute Brain****
Execute Brain**** is an implementation of Brainf***. Other implementations of Brainf***. RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages. Below are links to each of the versions of RCBF. An implementation need only properly implement the following instructions:...
#Axe
Axe
Lbl BF r₁→P r₂→I L₁→D Fill(D,768,0)   While {P} {P}→C If C='+' {D}++ ElseIf C='-' {D}-- ElseIf C='>' D++ ElseIf C='<' D-- ElseIf C='.' Disp {D}▶Char ElseIf C=',' {I}→{D} I++ ElseIf C='['?{D}=0 NEXT(P)→P ElseIf C=']' PREV(P)→P End P++ End Return   Lbl NEXT r₁++ 1→S While S If {r₁}='[' S++...
http://rosettacode.org/wiki/Evolutionary_algorithm
Evolutionary algorithm
Starting with: The target string: "METHINKS IT IS LIKE A WEASEL". An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent). A fitness function that computes the ‘closeness’ of its argument to the target string....
#C
C
#include <stdio.h> #include <stdlib.h> #include <string.h>   const char target[] = "METHINKS IT IS LIKE A WEASEL"; const char tbl[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ ";   #define CHOICE (sizeof(tbl) - 1) #define MUTATE 15 #define COPIES 30   /* returns random integer from 0 to n - 1 */ int irand(int n) { int r, rand_max =...
http://rosettacode.org/wiki/Fibonacci_sequence
Fibonacci sequence
The Fibonacci sequence is a sequence   Fn   of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the   nth   Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...
#lambdatalk
lambdatalk
  1) basic version {def fib1 {lambda {:n} {if {< :n 3} then 1 else {+ {fib1 {- :n 1}} {fib1 {- :n 2}}} }}}   {fib1 16} -> 987 (CPU ~ 16ms) {fib1 30} = 832040 (CPU > 12000ms)   2) tail-recursive version {def fib2 {def fib2.r {lambda {:a :b :i} {if {< :i 1} then :a else {fib2.r :b {+ :a :b} ...
http://rosettacode.org/wiki/Factors_of_an_integer
Factors of an integer
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#Wortel
Wortel
@let { factors1 &n !-\%%n @to n factors_tacit @(\\%% !- @to) [[  !factors1 10  !factors_tacit 100  !factors1 720 ]] }
http://rosettacode.org/wiki/Factors_of_an_integer
Factors of an integer
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#Wren
Wren
import "/fmt" for Fmt import "/math" for Int   var a = [11, 21, 32, 45, 67, 96, 159, 723, 1024, 5673, 12345, 32767, 123459, 999997] System.print("The factors of the following numbers are:") for (e in a) System.print("%(Fmt.d(6, e)) => %(Int.divisors(e))")
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
hq9plus[program_] := Module[{accumulator = 0, bottle}, bottle[n_] := ToString[n] <> If[n == 1, " bottle", " bottles"] <> " of beer"; Do[Switch[chr, "H", Print@"hello, world", "Q", Print@program, "9", Print@StringJoin[ Table[bottle[n] <> " on the wall\n" <> bottle[n] <> "\ntake one down, ...
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#MiniScript
MiniScript
code = input("Enter HQ9+ program: ")   sing = function() for i in range(99,2) print i + " bottles of beer on the wall, " + i + " bottles of beer" print "Take one down, pass it around, " + (i-1) + " bottle" + "s"*(i>2) + " of beer on the wall" end for print "1 bottle of beer on the wall, 1 bo...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#JavaScript
JavaScript
/** * Take a ruleset and return a function which takes a string to which the rules * should be applied. * @param {string} ruleSet * @returns {function(string): string} */ const markov = ruleSet => {   /** * Split a string at an index * @param {string} s The string to split * @param {number} i The index ...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Maple
Maple
num_times:=0: baz := proc() global num_times := num_times + 1; error `if`(num_times <= 1, "U0", "U1"); end proc:   bar:=proc() baz(); end proc;   foo:=proc() local i; for i from 0 to 1 do bar(); end do; end proc;
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
foo[] := Catch[ bar[1]; bar[2]; ]   bar[i_] := baz[i];   baz[i_] := Switch[i, 1, Throw["Exception U0 in baz"];, 2, Throw["Exception U1 in baz"];]
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#MATLAB_.2F_Octave
MATLAB / Octave
function exceptionsCatchNestedCall() function foo()   try bar(1); bar(2); catch disp(lasterror); rethrow(lasterror); end   end   function bar(i) baz(i); end   function baz(i) switch i case 1 ...
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#Go
Go
package main   import "fmt"   func foo() int { fmt.Println("let's foo...") defer func() { if e := recover(); e != nil { fmt.Println("Recovered from", e) } }() var a []int a[12] = 0 fmt.Println("there's no point in going on.") panic("never reached") panic(fmt.Scan) // Can use any value, here a function! }...
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#Haskell
Haskell
do {- ... -} throwIO SomeException
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#E
E
def ls := makeCommand("ls") ls("-l")   def [results, _, _] := ls.exec(["-l"]) when (results) -> { def [exitCode, out, err] := results print(out) } catch problem { print(`failed to execute ls: $problem`) }
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Emacs_Lisp
Emacs Lisp
(shell-command "ls")
http://rosettacode.org/wiki/Factorial
Factorial
Definitions   The factorial of   0   (zero)   is defined as being   1   (unity).   The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence: n,   n-1,   n-2,   ...   1 Task Write a function to return the factorial of a number. Solutions can be iterat...
#ARM_Assembly
ARM Assembly
    /* ARM assembly Raspberry PI */ /* program factorial.s */   /* Constantes */ .equ STDOUT, 1 @ Linux output console .equ EXIT, 1 @ Linux syscall .equ WRITE, 4 @ Linux syscall   /*********************************/ /* Initialized data */ /*********************************/ .data szMe...
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#Lua
Lua
number = {}   function number.pow( a, b ) local ret = 1 if b >= 0 then for i = 1, b do ret = ret * a.val end else for i = b, -1 do ret = ret / a.val end end return ret end   function number.New( v ) local num = { val = v } local mt ...
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#Quackery
Quackery
( --------------------- version #1 --------------------- )   [ not swap not 1 << | ]'[ swap peek do ] is if2.1 ( b b --> )   [ if2.1 [ [ say "true and true" ] [ say "true and false" ] [ say "false and true" ] [ say "false and false" ] ] cr ] ...
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#R
R
  if2 <- function(condition1, condition2, both_true, first_true, second_true, both_false) { expr <- if(condition1) { if(condition2) both_true else first_true } else if(condition2) second_true else both_false eval(expr) }  
http://rosettacode.org/wiki/FizzBuzz
FizzBuzz
Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz     (instead of the number) ...
#Sather
Sather
class MAIN is main is loop i ::= 1.upto!(100); s:STR := ""; if i % 3 = 0 then s := "Fizz"; end; if i % 5 = 0 then s := s + "Buzz"; end; if s.length > 0 then #OUT + s + "\n"; else #OUT + i + "\n"; end; end; end; end;
http://rosettacode.org/wiki/Extensible_prime_generator
Extensible prime generator
Task Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime. The routine should demonstrably rely on either: Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In thi...
#Racket
Racket
#lang racket ;; Using the prime functions from: (require math/number-theory)   (displayln "Show the first twenty primes.") (next-primes 1 20)   (displayln "Show the primes between 100 and 150.") ;; Note that in each of the in-range filters I "add1" to the stop value, so that (in this case) 150 is ;; considered. I'm pre...
http://rosettacode.org/wiki/Execute_Brain****
Execute Brain****
Execute Brain**** is an implementation of Brainf***. Other implementations of Brainf***. RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages. Below are links to each of the versions of RCBF. An implementation need only properly implement the following instructions:...
#BASIC
BASIC
0 ON NOT T GOTO 20 : FOR A = T TO L : B = PEEK(S + P) : ON C%(ASC(MID$(C$, A, T))) GOSUB 1, 2, 3, 4, 5, 8, 6, 7 : NEXT A : END 1 P = P + T : ON P < E GOTO 11 : O = 1E99 2 P = P - T : ON P > M GOTO 11 : O = 1E99 3 B = B + T : B = B - (B > U) * B : GOTO 9 4 B = B - T : B = B - (B < 0) * (B - U) : GOTO 9 5 PRINT CHR$(B); ...
http://rosettacode.org/wiki/Evolutionary_algorithm
Evolutionary algorithm
Starting with: The target string: "METHINKS IT IS LIKE A WEASEL". An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent). A fitness function that computes the ‘closeness’ of its argument to the target string....
#C.23
C#
using System; using System.Collections.Generic; using System.Linq;   static class Program { static Random Rng = new Random((int)DateTime.Now.Ticks);   static char NextCharacter(this Random self) { const string AllowedChars = " ABCDEFGHIJKLMNOPQRSTUVWXYZ"; return AllowedChars[self.Next() % Allowe...
http://rosettacode.org/wiki/Fibonacci_sequence
Fibonacci sequence
The Fibonacci sequence is a sequence   Fn   of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the   nth   Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...
#Lang5
Lang5
[] '__A set : dip swap __A swap 2 compress collapse '__A set execute __A -1 extract nip ;  : nip swap drop ;  : tuck swap over ; : -rot rot rot ; : 0= 0 == ; : 1+ 1 + ; : 1- 1 - ; : sum '+ reduce ; : bi 'keep dip execute ;  : keep over 'execute dip ;   : fib dup 1 > if dup 1- fib swap 2 - fib + then ; : fib dup 1 ...
http://rosettacode.org/wiki/Factors_of_an_integer
Factors of an integer
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#X86_Assembly
X86 Assembly
  section .bss factorArr resd 250 ;big buffer against seg fault   section .text global _main _main: mov ebp, esp; for correct debugging mov eax, 0x7ffffffe ;number of which we want to know the factors, max num this program works with mov ebx, eax ;save eax mov ecx, 1 ;n, factor we test for mov ...
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Nanoquery
Nanoquery
import Nanoquery.IO   // a function to handle fatal errors def fatal_error(errtext) println "%" + errtext println "usage: " + args[1] + " [filename.cp]" exit(1) end   // a function to perform '99 bottles of beer' def bottles(n) for bottles in range(n, 1, -1) bottlestr = ""   if bottles = 1 bottlestr = "bottl...
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#NetRexx
NetRexx
  var program = "9hHqQ+" var i = 0   proc bottle(n: int): string = case n of 0: result = "No more bottles" of 1: result = "1 bottle" else: result = $n & " bottles"   proc ninetyNineBottles = for n in countdown(99, 1): echo bottle(n), " bottle of beer on the wall" echo bottle(n), " bottle o...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#jq
jq
jq -nrR --rawfile markov_rules markov_rules.txt -f program.jq markov_tests.txt
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#Julia
Julia
module MarkovAlgos   struct MarkovRule{F,T} patt::F repl::T term::Bool end   isterminating(r::MarkovRule) = r.term Base.show(io::IO, rule::MarkovRule) = print(io, rule.patt, " → ", isterminating(rule) ? "." : "", rule.repl) function Base.convert(::Type{MarkovRule}, s::AbstractString) rmatch = match(...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Nemerle
Nemerle
using System; using System.Console;   namespace NestedExceptions { public class U0 : Exception { public this() {base()} }   public class U1 : Exception { public this() {base()} }   module NestedExceptions { Foo () : void { mutable call = 0;   ...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Nim
Nim
type U0 = object of Exception type U1 = object of Exception   proc baz(i) = if i > 0: raise newException(U1, "Some error") else: raise newException(U0, "Another error")   proc bar(i) = baz(i)   proc foo() = for i in 0..1: try: bar(i) except U0: echo "Function foo caught exception U0"   foo()
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Objective-C
Objective-C
@interface U0 : NSObject { } @end @interface U1 : NSObject { } @end @implementation U0 @end @implementation U1 @end   void foo(); void bar(int i); void baz(int i);   void foo() { for (int i = 0; i <= 1; i++) { @try { bar(i); } @catch (U0 *e) { NSLog(@"Function foo caught exception U0"); } } ...
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#HolyC
HolyC
try { U8 *err = 'Error'; throw(err); // throw exception } catch { if (err == 'Error') Print("Raised 'Error'"); PutExcept; // print the exception and stack trace }
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#Icon_and_Unicon
Icon and Unicon
import Exceptions   procedure main(A) every i := !A do { case Try().call{ write(g(i)) } of { Try().catch(): { x := Try().getException() write(x.getMessage(), ":\n", x.getLocation()) } } } end   procedure g(i) if numeric(i) =...
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Erlang
Erlang
os:cmd("ls").
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#ERRE
ERRE
SHELL("DIR/W")
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Euphoria
Euphoria
-- system -- -- the simplest way -- -- system spawns a new shell so I/O redirection is possible --   system( "dir /w c:\temp\ " ) -- Microsoft --   system( "/bin/ls -l /tmp" ) -- Linux BSD OSX --   ----   -- system_exec() -- ...
http://rosettacode.org/wiki/Factorial
Factorial
Definitions   The factorial of   0   (zero)   is defined as being   1   (unity).   The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence: n,   n-1,   n-2,   ...   1 Task Write a function to return the factorial of a number. Solutions can be iterat...
#ArnoldC
ArnoldC
LISTEN TO ME VERY CAREFULLY factorial I NEED YOUR CLOTHES YOUR BOOTS AND YOUR MOTORCYCLE n GIVE THESE PEOPLE AIR BECAUSE I'M GOING TO SAY PLEASE n BULLS*** I'LL BE BACK 1 YOU HAVE NO RESPECT FOR LOGIC HEY CHRISTMAS TREE product YOU SET US UP @NO PROBLEMO STICK AROUND n GET TO THE CHOPPER product HERE IS MY INVITATION p...
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#Lucid
Lucid
pow(n,x) k = n fby k div 2; p = x fby p*p; y =1 fby if even(k) then y else y*p; result y asa k eq 0; end
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#M2000_Interpreter
M2000 Interpreter
  Module Exponentiation { \\ a variable can be any type except a string (no $ in name) \\ variable b is long type. \\ by default we pass by value arguments to a function \\ to pass by reference we have to use & before name, \\ in the signature and in the call function pow(a, b as long) { p=a-a ' make p same ...
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#Racket
Racket
  #lang racket ;; define a new syntax (define-syntax-rule  ;; this is the new syntax we want, in sexpr syntax: (if2 condition1isTrue condition2isTrue bothConditionsAreTrue firstConditionIsTrue secondConditionIsTrue noConditionIsTrue)  ;; and this is the syntax that implements it: (if c...
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#Raku
Raku
my &if2 = -> \a, \b, &x { my @*IF2 = ?a,?b; x }   my &if-both = -> &x { x if @*IF2 eq (True,True) } my &if-first = -> &x { x if @*IF2 eq (True,False) } my &if-second = -> &x { x if @*IF2 eq (False,True) } my &if-neither = -> &x { x if @*IF2 eq (False,False)}   sub test ($a,$b) { $_ = "G"; # Demo co...
http://rosettacode.org/wiki/FizzBuzz
FizzBuzz
Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz     (instead of the number) ...
#Scala
Scala
object FizzBuzz extends App { 1 to 100 foreach { n => println((n % 3, n % 5) match { case (0, 0) => "FizzBuzz" case (0, _) => "Fizz" case (_, 0) => "Buzz" case _ => n }) } }
http://rosettacode.org/wiki/Extensible_prime_generator
Extensible prime generator
Task Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime. The routine should demonstrably rely on either: Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In thi...
#Raku
Raku
my @primes = lazy gather for 1 .. * { .take if .is-prime }   say "The first twenty primes:\n ", "[{@primes[^20].fmt("%d", ', ')}]"; say "The primes between 100 and 150:\n ", "[{@primes.&between(100, 150).fmt("%d", ', ')}]"; say "The number of primes between 7,700 and 8,000:\n ", +@primes.&between(7700, 8000); say...
http://rosettacode.org/wiki/Execute_Brain****
Execute Brain****
Execute Brain**** is an implementation of Brainf***. Other implementations of Brainf***. RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages. Below are links to each of the versions of RCBF. An implementation need only properly implement the following instructions:...
#BBC_BASIC
BBC BASIC
bf$ = "++++++++[>++++[>++>+++>+++>+<<<<-]>+>->+>>+[<]<-]>>.>" + \ \ ">---.+++++++..+++.>.<<-.>.+++.------.--------.>+.>++.+++." PROCbrainfuck(bf$) END   DEF PROCbrainfuck(b$) LOCAL B%, K%, M%, P% DIM M% LOCAL 65535 B% = 1 : REM pointer to string K% = 0 : REM bra...
http://rosettacode.org/wiki/Evolutionary_algorithm
Evolutionary algorithm
Starting with: The target string: "METHINKS IT IS LIKE A WEASEL". An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent). A fitness function that computes the ‘closeness’ of its argument to the target string....
#C.2B.2B
C++
#include <string> #include <cstdlib> #include <iostream> #include <cassert> #include <algorithm> #include <vector> #include <ctime>   std::string allowed_chars = " ABCDEFGHIJKLMNOPQRSTUVWXYZ";   // class selection contains the fitness function, encapsulates the // target string and allows access to it's length. The cla...
http://rosettacode.org/wiki/Fibonacci_sequence
Fibonacci sequence
The Fibonacci sequence is a sequence   Fn   of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the   nth   Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...
#langur
langur
val .fibonacci = f if(.x < 2: .x ; self(.x - 1) + self(.x - 2))   writeln map .fibonacci, series 2..20
http://rosettacode.org/wiki/Factors_of_an_integer
Factors of an integer
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#XPL0
XPL0
include c:\cxpl\codes; int N0, N, F; [N0:= 1; repeat IntOut(0, N0); Text(0, " = "); F:= 2; N:= N0; repeat if rem(N/F) = 0 then [if N # N0 then Text(0, " * "); IntOut(0, F); N:= N/F; ] ...
http://rosettacode.org/wiki/Factors_of_an_integer
Factors of an integer
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#Yabasic
Yabasic
  sub printFactors(n) if n < 1 then return 0 : fi print n, " =>", for i = 1 to n / 2 if mod(n, i) = 0 then print i, " "; : fi next i print n end sub   printFactors(11) printFactors(21) printFactors(32) printFactors(45) printFactors(67) printFactors(96) print end  
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Nim
Nim
  var program = "9hHqQ+" var i = 0   proc bottle(n: int): string = case n of 0: result = "No more bottles" of 1: result = "1 bottle" else: result = $n & " bottles"   proc ninetyNineBottles = for n in countdown(99, 1): echo bottle(n), " bottle of beer on the wall" echo bottle(n), " bottle o...
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#NS-HUBASIC
NS-HUBASIC
10 INPUT "INPUT HQ9+ CODE: ",I$ 20 B$="S" 30 W$=" ON THE WALL" 40 FOR I=1 TO LEN(I$) 50 C$=MID$(I$,I,1) 60 IF C$="H" THEN PRINT "HELLO, WORLD!" 70 IF C$="Q" THEN PRINT I$ 80 A=A+(C$="+") 90 IF C$<>"9" GOTO 200 100 FOR B=99 TO 1 STEP -1 110 IF B=1 THEN B$="" 120 PRINT B " BOTTLE"B$" OF BEER" W$ 130 PRINT B " BOTTLE"B$" ...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#Kotlin
Kotlin
// version 1.1.51   import java.io.File import java.util.regex.Pattern   /* rulesets assumed to be separated by a blank line in file */ fun readRules(path: String): List<List<String>> { val ls = System.lineSeparator() return File(path).readText().split("$ls$ls").map { it.split(ls) } }   /* tests assumed to be o...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#OCaml
OCaml
exception U0 exception U1   let baz i = raise (if i = 0 then U0 else U1)   let bar i = baz i (* Nest those calls *)   let foo () = for i = 0 to 1 do try bar i with U0 -> print_endline "Function foo caught exception U0" done   let () = foo ()
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Oforth
Oforth
Exception Class new: U0 Exception Class new: U1   : baz ifZero: [ "First call" U0 throw ] else: [ "Second call" U1 throw ] ; : bar baz ;   : foo | e | try: e [ 0 bar ] when: [ e isKindOf(U0) ifTrue: [ "Catched" .cr ] else: [ e throw ] ] try: e [ 1 bar ] when: [ e isKindOf(U0) ifTrue: [ "Catched" .cr ] else: [ e...
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#J
J
pickyPicky =: verb define if. y-:'bad argument' do. throw. else. 'thanks!' end. )   tryThis =: verb define try. pickyPicky y catcht. 'Uh oh!' end. )   tryThis 'bad argument' Uh oh!
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#Java
Java
//Checked exception public class MyException extends Exception { //Put specific info in here }   //Unchecked exception public class MyRuntimeException extends RuntimeException {}
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#F.23
F#
System.Diagnostics.Process.Start("cmd", "/c dir")
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Factor
Factor
"ls" run-process wait-for-process
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Fantom
Fantom
  class Main { public static Void main () { p := Process (["ls"]) p.run } }  
http://rosettacode.org/wiki/Factorial
Factorial
Definitions   The factorial of   0   (zero)   is defined as being   1   (unity).   The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence: n,   n-1,   n-2,   ...   1 Task Write a function to return the factorial of a number. Solutions can be iterat...
#Arturo
Arturo
factorial: $[n][ if? n>0 [n * factorial n-1] else [1] ]
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#M4
M4
define(`power',`ifelse($2,0,1,`eval($1*$0($1,decr($2)))')') power(2,10)
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
exponentiation[x_,y_Integer]:=Which[y>0,Times@@ConstantArray[x,y],y==0,1,y<0,1/exponentiation[x,-y]] CirclePlus[x_,y_Integer]:=exponentiation[x,y]
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#REXX
REXX
if2( some-expression-that-results-in-a-boolean-value, some-other-expression-that-results-in-a-boolean-value)     /*this part is a REXX comment*/ /*could be a DO structure.*/ select /*↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓*/ /*↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓*/   when if.11 /*{condition 1 &...
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#Ring
Ring
  # Project : Extend your language   see "a = 1, b = 1 => " test(1, 1) see "a = 1, b = 0 => " test(1, 0) see "a = 0, b = 1 => " test(0, 1) see "a = 0, b = 0 => " test(0, 0) see nl   func test(a,b) if a > 0 and b > 0 see "both positive" but a > 0 see "first positive" but b >...
http://rosettacode.org/wiki/FizzBuzz
FizzBuzz
Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz     (instead of the number) ...
#Scheme
Scheme
(do ((i 1 (+ i 1))) ((> i 100)) (display (cond ((= 0 (modulo i 15)) "FizzBuzz") ((= 0 (modulo i 3)) "Fizz") ((= 0 (modulo i 5)) "Buzz") (else i))) (newline))
http://rosettacode.org/wiki/Extensible_prime_generator
Extensible prime generator
Task Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime. The routine should demonstrably rely on either: Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In thi...
#Red
Red
  Red [Description: "Prime checker/generator/counter"]   context [ poke noprime: make bitset! 3 1 true top: 2   noprimes: function [n [integer!] /extern top][ either top < n [ n: n + 100 r: 2 while [r * r <= n][ repeat q n / r - 1 [poke noprime q ...
http://rosettacode.org/wiki/Execute_Brain****
Execute Brain****
Execute Brain**** is an implementation of Brainf***. Other implementations of Brainf***. RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages. Below are links to each of the versions of RCBF. An implementation need only properly implement the following instructions:...
#BCPL
BCPL
get "libhdr"   manifest $( bfeof = 0 $)   let reads(v) be $( let ch = ? v%0 := 0 ch := rdch() until ch = '*N' do $( v%0 := v%0 + 1 v%(v%0) := ch ch := rdch() $) $)   let contains(str, ch) = valof $( for i = 1 to str%0 do if ch = str%i then resultis true resultis false...
http://rosettacode.org/wiki/Evolutionary_algorithm
Evolutionary algorithm
Starting with: The target string: "METHINKS IT IS LIKE A WEASEL". An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent). A fitness function that computes the ‘closeness’ of its argument to the target string....
#Ceylon
Ceylon
import ceylon.random {   DefaultRandom }   shared void run() {   value mutationRate = 0.05; value childrenPerGeneration = 100; value target = "METHINKS IT IS LIKE A WEASEL"; value alphabet = {' ', *('A'..'Z')}; value random = DefaultRandom();   value randomLetter => random.nextElement(alphabet);   function fitn...
http://rosettacode.org/wiki/Fibonacci_sequence
Fibonacci sequence
The Fibonacci sequence is a sequence   Fn   of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the   nth   Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...
#Lasso
Lasso
  define fibonacci(n::integer) => {   #n < 1 ? return false   local( swap = 0, n1 = 0, n2 = 1 )   loop(#n) => { #swap = #n1 + #n2; #n2 = #n1; #n1 = #swap; } return #n1   }   fibonacci(0) //->output false fibonacci(1) //->output 1 fibonacci(2) //->output 1 fibonacci(3) //->output 2 ...
http://rosettacode.org/wiki/Factors_of_an_integer
Factors of an integer
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#zkl
zkl
fcn f(n){ (1).pump(n.toFloat().sqrt(), List, 'wrap(m){((n % m)==0) and T(m,n/m) or Void.Skip}) } fcn g(n){ [[(m); [1..n.toFloat().sqrt()],'{n%m==0}; '{T(m,n/m)} ]] } // list comprehension
http://rosettacode.org/wiki/Factors_of_an_integer
Factors of an integer
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#ZX_Spectrum_Basic
ZX Spectrum Basic
10 INPUT "Enter a number or 0 to exit: ";n 20 IF n=0 THEN STOP 30 PRINT "Factors of ";n;": "; 40 FOR i=1 TO n 50 IF FN m(n,i)=0 THEN PRINT i;" "; 60 NEXT i 70 DEF FN m(a,b)=a-INT (a/b)*b
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#OCaml
OCaml
let hq9p line = let accumulator = ref 0 in for i = 0 to (String.length line - 1) do match line.[i] with | 'h' | 'H' -> print_endline "Hello, world!" | 'q' | 'Q' -> print_endline line | '9' -> beer 99 | '+' -> incr accumulator done
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#PARI.2FGP
PARI/GP
beer(n)={ if(n == 1, print("1 bottle of beer on the wall"); print("1 bottle of beer"); print("Take one down and pass it around"); print("No bottles of beer on the wall") , print(n" bottles of beer on the wall"); print(n" bottles of beer"); print("Take one down and pass it around"); p...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#Lua
Lua
-- utility method to escape punctuation function normalize(str) local result = str:gsub("(%p)", "%%%1") -- print(result) return result end   -- utility method to split string into lines function get_lines(str) local t = {} for line in str:gmatch("([^\n\r]*)[\n\r]*") do table.insert(t, line) ...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Oz
Oz
declare proc {Foo} for I in 1..2 do try {Bar I} catch u0 then {System.showInfo "Procedure Foo caught exception u0"} end end end   proc {Bar I} {Baz I} end   proc {Baz I} if I == 1 then raise u0 end else raise u1 end end end in {Foo}
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#PARI.2FGP
PARI/GP
call = 0;   U0() = error("x = ", 1, " should not happen!"); U1() = error("x = ", 2, " should not happen!"); baz(x) = if(x==1, U0(), x==2, U1());x; bar() = baz(call++); foo() = if(!call, iferr(bar(), E, printf("Caught exception, call=%d",call)), bar())
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#JavaScript
JavaScript
function doStuff() { throw new Error('Not implemented!'); }
http://rosettacode.org/wiki/Exceptions
Exceptions
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops This task is to give an example of an exception handling routine and to "throw" a new exception. Related task   Exceptions Through Nested Calls
#jq
jq
try FILTER catch CATCHER
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Forth
Forth
s" ls" system
http://rosettacode.org/wiki/Execute_a_system_command
Execute a system command
Task Run either the   ls   system command   (dir   on Windows),   or the   pause   system command. Related task Get system command output
#Fortran
Fortran
  program SystemTest integer :: i call execute_command_line ("ls", exitstat=i) end program SystemTest  
http://rosettacode.org/wiki/Factorial
Factorial
Definitions   The factorial of   0   (zero)   is defined as being   1   (unity).   The   Factorial Function   of a positive integer,   n,   is defined as the product of the sequence: n,   n-1,   n-2,   ...   1 Task Write a function to return the factorial of a number. Solutions can be iterat...
#AsciiDots
AsciiDots
  /---------*--~-$#-& | /--;---\| [!]-\ | *------++--*#1/ | | /1#\ || [*]*{-}-*~<+*?#-. *-------+-</ \-#0----/  
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#Maxima
Maxima
"^^^"(a, n) := block( [p: 1], while n > 0 do ( if oddp(n) then p: p * a, a: a * a, n: quotient(n, 2) ), p )$   infix("^^^")$   2 ^^^ 10; 1024   2.5 ^^^ 10; 9536.7431640625
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#.D0.9C.D0.9A-61.2F52
МК-61/52
С/П x^y С/П
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#Ruby
Ruby
# Define a class which always returns itself for everything class HopelesslyEgocentric def method_missing(what, *args) self end end   def if2(cond1, cond2) if cond1 and cond2 yield HopelesslyEgocentric.new elsif cond1 Class.new(HopelesslyEgocentric) do def else1; yield; HopelesslyEgocentric.new ...
http://rosettacode.org/wiki/Extend_your_language
Extend your language
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua...
#Rust
Rust
#![allow(unused_variables)] macro_rules! if2 { ($cond1: expr, $cond2: expr => $both:expr => $first: expr => $second:expr => $none:expr) => { match ($cond1, $cond2) { (true, true) => $both, (true, _ ) => $first, (_ , true) => $s...
http://rosettacode.org/wiki/FizzBuzz
FizzBuzz
Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz     (instead of the number) ...
#Sed
Sed
#n # doesn't work if there's no input # initialize counters (0 = empty) and value s/.*/ 0/ : loop # increment counters, set carry s/^\(a*\) \(b*\) \([0-9][0-9]*\)/\1a \2b \3@/ # propagate carry : carry s/ @/ 1/ s/9@/@0/ s/8@/9/ s/7@/8/ s/6@/7/ s/5@/6/ s/4@/5/ s/3@/4/ s/2@/3/ s/1@/2/ s/0@/1/ /@/b carry # save state h #...
http://rosettacode.org/wiki/Extensible_prime_generator
Extensible prime generator
Task Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime. The routine should demonstrably rely on either: Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In thi...
#REXX
REXX
/*REXX program calculates and displays primes using an extendible prime number generator*/ parse arg f .; if f=='' then f= 20 /*allow specifying number for 1 ──► F.*/ _i= ' (inclusive) '; _b= 'between '; _tnp= 'the number of primes' _b; _tn= 'the primes' call primes f; do j=1 for f; $= $ @....
http://rosettacode.org/wiki/Execute_Brain****
Execute Brain****
Execute Brain**** is an implementation of Brainf***. Other implementations of Brainf***. RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages. Below are links to each of the versions of RCBF. An implementation need only properly implement the following instructions:...
#Brainf.2A.2A.2A
Brainf***
  >>>,[->+>+<<]>>[-<<+>>]>++++[<++++++++>-]<+<[->>+>>+<<<<]>>>>[-<<<<+>> >>]<<<[->>+>+<<<]>>>[-<<<+>>>]<<[>[->+<]<[-]]>[-]>[[-]<<<<->-<[->>+>>+ <<<<]>>>>[-<<<<+>>>>]<<<[->>+>+<<<]>>>[-<<<+>>>]<<[>[->+<]<[-]]>[-]>]< <<<[->>+<<]>[->+<]>[[-]<<<[->+>+<<]>>[-<<+>>]>++++++[<+++++++>-]<+<[-> >>+>+<<<<]>>>>[-<<<<+>>>>]<<<[->+>...
http://rosettacode.org/wiki/Evolutionary_algorithm
Evolutionary algorithm
Starting with: The target string: "METHINKS IT IS LIKE A WEASEL". An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent). A fitness function that computes the ‘closeness’ of its argument to the target string....
#Clojure
Clojure
(def c 100) ;number of children in each generation (def p 0.05) ;mutation probability   (def target "METHINKS IT IS LIKE A WEASEL") (def tsize (count target))   (def alphabet " ABCDEFGHIJLKLMNOPQRSTUVWXYZ")
http://rosettacode.org/wiki/Fibonacci_sequence
Fibonacci sequence
The Fibonacci sequence is a sequence   Fn   of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the   nth   Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...
#Latitude
Latitude
fibo := { takes '[n]. if { n <= 1. } then { n. } else { fibo (n - 1) + fibo (n - 2). }. }.
http://rosettacode.org/wiki/Execute_HQ9%2B
Execute HQ9+
Task Implement a   HQ9+   interpreter or compiler.
#Pascal
Pascal
program HQ9;   procedure runCode(code: string); var c_len, i, bottles: Integer; accumulator: Cardinal; begin c_len := Length(code); accumulator := 0; for i := 1 to c_len do begin case code[i] of 'Q','q': writeln(code); 'H','h': Writeln('Hello, world!'); '9': beg...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
markov[ruleset_, text_] := Module[{terminating = False, output = text, rules = StringCases[ ruleset, {StartOfLine ~~ pattern : Except["\n"] .. ~~ " " | "\t" .. ~~ "->" ~~ " " | "\t" .. ~~ dot : "" | "." ~~ replacement : Except["\n"] .. ~~ EndOfLine :> {pattern, replacement, d...
http://rosettacode.org/wiki/Execute_a_Markov_algorithm
Execute a Markov algorithm
Execute a Markov algorithm You are encouraged to solve this task according to the task description, using any language you may know. Task Create an interpreter for a Markov Algorithm. Rules have the syntax: <ruleset> ::= ((<comment> | <rule>) <newline>+)* <comment> ::= # {<any character>} <rule> ::= <pattern> <wh...
#.D0.9C.D0.9A-61.2F52
МК-61/52
9 П4 КИП4 [x] П7 Вx {x} П8 ИП8 ИПE * П8 {x} x=0 08 П5 ИП9 П1 lg [x] 10^x П3 ИП1 П2 Сx П6 ИП2 ИП7 - x=0 70 ИП9 ^ lg [x] 1 + ИП5 - 10^x / [x] ИП6 ИП8 x#0 50 lg [x] 1 + + 10^x * ИП9 ИП6 10^...
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Pascal
Pascal
sub foo { foreach (0..1) { eval { bar($_) }; if ($@ =~ /U0/) { print "Function foo caught exception U0\n"; } else { die; } # propagate the exception } }   sub bar { baz(@_); # Nest those calls }   sub baz { my $i = shift; die ($i ? "U1" : "U0"); }   foo();
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call
Exceptions/Catch an exception thrown in a nested call
Show how to create a user-defined exception   and   show how to catch an exception raised from several nested calls away.   Create two user-defined exceptions,   U0   and   U1.   Have function   foo   call function   bar   twice.   Have function   bar   call function   baz.   Arrange for function   baz   to rais...
#Perl
Perl
sub foo { foreach (0..1) { eval { bar($_) }; if ($@ =~ /U0/) { print "Function foo caught exception U0\n"; } else { die; } # propagate the exception } }   sub bar { baz(@_); # Nest those calls }   sub baz { my $i = shift; die ($i ? "U1" : "U0"); }   foo();