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http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#F.23
F#
Microsoft F# Interactive, (c) Microsoft Corporation, All Rights Reserved F# Version 1.9.6.2, compiling for .NET Framework Version v2.0.50727   Please send bug reports to fsbugs@microsoft.com For help type #help;;   > let f a b sep = String.concat sep [a; ""; b] ;;   val f : string -> string -> string -> string   > f "R...
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#Factor
Factor
./factor -run=listener
http://rosettacode.org/wiki/ISBN13_check_digit
ISBN13 check digit
Task Validate the check digit of an ISBN-13 code:   Multiply every other digit by  3.   Add these numbers and the other digits.   Take the remainder of this number after division by  10.   If it is  0,   the ISBN-13 check digit is correct. Use the following codes for testing:   978-1734314502       (good)   ...
#IS-BASIC
IS-BASIC
100 PROGRAM "ISBN13.bas" 110 DO 120 PRINT :INPUT PROMPT "ISBN-13 code: ":IS$ 130 IF IS$="" THEN EXIT DO 140 IF ISBN(IS$) THEN 150 PRINT "Ok." 160 ELSE 170 PRINT "CRC error." 180 END IF 190 LOOP 200 DEF TRIM$(S$) 210 LET T$="" 220 FOR I=1 TO LEN(S$) 230 IF S$(I)>CHR$(47) AND S$(I)<CHR$(58) THEN...
http://rosettacode.org/wiki/ISBN13_check_digit
ISBN13 check digit
Task Validate the check digit of an ISBN-13 code:   Multiply every other digit by  3.   Add these numbers and the other digits.   Take the remainder of this number after division by  10.   If it is  0,   the ISBN-13 check digit is correct. Use the following codes for testing:   978-1734314502       (good)   ...
#J
J
D =: '0123456789'   isbn13c =: D&([ check@:i. clean) check =: 0 = 10 | lc lc =: [ +/@:* weight weight =: 1 3 $~ # clean =: ] -. a. -. [
http://rosettacode.org/wiki/Jaro_similarity
Jaro similarity
The Jaro distance is a measure of edit distance between two strings; its inverse, called the Jaro similarity, is a measure of two strings' similarity: the higher the value, the more similar the strings are. The score is normalized such that   0   equates to no similarities and   1   is an exact match. Definition The...
#Nim
Nim
import lenientops   func jaro(s1, s2: string): float =   if s1.len == 0 and s2.len == 0: return 1 if s1.len == 0 or s2.len == 0: return 0   let matchDistance = max(s1.len, s2.len) div 2 - 1 var s1Matches = newSeq[bool](s1.len) var s2Matches = newSeq[bool](s2.len) var matches = 0 for i in 0..s1.high: f...
http://rosettacode.org/wiki/Jaro_similarity
Jaro similarity
The Jaro distance is a measure of edit distance between two strings; its inverse, called the Jaro similarity, is a measure of two strings' similarity: the higher the value, the more similar the strings are. The score is normalized such that   0   equates to no similarities and   1   is an exact match. Definition The...
#Objeck
Objeck
class JaroDistance { function : Main(args : String[]) ~ Nil { Jaro("MARTHA", "MARHTA")->PrintLine(); Jaro("DIXON", "DICKSONX")->PrintLine(); Jaro("JELLYFISH", "SMELLYFISH")->PrintLine(); }   function : Jaro(s : String, t : String) ~ Float { s_len := s->Size(); t_len := t->Size();   if (s_...
http://rosettacode.org/wiki/Iterated_digits_squaring
Iterated digits squaring
If you add the square of the digits of a Natural number (an integer bigger than zero), you always end with either 1 or 89: 15 -> 26 -> 40 -> 16 -> 37 -> 58 -> 89 7 -> 49 -> 97 -> 130 -> 10 -> 1 An example in Python: >>> step = lambda x: sum(int(d) ** 2 for d in str(x)) >>> iterate = lambda x: x if x in [1, 89] else i...
#Lua
Lua
squares = {}   for i = 0, 9 do for j = 0, 9 do squares[i * 10 + j] = i * i + j * j end end   for i = 1, 99 do for j = 0, 99 do squares[i * 100 + j] = squares[i] + squares[j] end end   function sum_squares(n) if n < 9999.5 then return squares[n] else local m = math...
http://rosettacode.org/wiki/Integer_sequence
Integer sequence
Task Create a program that, when run, would display all integers from   1   to   ∞   (or any relevant implementation limit),   in sequence   (i.e.   1, 2, 3, 4, etc)   if given enough time. An example may not be able to reach arbitrarily-large numbers based on implementations limits.   For example, if integer...
#Ada
Ada
with Ada.Text_IO; procedure Integers is Value : Integer := 1; begin loop Ada.Text_IO.Put_Line (Integer'Image (Value)); Value := Value + 1; -- raises exception Constraint_Error on overflow end loop; end Integers;
http://rosettacode.org/wiki/Integer_sequence
Integer sequence
Task Create a program that, when run, would display all integers from   1   to   ∞   (or any relevant implementation limit),   in sequence   (i.e.   1, 2, 3, 4, etc)   if given enough time. An example may not be able to reach arbitrarily-large numbers based on implementations limits.   For example, if integer...
#ALGOL_68
ALGOL 68
main: ( FOR i DO printf(($g(0)","$,i)) OD )
http://rosettacode.org/wiki/Integer_overflow
Integer overflow
Some languages support one or more integer types of the underlying processor. This integer types have fixed size;   usually   8-bit,   16-bit,   32-bit,   or   64-bit. The integers supported by such a type can be   signed   or   unsigned. Arithmetic for machine level integers can often be done by single CPU instruct...
#Axe
Axe
Disp -65535▶Dec,i Disp 40000+40000▶Dec,i Disp 32767-65535▶Dec,i Disp 257*257▶Dec,i
http://rosettacode.org/wiki/Integer_overflow
Integer overflow
Some languages support one or more integer types of the underlying processor. This integer types have fixed size;   usually   8-bit,   16-bit,   32-bit,   or   64-bit. The integers supported by such a type can be   signed   or   unsigned. Arithmetic for machine level integers can often be done by single CPU instruct...
#Befunge
Befunge
"a9jc>"*:*+*+:0\- "(-",,:.048*"="99")1 -" >:#,_$v v,,,9"="*84 .: ,,"+"*84 .: **:*" }}" ,+55 .-\0-1< >:+. 55+, ::0\- :. 48*"-",, \:. 48*"="9,,, -. 55v v.*: ,,,,,999"="*84 .: ,,"*"*84 .: *+8*7"s9" ,+< >55+, 0\- "(",:.048*"="99"1-/)1 -">:#,_$ 1-01-/.@
http://rosettacode.org/wiki/Isqrt_(integer_square_root)_of_X
Isqrt (integer square root) of X
Sometimes a function is needed to find the integer square root of   X,   where   X   can be a real non─negative number. Often   X   is actually a non─negative integer. For the purposes of this task,   X   can be an integer or a real number,   but if it simplifies things in your computer programming language,   assume...
#Icon
Icon
link numbers # For the "commas" procedure. link printf   procedure main () write ("isqrt(i) for 0 <= i <= 65:") write () roots_of_0_to_65() write () write () write ("isqrt(7**i) for 1 <= i <= 73, i odd:") write () printf ("%2s %84s %43s\n", "i", "7**i", "sqrt(7**i)") write (repl("-"...
http://rosettacode.org/wiki/Inverted_index
Inverted index
An Inverted Index is a data structure used to create full text search. Task Given a set of text files, implement a program to create an inverted index. Also create a user interface to do a search using that inverted index which returns a list of files that contain the query term / terms. The search index can be i...
#C.2B.2B
C++
  #include <algorithm> #include <fstream> #include <iostream> #include <vector> #include <string>   const std::string _CHARS = "abcdefghijklmnopqrstuvwxyz0123456789.:-_/"; const size_t MAX_NODES = 41;   class node { public: node() { clear(); } node( char z ) { clear(); } ~node() { for( int x = 0; x < MAX_NO...
http://rosettacode.org/wiki/Introspection
Introspection
Task verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old. check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop). Extra credit Repor...
#Common_Lisp
Common Lisp
(let* ((ver (lisp-implementation-version)) (major (parse-integer ver :start 0 :end (position #\. ver)))) #+lispworks (assert (>= 5 major) () "Requires Lispworks version 5 or above") #+clisp (assert (>= 2 major) () "Requires CLISP 2.n") )
http://rosettacode.org/wiki/Introspection
Introspection
Task verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old. check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop). Extra credit Repor...
#D
D
// Some module-level variables (D doesn't have a global scope). immutable x = 3, y = 100, z = 3_000; short w = 1; // Not an int, must be ignored. immutable s = "some string"; // Not an int, must be ignored.   void main() { import std.compiler, std.math, std.traits;   // Compile-time constants of the compiler ve...
http://rosettacode.org/wiki/Josephus_problem
Josephus problem
Josephus problem is a math puzzle with a grim description: n {\displaystyle n} prisoners are standing on a circle, sequentially numbered from 0 {\displaystyle 0} to n − 1 {\displaystyle n-1} . An executioner walks along the circle, starting from prisoner 0 {\displaystyle 0} , removing eve...
#friendly_interactive_shell
friendly interactive shell
function execute # If the list is empty, don't do anything. test (count $argv) -ge 2; or return # If the list has only one element, return it if test (count $argv) -eq 2 echo $argv[2] return end # Rotate prisoners for i in (seq 2 $argv[1]) set argv $argv[1 3..-1 2] ...
http://rosettacode.org/wiki/Intersecting_number_wheels
Intersecting number wheels
A number wheel has: A name which is an uppercase letter. A set of ordered values which are either numbers or names. A number is generated/yielded from a named wheel by: 1. Starting at the first value of the named wheel and advancing through subsequent values and wrapping around to the first value to form a "wheel"...
#Java
Java
  package intersectingNumberWheels; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.stream.IntStream;   public class WheelController { private static final String IS_NUMBER = "[0-9]"; private static final int TWENTY = 20; private static Map<String, ...
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#Fantom
Fantom
$ fansh Fantom Shell v1.0.57 ('?' for help) fansh> f := |Str a, Str b, Str c -> Str| {"$a$c$c$b"} |sys::Str,sys::Str,sys::Str->sys::Str| fansh> f("Rosetta", "Code", ":") Rosetta::Code
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#Forth
Forth
$ gforth Gforth 0.7.0, Copyright (C) 1995-2008 Free Software Foundation, Inc. Gforth comes with ABSOLUTELY NO WARRANTY; for details type `license' Type `bye' to exit ok : f ( separator suffix prefix -- ) compiled pad place 2swap 2dup compiled pad +place compiled pad +place compiled pad +place c...
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#FreeBASIC
FreeBASIC
' FB 1.05.0 Win64   Dim As String s1, s2, sep Input "First string "; s1 Input "Second string "; s2 Input "Separator "; sep Print : Print s1 + sep + sep + s2 Sleep
http://rosettacode.org/wiki/ISBN13_check_digit
ISBN13 check digit
Task Validate the check digit of an ISBN-13 code:   Multiply every other digit by  3.   Add these numbers and the other digits.   Take the remainder of this number after division by  10.   If it is  0,   the ISBN-13 check digit is correct. Use the following codes for testing:   978-1734314502       (good)   ...
#Java
Java
public static void main(){ System.out.println(isISBN13("978-1734314502")); System.out.println(isISBN13("978-1734314509")); System.out.println(isISBN13("978-1788399081")); System.out.println(isISBN13("978-1788399083")); } public static boolean isISBN13(String in){ int pre = In...
http://rosettacode.org/wiki/Jaro_similarity
Jaro similarity
The Jaro distance is a measure of edit distance between two strings; its inverse, called the Jaro similarity, is a measure of two strings' similarity: the higher the value, the more similar the strings are. The score is normalized such that   0   equates to no similarities and   1   is an exact match. Definition The...
#PARI.2FGP
PARI/GP
  \\Jaro distance between 2 strings s1 and s2. \\ 4/12/16 aev jaroDist(s1,s2)={ my(vt1=Vecsmall(s1),vt2=Vecsmall(s2),n1=#s1,n2=#s2,d, md=max(n1,n2)\2-1,cs,ce,mc=0,tr=0,k=1,ds, s1m=vector(n1,z,0),s2m=vector(n2,z,0)); if(!n1||!n2, return(0)); for(i=1,n1, cs=max(1,i-md); ce=min(i+md+1,n2); for(j=cs,ce, if(...
http://rosettacode.org/wiki/Iterated_digits_squaring
Iterated digits squaring
If you add the square of the digits of a Natural number (an integer bigger than zero), you always end with either 1 or 89: 15 -> 26 -> 40 -> 16 -> 37 -> 58 -> 89 7 -> 49 -> 97 -> 130 -> 10 -> 1 An example in Python: >>> step = lambda x: sum(int(d) ** 2 for d in str(x)) >>> iterate = lambda x: x if x in [1, 89] else i...
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
sumDigitsSquared[n_Integer] := Total[IntegerDigits[n]^2] stopValues = Join[{1}, NestList[sumDigitsSquared, 89, 7]]; iterate[n_Integer] := NestWhile[sumDigitsSquared, n, Intersection[stopValues, {#}] == {} &]   numberOfDigits = 8; maxSum = numberOfDigits 9^2; loopVariables = ToExpression@Table["i" <> ToString[n], {...
http://rosettacode.org/wiki/Iterated_digits_squaring
Iterated digits squaring
If you add the square of the digits of a Natural number (an integer bigger than zero), you always end with either 1 or 89: 15 -> 26 -> 40 -> 16 -> 37 -> 58 -> 89 7 -> 49 -> 97 -> 130 -> 10 -> 1 An example in Python: >>> step = lambda x: sum(int(d) ** 2 for d in str(x)) >>> iterate = lambda x: x if x in [1, 89] else i...
#Nim
Nim
import tables   iterator digits(n: int): int = ## Yield the digits starting from the unit. var n = n while true: yield n mod 10 n = n div 10 if n == 0: break     func gen(n: int): int = ## Compute the chain. result = n while result notin [1, 89]: var s = 0 for d in digits(result): ...
http://rosettacode.org/wiki/Integer_sequence
Integer sequence
Task Create a program that, when run, would display all integers from   1   to   ∞   (or any relevant implementation limit),   in sequence   (i.e.   1, 2, 3, 4, etc)   if given enough time. An example may not be able to reach arbitrarily-large numbers based on implementations limits.   For example, if integer...
#ALGOL_W
ALGOL W
begin  % print the integers from 1 onwards  %  % Algol W only has 32-bit integers. When i reaches 2^32,  %  % an integer overflow event would be raised which by default,  %  % should terminate the program ...
http://rosettacode.org/wiki/Integer_sequence
Integer sequence
Task Create a program that, when run, would display all integers from   1   to   ∞   (or any relevant implementation limit),   in sequence   (i.e.   1, 2, 3, 4, etc)   if given enough time. An example may not be able to reach arbitrarily-large numbers based on implementations limits.   For example, if integer...
#Applesoft_BASIC
Applesoft BASIC
10 I% = 1 20 PRINT I%; 30 I% = I% + 1 40 PRINT ", "; 50 GOTO 20
http://rosettacode.org/wiki/Integer_overflow
Integer overflow
Some languages support one or more integer types of the underlying processor. This integer types have fixed size;   usually   8-bit,   16-bit,   32-bit,   or   64-bit. The integers supported by such a type can be   signed   or   unsigned. Arithmetic for machine level integers can often be done by single CPU instruct...
#Bracmat
Bracmat
#include <stdio.h>   int main (int argc, char *argv[]) { printf("Signed 32-bit:\n"); printf("%d\n", -(-2147483647-1)); printf("%d\n", 2000000000 + 2000000000); printf("%d\n", -2147483647 - 2147483647); printf("%d\n", 46341 * 46341); printf("%d\n", (-2147483647-1) / -1); printf("Signed 64-bit:\n"); print...
http://rosettacode.org/wiki/Input_loop
Input loop
Input loop is part of Short Circuit's Console Program Basics selection. Task Read from a text stream either word-by-word or line-by-line until the stream runs out of data. The stream will have an unknown amount of data on it.
#AArch64_Assembly
AArch64 Assembly
  /* ARM assembly AARCH64 Raspberry PI 3B */ /* program inputLoop64.s */   /*******************************************/ /* Constantes file */ /*******************************************/ /* for this file see task include a file in language AArch64 assembly*/ .include "../includeConstantesAR...
http://rosettacode.org/wiki/Isqrt_(integer_square_root)_of_X
Isqrt (integer square root) of X
Sometimes a function is needed to find the integer square root of   X,   where   X   can be a real non─negative number. Often   X   is actually a non─negative integer. For the purposes of this task,   X   can be an integer or a real number,   but if it simplifies things in your computer programming language,   assume...
#J
J
  isqrt_float=: <.@:%: isqrt_newton=: 9&$: :(x:@:<.@:-:@:(] + x:@:<.@:%)^:_&>~&:x:)     align=: (|.~ i.&' ')"1 comma=: (' ' -.~ [: }: [: , [: (|.) _3 (',' ,~ |.)\ |.)@":&> While=: {{ u^:(0-.@:-:v)^:_ }}   isqrt=: 3 :0&> y =. x: y NB. q is a power of 4 that's greater than y. Append 0 0 under binary representation q ...
http://rosettacode.org/wiki/Inverted_index
Inverted index
An Inverted Index is a data structure used to create full text search. Task Given a set of text files, implement a program to create an inverted index. Also create a user interface to do a search using that inverted index which returns a list of files that contain the query term / terms. The search index can be i...
#Clojure
Clojure
(ns inverted-index.core (:require [clojure.set :as sets] [clojure.java.io :as io]))   (def pattern #"\w+") ; Java regex for a raw term: here a substring of alphanums (defn normalize [match] (.toLowerCase match)) ; normalization of a raw term   (defn term-seq [text] (map normalize (re-seq pattern text...
http://rosettacode.org/wiki/Introspection
Introspection
Task verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old. check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop). Extra credit Repor...
#E
E
def version := interp.getProps()["e.version"]
http://rosettacode.org/wiki/Introspection
Introspection
Task verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old. check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop). Extra credit Repor...
#EchoLisp
EchoLisp
  (version) → EchoLisp - 2.50.3 📗 local-db: db.version: 3   (when (< (version) 2.6) (writeln "Please reload EchoLisp : CTRL-F5, CMD-R or other...") (exit))   (if (and (bound? 'bloop) (bound? 'abs) (procedure? abs)) (abs bloop) 'NOT-HERE) → NOT-HERE   (define bloop -777) → bloop (if (and (bound? 'bloo...
http://rosettacode.org/wiki/Josephus_problem
Josephus problem
Josephus problem is a math puzzle with a grim description: n {\displaystyle n} prisoners are standing on a circle, sequentially numbered from 0 {\displaystyle 0} to n − 1 {\displaystyle n-1} . An executioner walks along the circle, starting from prisoner 0 {\displaystyle 0} , removing eve...
#Frink
Frink
  killingCycle[prisonerCount,killStep = 2] := { i = 0 killed = new array prisoners = array[0 to prisonerCount - 1] while length[prisoners] > 1 { i = (i + killStep - 1) mod length[prisoners] killed.push[prisoners.remove[i]] // Remove the killed prisoner from the prisoners array and add it to t...
http://rosettacode.org/wiki/Intersecting_number_wheels
Intersecting number wheels
A number wheel has: A name which is an uppercase letter. A set of ordered values which are either numbers or names. A number is generated/yielded from a named wheel by: 1. Starting at the first value of the named wheel and advancing through subsequent values and wrapping around to the first value to form a "wheel"...
#JavaScript
JavaScript
(() => { 'use strict';   // main :: IO () const main = () => {   // clockWorkTick :: Dict -> (Dict, Char) const clockWorkTick = wheelMap => { // The new configuration of the wheels, tupled with // a digit found by recursive descent from a single // click o...
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#Frink
Frink
$ java -cp frink.jar frink.parser.Frink   f[a,b,s] := "$a$s$s$b" f["Rosetta", "Code", ":"]
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#F.C5.8Drmul.C3.A6
Fōrmulæ
~% gap   ######### ###### ########### ### ############# ###### ############ #### ############## ######## ############# ##### ############### ######## ##### ###### ##### #####...
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#GAP
GAP
~% gap   ######### ###### ########### ### ############# ###### ############ #### ############## ######## ############# ##### ############### ######## ##### ###### ##### #####...
http://rosettacode.org/wiki/ISBN13_check_digit
ISBN13 check digit
Task Validate the check digit of an ISBN-13 code:   Multiply every other digit by  3.   Add these numbers and the other digits.   Take the remainder of this number after division by  10.   If it is  0,   the ISBN-13 check digit is correct. Use the following codes for testing:   978-1734314502       (good)   ...
#jq
jq
  def isbn_check: def digits: tostring | explode | map( select(. >= 48 and . <= 57) | [.] | implode | tonumber); def sum(s): reduce s as $x (null; . + $x); digits | . as $digits | sum(range(0;length;2) | $digits[.]) as $one | (3 * sum(range(1;length;2) | $digits[.])) as $two | (($one+$two) % 10) == 0...
http://rosettacode.org/wiki/ISBN13_check_digit
ISBN13 check digit
Task Validate the check digit of an ISBN-13 code:   Multiply every other digit by  3.   Add these numbers and the other digits.   Take the remainder of this number after division by  10.   If it is  0,   the ISBN-13 check digit is correct. Use the following codes for testing:   978-1734314502       (good)   ...
#Julia
Julia
function isbncheck(str) return sum(iseven(i) ? 3 * parse(Int, ch) : parse(Int, ch) for (i, ch) in enumerate(replace(str, r"\D" => ""))) % 10 == 0 end   const testingcodes = ["978-1734314502", "978-1734314509", "978-1788399081", "978-1788399083"]   for code in testingcodes println(...
http://rosettacode.org/wiki/Jaro_similarity
Jaro similarity
The Jaro distance is a measure of edit distance between two strings; its inverse, called the Jaro similarity, is a measure of two strings' similarity: the higher the value, the more similar the strings are. The score is normalized such that   0   equates to no similarities and   1   is an exact match. Definition The...
#Pascal
Pascal
  program Jaro_distance;   uses SysUtils, Math;   //converted from C source by /u/bleuge function ssJaroWinkler(s1, s2: string): double; var l1, l2, match_distance, matches, i, k, trans: integer; bs1, bs2: array[1..255] of boolean; //used to avoid getmem, max string length is 255 begin l1 := length(s1); l2 := l...
http://rosettacode.org/wiki/Iterated_digits_squaring
Iterated digits squaring
If you add the square of the digits of a Natural number (an integer bigger than zero), you always end with either 1 or 89: 15 -> 26 -> 40 -> 16 -> 37 -> 58 -> 89 7 -> 49 -> 97 -> 130 -> 10 -> 1 An example in Python: >>> step = lambda x: sum(int(d) ** 2 for d in str(x)) >>> iterate = lambda x: x if x in [1, 89] else i...
#Oberon-2
Oberon-2
  MODULE DigitsSquaring; IMPORT Out;   VAR i,hits89: LONGINT;   PROCEDURE Squaring(n: LONGINT): LONGINT; VAR d, sum: LONGINT; BEGIN LOOP sum := 0; WHILE n > 0 DO d := n MOD 10; INC(sum,d * d); n := n DIV 10 END; IF (sum = 1) OR (sum = 89) THEN EXIT END; ...
http://rosettacode.org/wiki/Integer_sequence
Integer sequence
Task Create a program that, when run, would display all integers from   1   to   ∞   (or any relevant implementation limit),   in sequence   (i.e.   1, 2, 3, 4, etc)   if given enough time. An example may not be able to reach arbitrarily-large numbers based on implementations limits.   For example, if integer...
#ARM_Assembly
ARM Assembly
.text .global main   @ An ARM program that keeps incrementing R0 forever @ @ If desired, a call to some 'PRINT' routine -- @ which would depend on the OS -- could be included   main: mov r0, #0 @ start with R0 = 0   repeat: @ call to 'PRINT' routine add r0, r0, #1 @ increme...
http://rosettacode.org/wiki/Integer_sequence
Integer sequence
Task Create a program that, when run, would display all integers from   1   to   ∞   (or any relevant implementation limit),   in sequence   (i.e.   1, 2, 3, 4, etc)   if given enough time. An example may not be able to reach arbitrarily-large numbers based on implementations limits.   For example, if integer...
#ArnoldC
ArnoldC
IT'S SHOWTIME HEY CHRISTMAS TREE n YOU SET US UP @NO PROBLEMO STICK AROUND @NO PROBLEMO TALK TO THE HAND n GET TO THE CHOPPER n HERE IS MY INVITATION n GET UP @NO PROBLEMO ENOUGH TALK CHILL YOU HAVE BEEN TERMINATED
http://rosettacode.org/wiki/Integer_overflow
Integer overflow
Some languages support one or more integer types of the underlying processor. This integer types have fixed size;   usually   8-bit,   16-bit,   32-bit,   or   64-bit. The integers supported by such a type can be   signed   or   unsigned. Arithmetic for machine level integers can often be done by single CPU instruct...
#C
C
#include <stdio.h>   int main (int argc, char *argv[]) { printf("Signed 32-bit:\n"); printf("%d\n", -(-2147483647-1)); printf("%d\n", 2000000000 + 2000000000); printf("%d\n", -2147483647 - 2147483647); printf("%d\n", 46341 * 46341); printf("%d\n", (-2147483647-1) / -1); printf("Signed 64-bit:\n"); print...
http://rosettacode.org/wiki/Input_loop
Input loop
Input loop is part of Short Circuit's Console Program Basics selection. Task Read from a text stream either word-by-word or line-by-line until the stream runs out of data. The stream will have an unknown amount of data on it.
#Action.21
Action!
PROC ReadStream(BYTE stream) CHAR ARRAY line(255)   WHILE Eof(stream)=0 DO InputSD(stream,line) PrintE(line) OD RETURN   PROC Main() BYTE streamId=[1]   Close(streamId) Open(streamId,"H6:INPUT_PU.ACT",4) PrintE("Reading from stream...") PutE() ReadStream(streamId) Close(streamId) RETURN
http://rosettacode.org/wiki/Isqrt_(integer_square_root)_of_X
Isqrt (integer square root) of X
Sometimes a function is needed to find the integer square root of   X,   where   X   can be a real non─negative number. Often   X   is actually a non─negative integer. For the purposes of this task,   X   can be an integer or a real number,   but if it simplifies things in your computer programming language,   assume...
#Java
Java
import java.math.BigInteger;   public class Isqrt { private static BigInteger isqrt(BigInteger x) { if (x.compareTo(BigInteger.ZERO) < 0) { throw new IllegalArgumentException("Argument cannot be negative"); } var q = BigInteger.ONE; while (q.compareTo(x) <= 0) { ...
http://rosettacode.org/wiki/Inverted_index
Inverted index
An Inverted Index is a data structure used to create full text search. Task Given a set of text files, implement a program to create an inverted index. Also create a user interface to do a search using that inverted index which returns a list of files that contain the query term / terms. The search index can be i...
#CoffeeScript
CoffeeScript
  fs = require 'fs'   make_index = (fns) -> # words are indexed by filename and 1-based line numbers index = {} for fn in fns for line, line_num in fs.readFileSync(fn).toString().split '\n' words = get_words line for word in words word = mangle(word) index[word] ||= [] inde...
http://rosettacode.org/wiki/Introspection
Introspection
Task verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old. check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop). Extra credit Repor...
#Erlang
Erlang
  -module( introspection ).   -export( [task/0] ).   task() -> exit_if_too_old( erlang:system_info(otp_release) ), Bloop = lists:keyfind( bloop, 1, ?MODULE:module_info(functions) ), Abs = lists:keyfind( abs, 1, erlang:module_info(exports) ), io:fwrite( "abs( bloop ) => ~p~n", [call_abs_with_bloop(Abs, B...
http://rosettacode.org/wiki/Josephus_problem
Josephus problem
Josephus problem is a math puzzle with a grim description: n {\displaystyle n} prisoners are standing on a circle, sequentially numbered from 0 {\displaystyle 0} to n − 1 {\displaystyle n-1} . An executioner walks along the circle, starting from prisoner 0 {\displaystyle 0} , removing eve...
#F.C5.8Drmul.C3.A6
Fōrmulæ
package main   import "fmt"   // basic task function func finalSurvivor(n, k int) int { // argument validation omitted circle := make([]int, n) for i := range circle { circle[i] = i } k-- exPos := 0 for len(circle) > 1 { exPos = (exPos + k) % len(circle) circle = appe...
http://rosettacode.org/wiki/Intersecting_number_wheels
Intersecting number wheels
A number wheel has: A name which is an uppercase letter. A set of ordered values which are either numbers or names. A number is generated/yielded from a named wheel by: 1. Starting at the first value of the named wheel and advancing through subsequent values and wrapping around to the first value to form a "wheel"...
#Julia
Julia
const d1 = Dict("A" => [["1", "2", "3"], 1]) const d2 = Dict("A" => [["1", "B", "2"], 1], "B" => [["3", "4"], 1]) const d3 = Dict("A" => [["1", "D", "D"], 1], "D" => [["6", "7", "8"], 1]) const d4 = Dict("A" => [["1", "B", "C"], 1], "B" => [["3", "4"], 1], "C" => [["5", "B"], 1])   function getvalue!(wheelname, all...
http://rosettacode.org/wiki/Intersecting_number_wheels
Intersecting number wheels
A number wheel has: A name which is an uppercase letter. A set of ordered values which are either numbers or names. A number is generated/yielded from a named wheel by: 1. Starting at the first value of the named wheel and advancing through subsequent values and wrapping around to the first value to form a "wheel"...
#Kotlin
Kotlin
import java.util.Collections import java.util.stream.IntStream   object WheelController { private val IS_NUMBER = "[0-9]".toRegex() private const val TWENTY = 20 private var wheelMap = mutableMapOf<String, WheelModel>()   private fun advance(wheel: String) { val w = wheelMap[wheel] if (w...
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#Go
Go
package main   import "fmt"   func f(s1, s2, sep string) string { return s1 + sep + sep + s2 }   func main() { fmt.Println(f("Rosetta", "Code", ":")) }
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#Groovy
Groovy
C:\Apps\groovy>groovysh Groovy Shell (1.6.2, JVM: 1.6.0_13) Type 'help' or '\h' for help. --------------------------------------------------------------------------------------------------- groovy:000> f = { a, b, sep -> a + sep + sep + b } ===> groovysh_evaluate$_run_closure1@5e8d7d groovy:000> println f('Rosetta','Co...
http://rosettacode.org/wiki/ISBN13_check_digit
ISBN13 check digit
Task Validate the check digit of an ISBN-13 code:   Multiply every other digit by  3.   Add these numbers and the other digits.   Take the remainder of this number after division by  10.   If it is  0,   the ISBN-13 check digit is correct. Use the following codes for testing:   978-1734314502       (good)   ...
#Kotlin
Kotlin
  fun isValidISBN13(text: String): Boolean { val isbn = text.replace(Regex("[- ]"), "") return isbn.length == 13 && isbn.map { it - '0' } .mapIndexed { index, value -> when (index % 2) { 0 -> value else -> 3 * value } } .sum() % 10 == 0 }  
http://rosettacode.org/wiki/ISBN13_check_digit
ISBN13 check digit
Task Validate the check digit of an ISBN-13 code:   Multiply every other digit by  3.   Add these numbers and the other digits.   Take the remainder of this number after division by  10.   If it is  0,   the ISBN-13 check digit is correct. Use the following codes for testing:   978-1734314502       (good)   ...
#langur
langur
val .isbn13checkdigit = f(var .s) { .s = replace(.s, RE/[\- ]/) matching(re/^[0-9]{13}$/, .s) and fold(f{+}, map [_, f{x 3}], s2n .s) div 10 }   val .tests = h{ "978-1734314502": true, "978-1734314509": false, "978-1788399081": true, "978-1788399083": false, }   for .key of .tests { ...
http://rosettacode.org/wiki/Jaro_similarity
Jaro similarity
The Jaro distance is a measure of edit distance between two strings; its inverse, called the Jaro similarity, is a measure of two strings' similarity: the higher the value, the more similar the strings are. The score is normalized such that   0   equates to no similarities and   1   is an exact match. Definition The...
#Perl
Perl
use strict; use warnings; use List::Util qw(min max);   sub jaro { my($s, $t) = @_; my(@s_matches, @t_matches, $matches);   return 1 if $s eq $t;   my($s_len, @s) = (length $s, split //, $s); my($t_len, @t) = (length $t, split //, $t);   my $match_distance = int (max($s_len, $t_len) / 2) - 1; ...
http://rosettacode.org/wiki/Iterated_digits_squaring
Iterated digits squaring
If you add the square of the digits of a Natural number (an integer bigger than zero), you always end with either 1 or 89: 15 -> 26 -> 40 -> 16 -> 37 -> 58 -> 89 7 -> 49 -> 97 -> 130 -> 10 -> 1 An example in Python: >>> step = lambda x: sum(int(d) ** 2 for d in str(x)) >>> iterate = lambda x: x if x in [1, 89] else i...
#Objeck
Objeck
class Abbreviations { function : Main(args : String[]) ~ Nil { Count89s(1000000)->PrintLine(); Count89s(100000000)->PrintLine(); }   function : Count89s(limit : Int) ~ Int { if(limit < 1) { return 0; };   result := 0; ends := Int->New[Int->Min(limit, 9 * 9 * 9 + 2)]; for(i := 1; ...
http://rosettacode.org/wiki/Integer_sequence
Integer sequence
Task Create a program that, when run, would display all integers from   1   to   ∞   (or any relevant implementation limit),   in sequence   (i.e.   1, 2, 3, 4, etc)   if given enough time. An example may not be able to reach arbitrarily-large numbers based on implementations limits.   For example, if integer...
#Arturo
Arturo
i:0 while ø [ print i inc 'i ]
http://rosettacode.org/wiki/Integer_sequence
Integer sequence
Task Create a program that, when run, would display all integers from   1   to   ∞   (or any relevant implementation limit),   in sequence   (i.e.   1, 2, 3, 4, etc)   if given enough time. An example may not be able to reach arbitrarily-large numbers based on implementations limits.   For example, if integer...
#AutoHotkey
AutoHotkey
x=0 Loop TrayTip, Count, % ++x
http://rosettacode.org/wiki/Inheritance/Multiple
Inheritance/Multiple
Multiple inheritance allows to specify that one class is a subclass of several other classes. Some languages allow multiple inheritance for arbitrary classes,   others restrict it to interfaces,   some don't allow it at all. Task Write two classes (or interfaces) Camera and MobilePhone,   then write a class Camer...
#Ada
Ada
package Multiple_Interfaces is type Camera is tagged null record; type Mobile_Phone is limited Interface; type Camera_Phone is new Camera and Mobile_Phone with null record; end Multiple_Interfaces;
http://rosettacode.org/wiki/Integer_overflow
Integer overflow
Some languages support one or more integer types of the underlying processor. This integer types have fixed size;   usually   8-bit,   16-bit,   32-bit,   or   64-bit. The integers supported by such a type can be   signed   or   unsigned. Arithmetic for machine level integers can often be done by single CPU instruct...
#C.23
C#
using System;   public class IntegerOverflow { public static void Main() { unchecked { Console.WriteLine("For 32-bit signed integers:"); Console.WriteLine(-(-2147483647 - 1)); Console.WriteLine(2000000000 + 2000000000); Console.WriteLine(-2147483647 - 21474836...
http://rosettacode.org/wiki/Input_loop
Input loop
Input loop is part of Short Circuit's Console Program Basics selection. Task Read from a text stream either word-by-word or line-by-line until the stream runs out of data. The stream will have an unknown amount of data on it.
#Ada
Ada
with Ada.Text_Io; use Ada.Text_Io;   procedure Read_Stream is Line : String(1..10); Length : Natural; begin while not End_Of_File loop Get_Line(Line, Length); -- read up to 10 characters at a time Put(Line(1..Length)); -- The current line of input data may be longer than the string receiving ...
http://rosettacode.org/wiki/Input_loop
Input loop
Input loop is part of Short Circuit's Console Program Basics selection. Task Read from a text stream either word-by-word or line-by-line until the stream runs out of data. The stream will have an unknown amount of data on it.
#Aime
Aime
void read_stream(file f) { text s;   while (f_line(f, s) != -1) { # the read line available as -s- } }
http://rosettacode.org/wiki/Isqrt_(integer_square_root)_of_X
Isqrt (integer square root) of X
Sometimes a function is needed to find the integer square root of   X,   where   X   can be a real non─negative number. Often   X   is actually a non─negative integer. For the purposes of this task,   X   can be an integer or a real number,   but if it simplifies things in your computer programming language,   assume...
#jq
jq
# For gojq def idivide($j): . as $i | ($i % $j) as $mod | ($i - $mod) / $j ;   # input should be non-negative def isqrt: . as $x | 1 | until(. > $x; . * 4) as $q | {$q, $x, r: 0} | until( .q <= 1; .q |= idivide(4) | .t = .x - .r - .q | .r |= idivide(2) | if .t >...
http://rosettacode.org/wiki/Isqrt_(integer_square_root)_of_X
Isqrt (integer square root) of X
Sometimes a function is needed to find the integer square root of   X,   where   X   can be a real non─negative number. Often   X   is actually a non─negative integer. For the purposes of this task,   X   can be an integer or a real number,   but if it simplifies things in your computer programming language,   assume...
#Julia
Julia
using Formatting   function integer_sqrt(x) @assert(x >= 0) q = one(x) while q <= x q <<= 2 end z, r = x, zero(x) while q > 1 q >>= 2 t = z - r - q r >>= 1 if t >= 0 z = t r += q end end return r end   println("The i...
http://rosettacode.org/wiki/Inverted_index
Inverted index
An Inverted Index is a data structure used to create full text search. Task Given a set of text files, implement a program to create an inverted index. Also create a user interface to do a search using that inverted index which returns a list of files that contain the query term / terms. The search index can be i...
#Common_Lisp
Common Lisp
(defpackage rosettacode.inverted-index (:use cl)) (in-package rosettacode.inverted-index)   ;; Return a list of tokens in the string LINE. This is rather ;; complicated as CL has no good standard function to do it. (defun tokenize (line) (let ((start 0) (len (length line))) (loop for s = (position-if #'alphanu...
http://rosettacode.org/wiki/Introspection
Introspection
Task verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old. check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop). Extra credit Repor...
#Factor
Factor
: if-older ( n true false -- ) [ build > ] 2dip if ; inline   : when-older ( n true -- ) [ ] if-older ; inline : unless-older ( n false -- ) [ [ ] ] dip if-older ; inline   900 [ "Your version of Factor is too old." print 1 exit ] when-older
http://rosettacode.org/wiki/Introspection
Introspection
Task verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old. check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop). Extra credit Repor...
#Forth
Forth
s" MAX-U" environment? [IF] 0xffffffff <> [IF] .( Requires 32 bits! ) bye [THEN] [THEN]   [defined] bloop [if] [defined] abs [if] bloop @ abs [then] [then]
http://rosettacode.org/wiki/Josephus_problem
Josephus problem
Josephus problem is a math puzzle with a grim description: n {\displaystyle n} prisoners are standing on a circle, sequentially numbered from 0 {\displaystyle 0} to n − 1 {\displaystyle n-1} . An executioner walks along the circle, starting from prisoner 0 {\displaystyle 0} , removing eve...
#Go
Go
package main   import "fmt"   // basic task function func finalSurvivor(n, k int) int { // argument validation omitted circle := make([]int, n) for i := range circle { circle[i] = i } k-- exPos := 0 for len(circle) > 1 { exPos = (exPos + k) % len(circle) circle = appe...
http://rosettacode.org/wiki/Intersecting_number_wheels
Intersecting number wheels
A number wheel has: A name which is an uppercase letter. A set of ordered values which are either numbers or names. A number is generated/yielded from a named wheel by: 1. Starting at the first value of the named wheel and advancing through subsequent values and wrapping around to the first value to form a "wheel"...
#Maple
Maple
  with(ArrayTools):   module Wheel() option object; local spokes := Array([1,2,3]); local currentSpoke := 1;   export currentValue::static := proc(self::Wheel) local valueOut; if type(self:-spokes[self:-currentSpoke], integer) then valueOut := self:-spokes[self:-currentSpoke]: else valueOut := currentVa...
http://rosettacode.org/wiki/Intersecting_number_wheels
Intersecting number wheels
A number wheel has: A name which is an uppercase letter. A set of ordered values which are either numbers or names. A number is generated/yielded from a named wheel by: 1. Starting at the first value of the named wheel and advancing through subsequent values and wrapping around to the first value to form a "wheel"...
#Nim
Nim
import strutils, tables   type   ElemKind = enum eValue, eWheel   Elem = object case kind: ElemKind of eValue: value: Natural of eWheel: name: char   Wheel = ref object elems: seq[Elem] index: Natural   Wheels = Table[char, Wheel]   WheelDescription = tuple[name: char; elems: s...
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#Haskell
Haskell
$ ghci ___ ___ _ / _ \ /\ /\/ __(_) / /_\// /_/ / / | | GHC Interactive, version 6.4.2, for Haskell 98. / /_\\/ __ / /___| | http://www.haskell.org/ghc/ \____/\/ /_/\____/|_| Type :? for help.   Loading package base-1.0 ... linking ... done. Prelude> let f as bs sep = as ++ sep ++ sep ++...
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#HicEst
HicEst
CHARACTER A*40, B*40, C*40   READ(Text=$CMD_LINE, Format="'','','',") A, B, C WRITE(ClipBoard, Name) A, B, C ! A=Rosetta; B=Code; C=:;   WRITE(ClipBoard) TRIM(A) // ':' // TRIM(C) // TRIM(B) ! Rosetta::Code
http://rosettacode.org/wiki/ISBN13_check_digit
ISBN13 check digit
Task Validate the check digit of an ISBN-13 code:   Multiply every other digit by  3.   Add these numbers and the other digits.   Take the remainder of this number after division by  10.   If it is  0,   the ISBN-13 check digit is correct. Use the following codes for testing:   978-1734314502       (good)   ...
#Lua
Lua
function checkIsbn13(isbn) local count = 0 local sum = 0 for c in isbn:gmatch"." do if c == ' ' or c == '-' then -- skip elseif c < '0' or '9' < c then return false else local digit = c - '0' if (count % 2) > 0 then sum ...
http://rosettacode.org/wiki/Jaro_similarity
Jaro similarity
The Jaro distance is a measure of edit distance between two strings; its inverse, called the Jaro similarity, is a measure of two strings' similarity: the higher the value, the more similar the strings are. The score is normalized such that   0   equates to no similarities and   1   is an exact match. Definition The...
#Phix
Phix
function jaro(string str1, str2) str1 = trim(upper(str1)) str2 = trim(upper(str2)) integer len1 = length(str1), len2 = length(str2), match_distance = floor(max(len1,len2)/2)-1, match_count = 0, half_transposed = 0 if len1==0 then return len2==0 end if ...
http://rosettacode.org/wiki/Iterated_digits_squaring
Iterated digits squaring
If you add the square of the digits of a Natural number (an integer bigger than zero), you always end with either 1 or 89: 15 -> 26 -> 40 -> 16 -> 37 -> 58 -> 89 7 -> 49 -> 97 -> 130 -> 10 -> 1 An example in Python: >>> step = lambda x: sum(int(d) ** 2 for d in str(x)) >>> iterate = lambda x: x if x in [1, 89] else i...
#Oforth
Oforth
: sq_digits(n) while (n 1 <> n 89 <> and ) [ 0 while(n) [ n 10 /mod ->n dup * + ] ->n ] n ;   : iterDigits | i | 0 100000000 loop: i [ i sq_digits 89 &= + ] . ;
http://rosettacode.org/wiki/Iterated_digits_squaring
Iterated digits squaring
If you add the square of the digits of a Natural number (an integer bigger than zero), you always end with either 1 or 89: 15 -> 26 -> 40 -> 16 -> 37 -> 58 -> 89 7 -> 49 -> 97 -> 130 -> 10 -> 1 An example in Python: >>> step = lambda x: sum(int(d) ** 2 for d in str(x)) >>> iterate = lambda x: x if x in [1, 89] else i...
#PARI.2FGP
PARI/GP
ssd(n)=n=digits(n); sum(i=1, #n, n[i]^2); happy(n)=while(n>6, n=ssd(n)); n==1; ct(n)=my(f=n!,s=10^n-1,d); forvec(v=vector(9,i,[0,n]), d=vector(9,i, if(i>8,n,v[i+1])-v[i]); if(happy(sum(i=1,9,d[i]*i^2)), s-=f/prod(i=1,9,d[i]!)/v[1]!), 1); s; ct(8)
http://rosettacode.org/wiki/Integer_sequence
Integer sequence
Task Create a program that, when run, would display all integers from   1   to   ∞   (or any relevant implementation limit),   in sequence   (i.e.   1, 2, 3, 4, etc)   if given enough time. An example may not be able to reach arbitrarily-large numbers based on implementations limits.   For example, if integer...
#AWK
AWK
BEGIN { for( i=0; i != i + 1; i++ ) print( i ) }
http://rosettacode.org/wiki/Integer_sequence
Integer sequence
Task Create a program that, when run, would display all integers from   1   to   ∞   (or any relevant implementation limit),   in sequence   (i.e.   1, 2, 3, 4, etc)   if given enough time. An example may not be able to reach arbitrarily-large numbers based on implementations limits.   For example, if integer...
#Axe
Axe
While getKey(0) End 0→I Repeat getKey(0) Disp I▶Dec,i I++ EndIf I=0
http://rosettacode.org/wiki/Inheritance/Multiple
Inheritance/Multiple
Multiple inheritance allows to specify that one class is a subclass of several other classes. Some languages allow multiple inheritance for arbitrary classes,   others restrict it to interfaces,   some don't allow it at all. Task Write two classes (or interfaces) Camera and MobilePhone,   then write a class Camer...
#Aikido
Aikido
interface Camera { }   interface Mobile_Phone { }   class Camera_Phone implements Camera, Mobile_Phone { }
http://rosettacode.org/wiki/Inheritance/Multiple
Inheritance/Multiple
Multiple inheritance allows to specify that one class is a subclass of several other classes. Some languages allow multiple inheritance for arbitrary classes,   others restrict it to interfaces,   some don't allow it at all. Task Write two classes (or interfaces) Camera and MobilePhone,   then write a class Camer...
#BBC_BASIC
BBC BASIC
INSTALL @lib$+"CLASSLIB"   DIM Camera{TakePicture} PROC_class(Camera{})   DIM MobilePhone{MakeCall} PROC_class(MobilePhone{})   DIM CameraPhone{methods} PROC_inherit(CameraPhone{}, Camera{}) PROC_inherit(CameraPhone{}, MobilePhone{}) PROC_class(CameraPhone{})
http://rosettacode.org/wiki/Inheritance/Multiple
Inheritance/Multiple
Multiple inheritance allows to specify that one class is a subclass of several other classes. Some languages allow multiple inheritance for arbitrary classes,   others restrict it to interfaces,   some don't allow it at all. Task Write two classes (or interfaces) Camera and MobilePhone,   then write a class Camer...
#C
C
  typedef struct{ double focalLength; double resolution; double memory; }Camera;   typedef struct{ double balance; double batteryLevel; char** contacts; }Phone;   typedef struct{ Camera cameraSample; Phone phoneSample; }CameraPhone;  
http://rosettacode.org/wiki/Inheritance/Multiple
Inheritance/Multiple
Multiple inheritance allows to specify that one class is a subclass of several other classes. Some languages allow multiple inheritance for arbitrary classes,   others restrict it to interfaces,   some don't allow it at all. Task Write two classes (or interfaces) Camera and MobilePhone,   then write a class Camer...
#C.23
C#
interface ICamera { // ... }   class MobilePhone { // ... }   class CameraPhone: ICamera, MobilePhone { // ... }
http://rosettacode.org/wiki/Integer_overflow
Integer overflow
Some languages support one or more integer types of the underlying processor. This integer types have fixed size;   usually   8-bit,   16-bit,   32-bit,   or   64-bit. The integers supported by such a type can be   signed   or   unsigned. Arithmetic for machine level integers can often be done by single CPU instruct...
#C.2B.2B
C++
#include <iostream> #include <cstdint> #include <limits>   int main (int argc, char *argv[]) { std::cout << std::boolalpha << std::numeric_limits<std::int32_t>::is_modulo << '\n' << std::numeric_limits<std::uint32_t>::is_modulo << '\n' // always true << std::numeric_limits<std::int64_t>::is_modulo << '\n' << ...
http://rosettacode.org/wiki/Input_loop
Input loop
Input loop is part of Short Circuit's Console Program Basics selection. Task Read from a text stream either word-by-word or line-by-line until the stream runs out of data. The stream will have an unknown amount of data on it.
#ALGOL_68
ALGOL 68
main:( PROC raise logical file end = (REF FILE f) BOOL: ( except logical file end ); on logical file end(stand in, raise logical file end); DO print(read string); read(new line); print(new line) OD; except logical file end: SKIP )
http://rosettacode.org/wiki/Input_loop
Input loop
Input loop is part of Short Circuit's Console Program Basics selection. Task Read from a text stream either word-by-word or line-by-line until the stream runs out of data. The stream will have an unknown amount of data on it.
#ALGOL_W
ALGOL W
begin string(80) line;  % allow the program to continue after reaching end-of-file %  % without this, end-of-file would cause a run-time error  % ENDFILE := EXCEPTION( false, 1, 0, false, "EOF" );  % read lines until end of file  % read( line ); while not XCPNOTED(EN...
http://rosettacode.org/wiki/Isqrt_(integer_square_root)_of_X
Isqrt (integer square root) of X
Sometimes a function is needed to find the integer square root of   X,   where   X   can be a real non─negative number. Often   X   is actually a non─negative integer. For the purposes of this task,   X   can be an integer or a real number,   but if it simplifies things in your computer programming language,   assume...
#Kotlin
Kotlin
import java.math.BigInteger   fun isqrt(x: BigInteger): BigInteger { if (x < BigInteger.ZERO) { throw IllegalArgumentException("Argument cannot be negative") } var q = BigInteger.ONE while (q <= x) { q = q.shiftLeft(2) } var z = x var r = BigInteger.ZERO while (q > BigInt...
http://rosettacode.org/wiki/Inverted_index
Inverted index
An Inverted Index is a data structure used to create full text search. Task Given a set of text files, implement a program to create an inverted index. Also create a user interface to do a search using that inverted index which returns a list of files that contain the query term / terms. The search index can be i...
#D
D
import std.stdio, std.algorithm, std.string, std.file, std.regex;   void main() { string[][string] index;   void parseFile(in string fn) { if (!exists(fn) || !isFile(fn)) throw new Exception("File not found");   foreach (word; readText(fn).splitter(regex(r"\W"))) { word =...
http://rosettacode.org/wiki/Introspection
Introspection
Task verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old. check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop). Extra credit Repor...
#FreeBASIC
FreeBASIC
' FB 1.05.0 Win64   #If __FB_VERSION__ < "1.06.0" #Error "Compiler version is too old - needs to be 1.06.0 or later" #EndIf   Dim bloop As Integer = -15 #IfDef bloop #IfDef Abs Print "Abs(bloop) = "; Abs(bloop) #Else Print "Abs is not available" #EndIf #Else Print "bloop does not exist" #EndIf Sleep
http://rosettacode.org/wiki/Introspection
Introspection
Task verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old. check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop). Extra credit Repor...
#GAP
GAP
# Apply a function to a value, given variable names for both function and value CheckEval := function(fun, val) local f, x; if IsBoundGlobal(fun) and IsBoundGlobal(val) then f := ValueGlobal(fun); x := ValueGlobal(val); return f(x); fi; end;   bloop := -1; CheckEval("AbsInt", "bloop"); # 1     # Sum of integer...
http://rosettacode.org/wiki/Josephus_problem
Josephus problem
Josephus problem is a math puzzle with a grim description: n {\displaystyle n} prisoners are standing on a circle, sequentially numbered from 0 {\displaystyle 0} to n − 1 {\displaystyle n-1} . An executioner walks along the circle, starting from prisoner 0 {\displaystyle 0} , removing eve...
#Groovy
Groovy
int[] Josephus (int size, int kill, int survivors) { // init user pool def users = new int[size];   // give initial values such that [0] = 1 (first person) [1] = 2 (second person) etc users.eachWithIndex() {obj, i -> users[i] = i + 1};   // keep track of which person we are on (ranging from 1 to kil...
http://rosettacode.org/wiki/Intersecting_number_wheels
Intersecting number wheels
A number wheel has: A name which is an uppercase letter. A set of ordered values which are either numbers or names. A number is generated/yielded from a named wheel by: 1. Starting at the first value of the named wheel and advancing through subsequent values and wrapping around to the first value to form a "wheel"...
#Perl
Perl
use strict; use warnings; use feature 'say';   sub get_next { my($w,%wheels) = @_; my $wh = \@{$wheels{$w}}; # reference, not a copy my $value = $$wh[0][$$wh[1]]; $$wh[1] = ($$wh[1]+1) % @{$$wh[0]}; defined $wheels{$value} ? get_next($value,%wheels) : $value; }   sub spin_wheels { my(%wheels) = ...
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#Huginn
Huginn
$ io Io 20110905 Io> f := method(str1,str2,sep, ... str1 .. sep .. sep .. str2) ==> method(str1, str2, sep, str1 .. sep .. sep .. str2 ) Io> f("Rosetta","Code",":") ==> Rosetta::Code Io> writeln("I am going to exit now") I am going to exit now ==> nil Io> exit $
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#Io
Io
$ io Io 20110905 Io> f := method(str1,str2,sep, ... str1 .. sep .. sep .. str2) ==> method(str1, str2, sep, str1 .. sep .. sep .. str2 ) Io> f("Rosetta","Code",":") ==> Rosetta::Code Io> writeln("I am going to exit now") I am going to exit now ==> nil Io> exit $
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#J
J
f=: [: ; 0 2 2 1&{ f 'Rosetta';'Code';':' Rosetta::Code
http://rosettacode.org/wiki/ISBN13_check_digit
ISBN13 check digit
Task Validate the check digit of an ISBN-13 code:   Multiply every other digit by  3.   Add these numbers and the other digits.   Take the remainder of this number after division by  10.   If it is  0,   the ISBN-13 check digit is correct. Use the following codes for testing:   978-1734314502       (good)   ...
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
ClearAll[ValidISBNQ] ValidISBNQ[iban_String] := Module[{i}, i = StringReplace[iban, {" " -> "", "-" -> ""}]; If[StringMatchQ[i, Repeated[DigitCharacter]], i = ToExpression /@ Characters[i]; i[[2 ;; ;; 2]] *= 3; Mod[Total[i], 10] == 0 , False ] ] ValidISBNQ["978-1734314502"] ValidISBNQ["978-17343...
http://rosettacode.org/wiki/ISBN13_check_digit
ISBN13 check digit
Task Validate the check digit of an ISBN-13 code:   Multiply every other digit by  3.   Add these numbers and the other digits.   Take the remainder of this number after division by  10.   If it is  0,   the ISBN-13 check digit is correct. Use the following codes for testing:   978-1734314502       (good)   ...
#Modula-2
Modula-2
MODULE ISBN; FROM InOut IMPORT WriteString, WriteLn; FROM Strings IMPORT Length;   PROCEDURE validISBN(s: ARRAY OF CHAR): BOOLEAN; VAR total, i, length: CARDINAL; BEGIN total := 0; length := Length(s); IF (length # 14) OR (s[3] # '-') THEN RETURN FALSE; END; FOR i := 0 TO length-1 DO ...
http://rosettacode.org/wiki/Jaro_similarity
Jaro similarity
The Jaro distance is a measure of edit distance between two strings; its inverse, called the Jaro similarity, is a measure of two strings' similarity: the higher the value, the more similar the strings are. The score is normalized such that   0   equates to no similarities and   1   is an exact match. Definition The...
#Python
Python
'''Jaro distance'''   from __future__ import division     def jaro(s, t): '''Jaro distance between two strings.''' s_len = len(s) t_len = len(t)   if s_len == 0 and t_len == 0: return 1   match_distance = (max(s_len, t_len) // 2) - 1   s_matches = [False] * s_len t_matches = [False] ...
http://rosettacode.org/wiki/Inheritance/Single
Inheritance/Single
This task is about derived types;   for implementation inheritance, see Polymorphism. Inheritance is an operation of type algebra that creates a new type from one or several parent types. The obtained type is called derived type. It inherits some of the properties of its parent types. Usually inherited properties...
#11l
11l
T Animal { } T Dog(Animal) { } T Cat(Animal) { } T Lab(Dog) { } T Collie(Dog) { }
http://rosettacode.org/wiki/Iterated_digits_squaring
Iterated digits squaring
If you add the square of the digits of a Natural number (an integer bigger than zero), you always end with either 1 or 89: 15 -> 26 -> 40 -> 16 -> 37 -> 58 -> 89 7 -> 49 -> 97 -> 130 -> 10 -> 1 An example in Python: >>> step = lambda x: sum(int(d) ** 2 for d in str(x)) >>> iterate = lambda x: x if x in [1, 89] else i...
#Pascal
Pascal
1E8 -> runtime 0..4 ms // not really measureable 1E12-> runtime 0.22 secs 1E14 -> runtime 2,7 secs 1E16 -> runtime 31,0 secs 1E18 -> runtime 354 secs // 2GByte