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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.
#Elixir
Elixir
defmodule RC do def input_loop(stream) do case IO.read(stream, :line) do  :eof -> :ok data -> IO.write data input_loop(stream) end end end   path = hd(System.argv) File.open!(path, [:read], fn stream -> RC.input_loop(stream) end)
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...
#Python
Python
def isqrt ( x ): q = 1 while q <= x : q *= 4 z,r = x,0 while q > 1 : q /= 4 t,r = z-r-q,r/2 if t >= 0 : z,r = t,r+q return r   print ' '.join( '%d'%isqrt( n ) for n in xrange( 66 )) print '\n'.join( '{0:114,} = isqrt( 7^{1:3} )'.format( isqrt( 7**n ),n ...
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...
#jq
jq
# Given an array of [ doc, array_of_distinct_words ] # construct a lookup table: { word: array_of_docs } def inverted_index: reduce .[] as $pair ({}; $pair[0] as $doc | reduce $pair[1][] as $word (.; .[$word] += [$doc]));   def search(words): def overlap(that): . as $this | reduce that[] as $...
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...
#Logtalk
Logtalk
  :- object(my_application).   :- initialization(( check_logtalk_version, compute_predicate_if_available )).   check_logtalk_version :- % version data is available by consulting the "version_data" flag current_logtalk_flag(version_data, logtalk(Major,Minor,Patch,_)), ...
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...
#MATLAB
MATLAB
function [indAlive] = josephus(numPeople,count) % Josephus: Given a circle of numPeople individuals, with a count of count, % find the index (starting at 1) of the survivor [see Josephus Problem]   %% Definitions: % 0 = dead position % 1 = alive position % index = # of person   %% Setting up arrPeople = ones(1, n...
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...
#Oforth
Oforth
oforth --i
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...
#Ol
Ol
  $ ol Welcome to Otus Lisp 2.1-2282-27a9b6c type ',help' to help, ',quit' to end session. > (define (f head tail mid) (string-append head mid mid tail)) ;; Defined f > (f "Rosetta" "Code" ":") "Rosetta::Code" > ,quit bye-bye :/  
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...
#ooRexx
ooRexx
D:\>rexx rexxtry ? This procedure lets you interactively try REXX statements. If you run it with no parameter, or with a question mark as a parameter, it will briefly describe itself. You may also enter a REXX statement directly on the command line for immediate execution and exit. Example: rexxtry call show E...
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)   ...
#Raku
Raku
sub check-digit ($isbn) { (10 - (sum (|$isbn.comb(/<[0..9]>/)) »*» (1,3)) % 10).substr: *-1 }   { my $check = .substr(*-1); my $check-digit = check-digit .chop; say "$_ : ", $check == $check-digit ?? 'Good' !! "Bad check-digit $check; should be $check-digit" } for words < 978-173431...
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...
#VBA
VBA
  Option Explicit   Function JaroWinkler(text1 As String, text2 As String, Optional p As Double = 0.1) As Double Dim dummyChar, match1, match2 As String Dim i, f, t, j, m, l, s1, s2, limit As Integer   i = 1 Do dummyChar = Chr(i) i = i + 1 Loop Until InStr(1, text1 & text2, dummyChar, vbTextCompare) = 0   s1 = ...
http://rosettacode.org/wiki/Increment_a_numerical_string
Increment a numerical string
Task Increment a numerical string.
#AArch64_Assembly
AArch64 Assembly
  /* ARM assembly AARCH64 Raspberry PI 3B */ /* program incstring64.s */   /*******************************************/ /* Constantes file */ /*******************************************/ /* for this file see task include a file in language AArch64 assembly*/ .include "../includeConstantesAR...
http://rosettacode.org/wiki/Increment_a_numerical_string
Increment a numerical string
Task Increment a numerical string.
#ABAP
ABAP
report zz_incstring perform test using: '0', '1', '-1', '10000000', '-10000000'.   form test using iv_string type string. data: lv_int type i, lv_string type string. lv_int = iv_string + 1. lv_string = lv_int. concatenate '"' iv_string '" + 1 = "' lv_string '"' into lv_string. write / lv_string. endf...
http://rosettacode.org/wiki/Integer_comparison
Integer comparison
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 |...
#AppleScript
AppleScript
set n1 to text returned of (display dialog "Enter the first number:" default answer "") as integer set n2 to text returned of (display dialog "Enter the second number:" default answer "") as integer set msg to {n1} if n1 < n2 then set end of msg to " is less than " else if n1 = n2 then set end of msg to " is equal to...
http://rosettacode.org/wiki/Include_a_file
Include a file
Task Demonstrate the language's ability to include source code from other files. See Also Compiler/Simple file inclusion pre processor
#Action.21
Action!
INCLUDE "D2:REAL.ACT" ;from the Action! Tool Kit   PROC Main() RETURN
http://rosettacode.org/wiki/Include_a_file
Include a file
Task Demonstrate the language's ability to include source code from other files. See Also Compiler/Simple file inclusion pre processor
#Ada
Ada
with Ada.Text_IO, Another_Package; use Ada.Text_IO; -- the with-clause tells the compiler to include the Text_IO package from the Ada standard -- and Another_Package. Subprograms from these packages may be called as follows: -- Ada.Text_IO.Put_Line("some text"); -- Another_Pack...
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...
#Fancy
Fancy
class Animal { # ... }   class Dog : Animal { # ... }   class Cat : Animal { # ... }   class Lab : Dog { # ... }   class Collie : Dog { # ... }
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...
#Fantom
Fantom
class Animal { }   class Dog : Animal { }   class Cat : Animal { }   class Lab : Dog { }   class Collie : Dog { }
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...
#Forth
Forth
include 4pp/lib/foos.4pp   :: Animal class end-class {} ; :: Dog extends Animal end-extends {} ; :: Cat extends Animal end-extends {} ; :: Lab extends Dog end-extends {} ; :: Collie extends Dog end-extends {} ;
http://rosettacode.org/wiki/Idiomatically_determine_all_the_lowercase_and_uppercase_letters
Idiomatically determine all the lowercase and uppercase letters
Idiomatically determine all the lowercase and uppercase letters   (of the Latin [English] alphabet)   being used currently by a computer programming language. The method should find the letters regardless of the hardware architecture that is being used (ASCII, EBCDIC, or other). Task requirements Display the set of...
#11l
11l
print(‘Lower case: ’, end' ‘’) L(ch) ‘a’..‘z’ print(ch, end' ‘’) print() print(‘Upper case: ’, end' ‘’) L(ch) ‘A’..‘Z’ print(ch, end' ‘’) print()
http://rosettacode.org/wiki/Idiomatically_determine_all_the_characters_that_can_be_used_for_symbols
Idiomatically determine all the characters that can be used for symbols
Idiomatically determine all the characters that can be used for symbols. The word symbols is meant things like names of variables, procedures (i.e., named fragments of programs, functions, subroutines, routines), statement labels, events or conditions, and in general, anything a computer programmer can choose to name, ...
#Haskell
Haskell
varid → (small {small | large | digit | ' }) / reservedid conid → large {small | large | digit | ' } reservedid → case | class | data | default | deriving | do | else | foreign | if | import | in | infix | infixl | infixr | instance | let | module | newtype | of | then | type ...
http://rosettacode.org/wiki/Idiomatically_determine_all_the_characters_that_can_be_used_for_symbols
Idiomatically determine all the characters that can be used for symbols
Idiomatically determine all the characters that can be used for symbols. The word symbols is meant things like names of variables, procedures (i.e., named fragments of programs, functions, subroutines, routines), statement labels, events or conditions, and in general, anything a computer programmer can choose to name, ...
#J
J
a.#~1=#@;: ::0:"1 'b',.a.,.'c' 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz
http://rosettacode.org/wiki/Idiomatically_determine_all_the_characters_that_can_be_used_for_symbols
Idiomatically determine all the characters that can be used for symbols
Idiomatically determine all the characters that can be used for symbols. The word symbols is meant things like names of variables, procedures (i.e., named fragments of programs, functions, subroutines, routines), statement labels, events or conditions, and in general, anything a computer programmer can choose to name, ...
#Java
Java
import java.util.function.IntPredicate; import java.util.stream.IntStream;   public class Test { public static void main(String[] args) throws Exception { print("Java Identifier start: ", 0, 0x10FFFF, 72, Character::isJavaIdentifierStart, "%c");   print("Java Identifier part: ...
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...
#Sidef
Sidef
func digit_square_sum_iter(n) is cached {   if ((n == 1) || (n == 89)) { return n }   __FUNC__(n.digits.sum { .sqr }) }   say (1..1e6 -> count_by { digit_square_sum_iter(_) == 89 })
http://rosettacode.org/wiki/Index_finite_lists_of_positive_integers
Index finite lists of positive integers
It is known that the set of finite lists of positive integers is   countable. This means that there exists a subset of natural integers which can be mapped to the set of finite lists of positive integers. Task Implement such a mapping:   write a function     rank     which assigns an integer to any finite, arbi...
#Haskell
Haskell
import Data.List   toBase :: Int -> Integer -> [Int] toBase b = unfoldr f where f 0 = Nothing f n = let (q, r) = n `divMod` fromIntegral b in Just (fromIntegral r, q)   fromBase :: Int -> [Int] -> Integer fromBase n lst = foldr (\x r -> fromIntegral n*r + fromIntegral x) 0 lst   ------------------------------...
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...
#Common_Lisp
Common Lisp
(loop for i from 1 do (print i))
http://rosettacode.org/wiki/Infinity
Infinity
Task Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity.   Otherwise, return the largest possible po...
#D
D
auto inf() { return typeof(1.5).infinity; }   void main() {}
http://rosettacode.org/wiki/Infinity
Infinity
Task Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity.   Otherwise, return the largest possible po...
#Delphi
Delphi
Infinity = 1.0 / 0.0; NegInfinity = -1.0 / 0.0;
http://rosettacode.org/wiki/Infinity
Infinity
Task Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity.   Otherwise, return the largest possible po...
#Dyalect
Dyalect
func infinityTask() => Float.Infinity
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...
#Nim
Nim
type Camera = ref object of RootObj MobilePhone = ref object of RootObj CameraPhone = object camera: Camera phone: MobilePhone proc `is`(cp: CameraPhone, t: typedesc): bool = for field in cp.fields(): if field of t: return true var cp: CameraPhone echo(cp is Camera) echo(cp is MobilePhone)
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...
#Objective-C
Objective-C
@interface Camera : NSObject { } @end   @implementation Camera @end   @interface MobilePhone : NSObject { } @end   @implementation MobilePhone @end   @interface CameraPhone : NSObject { Camera *camera; MobilePhone *phone; } @end   @implementation CameraPhone   -(instancetype)init { if ((self = [super init])) { ...
http://rosettacode.org/wiki/Increasing_gaps_between_consecutive_Niven_numbers
Increasing gaps between consecutive Niven numbers
Note:   Niven   numbers are also called   Harshad   numbers.   They are also called    multidigital   numbers. Niven numbers are positive integers which are evenly divisible by the sum of its digits   (expressed in base ten). Evenly divisible   means   divisible with no remainder. Task   find the gap (differen...
#jq
jq
infinite | nivens
http://rosettacode.org/wiki/Increasing_gaps_between_consecutive_Niven_numbers
Increasing gaps between consecutive Niven numbers
Note:   Niven   numbers are also called   Harshad   numbers.   They are also called    multidigital   numbers. Niven numbers are positive integers which are evenly divisible by the sum of its digits   (expressed in base ten). Evenly divisible   means   divisible with no remainder. Task   find the gap (differen...
#Julia
Julia
using Formatting   function findharshadgaps(N) isharshad(i) = i % sum(digits(i)) == 0 println("Gap Index Number Index Niven Number") lastnum, lastnumidx, biggestgap = 1, 1, 0 for i in 2:N if isharshad(i) if (gap = i - lastnum) > biggestgap println(lpad(gap, 5), lpad...
http://rosettacode.org/wiki/Increasing_gaps_between_consecutive_Niven_numbers
Increasing gaps between consecutive Niven numbers
Note:   Niven   numbers are also called   Harshad   numbers.   They are also called    multidigital   numbers. Niven numbers are positive integers which are evenly divisible by the sum of its digits   (expressed in base ten). Evenly divisible   means   divisible with no remainder. Task   find the gap (differen...
#MAD
MAD
NORMAL MODE IS INTEGER   INTERNAL FUNCTION REM.(A,B) = A-A/B*B   PRINT COMMENT $ GAP NO GAP NIVEN INDEX NIVEN NUMBER$ PRINT COMMENT $ ****** *** *********** ************$ VECTOR VALUES FMT = $I6,S2,I3,S2,I11,S2,I12*$   PREV = 1 G...
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...
#Lua
Lua
assert(math.type~=nil, "Lua 5.3+ required for this test.") minint, maxint = math.mininteger, math.maxinteger print("min, max int64 = " .. minint .. ", " .. maxint) print("min-1 underflow = " .. (minint-1) .. " equals max? " .. tostring(minint-1==maxint)) print("max+1 overflow = " .. (maxint+1) .. " equals min? " ....
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...
#M2000_Interpreter
M2000 Interpreter
  Long A Try ok { A=12121221212121 } If not ok then Print Error$ 'Overflow Long Def Integer B Try ok { B=1212121212 } If not ok then Print Error$ ' Overflow Integer Def Currency C Try ok { C=121212121232934392898274327927948 } If not ok then Print Error$ ' return Overflow Long, but is overflow Curr...
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.
#Erlang
Erlang
% Implemented by Arjun Sunel -module(read_files). -export([main/0]).   main() -> Read = fun (Filename) -> {ok, Data} = file:read_file(Filename), Data end, Lines = string:tokens(binary_to_list(Read("read_files.erl")), "\n"), lists:foreach(fun (Y) -> io:format("~s~n", [Y]) end, lists:zipwith(fun(X,_)->X end, Lines, li...
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.
#ERRE
ERRE
LOOP INPUT(LINE,A$) PRINT(A$) EXIT IF <condition> ! condition to be implemented to  ! to avoid and endless loop END LOOP
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...
#Quackery
Quackery
[ dup size 3 / times [ char , swap i 1+ -3 * stuff ] dup 0 peek char , = if [ behead drop ] ] is +commas ( $ --> $ )   [ over size - space swap of swap join ] is justify ( $ n --> $ )   [ 1 [ 2dup < not while 2 << again ] 0 [ over 1 > while ...
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...
#Racket
Racket
  #lang racket   ;; Integer Square Root (using Quadratic Residue) (define (isqrt x) (define q-init  ; power of 4 greater than x (let loop ([acc 1]) (if (<= acc x) (loop (* acc 4)) acc)))   (define-values (z r q) (let loop ([z x] [r 0] [q q-init]) (if (<= q 1) (values z r 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...
#Julia
Julia
function makedoubleindex(files) idx = Dict{String, Dict}() for file in files str = lowercase(read(file, String)) words = split(str, r"\s+") for word in words if !haskey(idx, word) idx[word] = Dict{String, Int}() elseif !haskey(idx[word], file) ...
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...
#Lua
Lua
if _VERSION:sub(5) + 0 < 5.1 then print"too old" end --_VERSION is "Lua <version>".   if bloop and math.abs then print(math.abs(bloop)) end
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...
#Maple
Maple
> kernelopts( 'version' ); Maple 16.00, SUN SPARC SOLARIS, Mar 3 2012, Build ID 732982
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...
#Modula-2
Modula-2
MODULE Josephus; FROM FormatString IMPORT FormatString; FROM Terminal IMPORT WriteString,WriteLn,ReadChar;   PROCEDURE Josephus(n,k : INTEGER) : INTEGER; VAR a,m : INTEGER; BEGIN m := 0; FOR a:=1 TO n DO m := (m + k) MOD a; END; RETURN m END Josephus;   VAR buf : ARRAY[0..63] OF CHAR; n,...
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...
#Oz
Oz
declare fun {F As Bs Sep} {Append As Sep|Sep|Bs} end
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...
#PARI.2FGP
PARI/GP
f(s1,s2,sep)=Str(s1, sep, sep, s2);
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...
#Perl
Perl
$ perl -de1   Loading DB routines from perl5db.pl version 1.3 Editor support available.   Enter h or `h h' for help, or `man perldebug' for more help.   main::(-e:1): 1 DB<1> sub f {my ($s1, $s2, $sep) = @_; $s1 . $sep . $sep . $s2}   DB<2> p f('Rosetta', 'Code', ':') Rosetta::Code DB<3> q
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)   ...
#Red
Red
check_valid_isbn13: function [str] [ is_digit: charset [#"0" - #"9"] remove-each i str [not pick is_digit i] ; remove non-digits   either 13 = length? str [  ; reject strings of incorrect length sum: 0 repeat i 13 [ mul: either even? i [3] [1]  ; multiplier for odd/even digits ...
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...
#Vlang
Vlang
import math   fn jaro(str1 string, str2 string) f64 { s1_len := str1.len s2_len := str2.len if s1_len == 0 && s2_len == 0 { return 1 } if s1_len == 0 || s2_len == 0 { return 0 } match_distance := math.max<int>(s1_len,s2_len)/2 - 1   mut str1_matches := []bool{len: s1_len}...
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...
#Wren
Wren
import "/fmt" for Fmt   var jaro = Fn.new { |s1, s2| var le1 = s1.count var le2 = s2.count if (le1 == 0 && le2 == 0) return 1 if (le1 == 0 || le2 == 0) return 0 var dist = (le2 > le1) ? le2 : le1 dist = (dist/2).floor - 1 var matches1 = List.filled(le1, false) var matches2 = List.filled(...
http://rosettacode.org/wiki/Increment_a_numerical_string
Increment a numerical string
Task Increment a numerical string.
#Action.21
Action!
PROC Increment(CHAR ARRAY src,dst) INT val   val=ValI(src) val==+1 StrI(val,dst) RETURN   PROC Test(CHAR ARRAY src) CHAR ARRAY dst(10) Increment(src,dst) PrintF("%S+1=%S%E",src,dst) RETURN   PROC Main() Test("0") Test("1") Test("9999") Test("-1") Test("-2") Test("-10000") RETURN
http://rosettacode.org/wiki/Increment_a_numerical_string
Increment a numerical string
Task Increment a numerical string.
#ActionScript
ActionScript
function incrementString(str:String):String { return String(Number(str)+1); }
http://rosettacode.org/wiki/Integer_comparison
Integer comparison
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 |...
#ARM_Assembly
ARM Assembly
    /* ARM assembly Raspberry PI */ /* program comparNumber.s */   /* Constantes */ .equ BUFFERSIZE, 100 .equ STDIN, 0 @ Linux input console .equ STDOUT, 1 @ Linux output console .equ EXIT, 1 @ Linux syscall .equ READ, 3 @ Linux syscall .equ WRITE, 4 @ Linux syscall /* Initialized dat...
http://rosettacode.org/wiki/Include_a_file
Include a file
Task Demonstrate the language's ability to include source code from other files. See Also Compiler/Simple file inclusion pre processor
#ALGOL_68
ALGOL 68
PR read "file.a68" PR
http://rosettacode.org/wiki/Include_a_file
Include a file
Task Demonstrate the language's ability to include source code from other files. See Also Compiler/Simple file inclusion pre processor
#AntLang
AntLang
load["script.ant"]
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...
#Fortran
Fortran
module anim   type animal end type animal   type, extends(animal) :: dog end type dog   type, extends(animal) :: cat end type cat   type, extends(dog) :: lab end type lab   type, extends(dog) :: collie end type collie   end module anim
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...
#FreeBASIC
FreeBASIC
' FB 1.05.0 Win64   Type Animal Extends Object ' to enable virtual methods etc. if needed ' ... End Type   Type Dog Extends Animal ' ... End Type   Type Cat Extends Animal ' ... End Type   Type Lab Extends Dog ' ... End Type   Type Collie Extends Dog ' ... End Type
http://rosettacode.org/wiki/Idiomatically_determine_all_the_lowercase_and_uppercase_letters
Idiomatically determine all the lowercase and uppercase letters
Idiomatically determine all the lowercase and uppercase letters   (of the Latin [English] alphabet)   being used currently by a computer programming language. The method should find the letters regardless of the hardware architecture that is being used (ASCII, EBCDIC, or other). Task requirements Display the set of...
#Action.21
Action!
INCLUDE "D2:CHARTEST.ACT" ;from the Action! Tool Kit   PROC Main() CHAR ARRAY lower(128),upper(128) CHAR c BYTE lowerLen,upperLen   Put(125) PutE() ;clear screen   lowerLen=0 upperLen=0 FOR c=0 TO 127 DO IF IsLower(c) THEN lowerLen==+1 lower(lowerLen)=c ELSEIF IsUpper(c) THEN u...
http://rosettacode.org/wiki/Idiomatically_determine_all_the_lowercase_and_uppercase_letters
Idiomatically determine all the lowercase and uppercase letters
Idiomatically determine all the lowercase and uppercase letters   (of the Latin [English] alphabet)   being used currently by a computer programming language. The method should find the letters regardless of the hardware architecture that is being used (ASCII, EBCDIC, or other). Task requirements Display the set of...
#Ada
Ada
  with Ada.Text_IO; use Ada.Text_IO;   procedure Main is subtype Lower is Character range 'a' .. 'z'; subtype Upper is Character range 'A' .. 'Z'; begin Put ("Lower: "); for c in Lower'range loop Put (c); end loop; New_Line; Put ("Upper: "); for c in Upper'range loop Put (c); end ...
http://rosettacode.org/wiki/Idiomatically_determine_all_the_lowercase_and_uppercase_letters
Idiomatically determine all the lowercase and uppercase letters
Idiomatically determine all the lowercase and uppercase letters   (of the Latin [English] alphabet)   being used currently by a computer programming language. The method should find the letters regardless of the hardware architecture that is being used (ASCII, EBCDIC, or other). Task requirements Display the set of...
#ALGOL_68
ALGOL 68
STRING lc := ""; STRING uc := ""; FOR c FROM 0 TO max abs char DO CHAR ch := REPR c; IF is lower( ch ) THEN lc +:= ch FI; IF is upper( ch ) THEN uc +:= ch FI OD; print( ( "lower: """ + lc + """", newline ) ); print( ( "upper: """ + uc + """", newline ) )
http://rosettacode.org/wiki/Imaginary_base_numbers
Imaginary base numbers
Imaginary base numbers are a non-standard positional numeral system which uses an imaginary number as its radix. The most common is quater-imaginary with radix 2i. The quater-imaginary numeral system was first proposed by Donald Knuth in 1955 as a submission for a high school science talent search. [Ref.] Other imagi...
#11l
11l
F inv(c) V denom = c.real * c.real + c.imag * c.imag R Complex(c.real / denom, -c.imag / denom)   V QuaterImaginary_twoI = Complex(0, 2) V QuaterImaginary_invTwoI = inv(QuaterImaginary_twoI)   T QuaterImaginary String b2i   F (str) I !re:‘[0123.]+’.match(str) | str.count(‘.’) > 1 assert(0B, ‘...
http://rosettacode.org/wiki/Idiomatically_determine_all_the_characters_that_can_be_used_for_symbols
Idiomatically determine all the characters that can be used for symbols
Idiomatically determine all the characters that can be used for symbols. The word symbols is meant things like names of variables, procedures (i.e., named fragments of programs, functions, subroutines, routines), statement labels, events or conditions, and in general, anything a computer programmer can choose to name, ...
#jq
jq
[range(0;128) | [.] | implode | select(test("[A-Za-z0-9$_]"))] | add
http://rosettacode.org/wiki/Idiomatically_determine_all_the_characters_that_can_be_used_for_symbols
Idiomatically determine all the characters that can be used for symbols
Idiomatically determine all the characters that can be used for symbols. The word symbols is meant things like names of variables, procedures (i.e., named fragments of programs, functions, subroutines, routines), statement labels, events or conditions, and in general, anything a computer programmer can choose to name, ...
#Julia
Julia
  for i in 1:0x200000 - 1 Symbol("x" * Char(i)) end  
http://rosettacode.org/wiki/Idiomatically_determine_all_the_characters_that_can_be_used_for_symbols
Idiomatically determine all the characters that can be used for symbols
Idiomatically determine all the characters that can be used for symbols. The word symbols is meant things like names of variables, procedures (i.e., named fragments of programs, functions, subroutines, routines), statement labels, events or conditions, and in general, anything a computer programmer can choose to name, ...
#Kotlin
Kotlin
// version 1.1.4-3   typealias CharPredicate = (Char) -> Boolean   fun printChars(msg: String, start: Int, end: Int, limit: Int, p: CharPredicate, asInt: Boolean) { print(msg) (start until end).map { it.toChar() } .filter { p(it) } .take(limit) .for...
http://rosettacode.org/wiki/Image_noise
Image noise
Generate a random black and white   320x240   image continuously, showing FPS (frames per second). A sample image
#6502_Assembly
6502 Assembly
define sysRandom $fe   Snow: lda sysRandom  ;get a random number and #$01  ;remove all but bit 0 sta $0200,x  ;store in first section of VRAM   lda sysRandom  ;get a random number and #$01  ;remove all but bit 0 sta $0300,x  ;store in second section of VRAM   lda sysRandom  ;get a random number and #$01 ...
http://rosettacode.org/wiki/Image_convolution
Image convolution
One class of image digital filters is described by a rectangular matrix of real coefficients called kernel convoluted in a sliding window of image pixels. Usually the kernel is square K k l {\displaystyle K_{kl}} , where k, l are in the range -R,-R+1,..,R-1,R. W=2R+1 is the kernel width. The filter determine...
#Action.21
Action!
INCLUDE "H6:LOADPPM5.ACT"   DEFINE HISTSIZE="256"   PROC PutBigPixel(INT x,y BYTE col) IF x>=0 AND x<=79 AND y>=0 AND y<=47 THEN y==LSH 2 col==RSH 4 IF col<0 THEN col=0 ELSEIF col>15 THEN col=15 FI Color=col Plot(x,y) DrawTo(x,y+3) FI RETURN   PROC DrawImage(GrayImage POINTER image INT x...
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...
#Swift
Swift
import BigInt   func is89(_ n: Int) -> Bool { var n = n   while true { var s = 0   repeat { s += (n%10) * (n%10) n /= 10 } while n > 0   if s == 89 { return true } else if s == 1 { return false }   n = s } }   func iterSquare(upToPower pow: Int) { var sums = [...
http://rosettacode.org/wiki/Index_finite_lists_of_positive_integers
Index finite lists of positive integers
It is known that the set of finite lists of positive integers is   countable. This means that there exists a subset of natural integers which can be mapped to the set of finite lists of positive integers. Task Implement such a mapping:   write a function     rank     which assigns an integer to any finite, arbi...
#J
J
scrunch=:3 :0 n=.1x+>./y #.(1#~##:n),0,n,&#:n#.y )   hcnurcs=:3 :0 b=.#:y m=.b i.0 n=.#.m{.(m+1)}.b n #.inv#.(1+2*m)}.b )
http://rosettacode.org/wiki/Index_finite_lists_of_positive_integers
Index finite lists of positive integers
It is known that the set of finite lists of positive integers is   countable. This means that there exists a subset of natural integers which can be mapped to the set of finite lists of positive integers. Task Implement such a mapping:   write a function     rank     which assigns an integer to any finite, arbi...
#Java
Java
import java.math.BigInteger; import static java.util.Arrays.stream; import java.util.*; import static java.util.stream.Collectors.*;   public class Test3 { static BigInteger rank(int[] x) { String s = stream(x).mapToObj(String::valueOf).collect(joining("F")); return new BigInteger(s, 16); }   ...
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...
#Component_Pascal
Component Pascal
  MODULE IntegerSequence; IMPORT StdLog;   PROCEDURE Do*; VAR i: INTEGER; BEGIN FOR i := 0 TO MAX(INTEGER) DO; StdLog.Int(i) END; StdLog.Ln END Do;   END IntegerSequence.  
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...
#Computer.2Fzero_Assembly
Computer/zero Assembly
start: ADD one JMP start one: 1
http://rosettacode.org/wiki/Infinity
Infinity
Task Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity.   Otherwise, return the largest possible po...
#E
E
def infinityTask() { return Infinity # predefined variable holding positive infinity }
http://rosettacode.org/wiki/Infinity
Infinity
Task Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity.   Otherwise, return the largest possible po...
#Eiffel
Eiffel
  class APPLICATION inherit ARGUMENTS create make feature {NONE} -- Initialization number:REAL_64 make -- Run application. do number := 2^2000 print(number) print("%N") print(number.is_positive_infinity) print("%N") end end  
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...
#OCaml
OCaml
class camera = object (self) (*functions go here...*) end
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...
#Oforth
Oforth
Property new: Camera Property new: MobilePhone   Object Class new: CameraPhone CameraPhone is: Camera CameraPhone is: MobilePhone
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...
#ooRexx
ooRexx
  -- inherited classes must be created as mixinclasses. ::class phone mixinclass object   ::class camera mixinclass object   -- not a direct subclass of either, but inherits both ::class cameraphone inherit phone camera   -- could also be ::class cameraphone1 subclass phone inherit camera   -- or   ::class cameraphone2...
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...
#OxygenBasic
OxygenBasic
class Camera string cbuf method TakePhoto() end method method ViewPhoto() end method end class   class MobilePhone string pbuf method MakeCall() end method method TakeCall() end method end class   class CameraPhone has Camera,MobilePhone end class   CameraPhone cp   cp.ViewPhoto cp.MakeCall
http://rosettacode.org/wiki/Increasing_gaps_between_consecutive_Niven_numbers
Increasing gaps between consecutive Niven numbers
Note:   Niven   numbers are also called   Harshad   numbers.   They are also called    multidigital   numbers. Niven numbers are positive integers which are evenly divisible by the sum of its digits   (expressed in base ten). Evenly divisible   means   divisible with no remainder. Task   find the gap (differen...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
ClearAll[NivenQ] $HistoryLength = 0; NivenQ[n_Integer] := Divisible[n, Total[IntegerDigits[n]]] sel = Select[Range[100000000], NivenQ]; i = FoldPairList[{#2 > #1, Max[#1, #2]} &, 0, Differences[sel]]; gapindex = Range[Count[i, True]]; nivenindex = Pick[Range[Length[i]], i]; nivennumber = Pick[Most[sel], i]; gap = sel[[...
http://rosettacode.org/wiki/Increasing_gaps_between_consecutive_Niven_numbers
Increasing gaps between consecutive Niven numbers
Note:   Niven   numbers are also called   Harshad   numbers.   They are also called    multidigital   numbers. Niven numbers are positive integers which are evenly divisible by the sum of its digits   (expressed in base ten). Evenly divisible   means   divisible with no remainder. Task   find the gap (differen...
#Nim
Nim
import strformat   func digitsSum(n, sum: uint64): uint64 = ## Returns the sum of the digits of n given the sum of the digits of n - 1. result = sum + 1 var n = n while n > 0 and n mod 10 == 0: dec result, 9 n = n div 10   func divisible(n, d: uint64): bool {.inline.} = if (d and 1) == 0 and (n and 1)...
http://rosettacode.org/wiki/Increasing_gaps_between_consecutive_Niven_numbers
Increasing gaps between consecutive Niven numbers
Note:   Niven   numbers are also called   Harshad   numbers.   They are also called    multidigital   numbers. Niven numbers are positive integers which are evenly divisible by the sum of its digits   (expressed in base ten). Evenly divisible   means   divisible with no remainder. Task   find the gap (differen...
#Pascal
Pascal
program NivenGaps; {$IFDEF FPC} {$MODE DELPHI} {$OPTIMIZATION ON,ALL} {$ELSE} {$APPTYPE DELPHI} {$ENDIF} uses sysutils, strutils; const base = 10; type tNum = Uint64; const cntbasedigits = ((trunc(ln(High(tNum))/ln(base))+1) DIV 8 +1) *8; type tSumDigit = record sdDigits : array[...
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...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
$MaxNumber + 10^-15.954589770191003298111788092733772206160314 $MaxNumber
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...
#Nim
Nim
try: var x: int32 = -2147483647 x = -(x - 1) # Raise overflow. echo x except OverflowDefect: echo "Overflow detected"
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.
#Euphoria
Euphoria
procedure process_line_by_line(integer fn) object line while 1 do line = gets(fn) if atom(line) then exit end if -- process the line end while end procedure
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.
#F.23
F#
  let lines_of_file file = seq { use stream = System.IO.File.OpenRead file use reader = new System.IO.StreamReader(stream) while not reader.EndOfStream do yield reader.ReadLine() }  
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...
#Raku
Raku
use Lingua::EN::Numbers;   sub isqrt ( \x ) { my ( $X, $q, $r, $t ) = x, 1, 0 ; $q +<= 2 while $q ≤ $X ; while $q > 1 { $q +>= 2; $t = $X - $r - $q; $r +>= 1; if $t ≥ 0 { $X = $t; $r += $q } } $r }   say (^66)».&{ isqrt $_ }.Str ;   (1, 3…73)».&{ "7**$_: " ~ comma(isqrt 7**$_) }».say
http://rosettacode.org/wiki/Inverted_index
Inverted index
An Inverted Index is a data structure used to create full text search. Task Given a set of text files, implement a program to create an inverted index. Also create a user interface to do a search using that inverted index which returns a list of files that contain the query term / terms. The search index can be i...
#Kotlin
Kotlin
// version 1.1.51   import java.io.File   val invIndex = mutableMapOf<String, MutableList<Location>>() val fileNames = mutableListOf<String>() val splitter = Regex("""\W+""")   class Location(val fileName: String, val wordNum: Int) { override fun toString() = "{$fileName, word number $wordNum}" }   fun indexFile(...
http://rosettacode.org/wiki/Introspection
Introspection
Task verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old. check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop). Extra credit Repor...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
If[$VersionNumber < 8, Quit[]] If[NameQ["bloop"] && NameQ["Abs"], Print[Abs[bloop]]]
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...
#MATLAB_.2F_Octave
MATLAB / Octave
% convert version into numerical value v = version; v(v=='.')=' '; v = str2num(v); if v(2)>10; v(2) = v(2)/10; end; ver = v(1)+v(2)/10; if exist('OCTAVE_VERSION','builtin') if ver < 3.0, exit end; else if ver < 7.0, exit end; end   % test ...
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...
#Nanoquery
Nanoquery
def j(n, k) p = list(range(0, n-1)) i = 0 seq = {} while len(p) > 0 i = (i+k-1) % len(p) seq.append(p[i]) p.remove(i) end sur = seq[len(seq) - 1]; seq.remove(len(seq) - 1) return format("Prisoner killing order: %s\nS...
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...
#Phix
Phix
C:\Program Files (x86)\Phix>p -repl Warning: the repl is brand new, experimental, incomplete, and liable to crash! Enter a statement such as "?remainder(floor(250/8),8)" or "puts(1,"Hi")" >function f(string a,b,c) return a&c&c&b end function >?f("Rosetta","Code",":") "Rosetta::Code" >quit C:\Program Files (x86)\Phix...
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...
#Picat
Picat
Picat> cl f(X,Y,Sep) = X ++ [Sep,Sep] ++ Y. <Ctrl-D> Picat> print(f("Rosetta","Code",':')) Rosetta::Code yes
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...
#PicoLisp
PicoLisp
$ pil +
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)   ...
#REXX
REXX
/*REXX pgm validates the check digit of an ISBN─13 code (it may have embedded minuses).*/ parse arg $ /*obtain optional arguments from the CL*/ if $='' | if $="," then $= '978-1734314502 978-1734314509 978-1788399081 978-1788399083' @ISBN= "ISBN─13 code isn't" ...
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...
#zkl
zkl
//-->String of matched characters, ordered fcn _jaro(str1,str2, matchDistance){ cs:=Sink(String); foreach i,c in ([0..].zip(str1)){ str2.find(c,(0).max(i - matchDistance),i + matchDistance) : if(Void!=_) cs.write(c); } cs.close() }   fcn jaro(str1,str2){ s1Len,s2Len,matchDistance := str1.l...
http://rosettacode.org/wiki/Increment_a_numerical_string
Increment a numerical string
Task Increment a numerical string.
#Ada
Ada
S : String := "12345"; S := Ada.Strings.Fixed.Trim(Source => Integer'Image(Integer'Value(S) + 1), Side => Ada.Strings.Both);
http://rosettacode.org/wiki/Integer_comparison
Integer comparison
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 |...
#Arturo
Arturo
a: to :integer input "enter a value for a: " b: to :integer input "enter a value for b: "   if a<b [ print [ a "is less than" b ] ] if a>b [ print [ a "is greater than" b ] ] if a=b [ print [ a "is equal to" b ] ]
http://rosettacode.org/wiki/Include_a_file
Include a file
Task Demonstrate the language's ability to include source code from other files. See Also Compiler/Simple file inclusion pre processor
#Applesoft_BASIC
Applesoft BASIC
10 REMPROGRAM TWO 20 DEF FN A(X) = X * Y 30 PRINT FN A(2)   SAVE PROGRAM TWO
http://rosettacode.org/wiki/Include_a_file
Include a file
Task Demonstrate the language's ability to include source code from other files. See Also Compiler/Simple file inclusion pre processor
#ARM_Assembly
ARM Assembly
  'file constantes.inc' /************************************/ /* Constantes */ /************************************/ .equ STDOUT, 1 @ Linux output console .equ EXIT, 1 @ Linux syscall end program .equ WRITE, 4 @ Linux syscall write .equ BRK, 0x2d ...
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...
#Go
Go
package main   type animal struct { alive bool }   type dog struct { animal obedienceTrained bool }   type cat struct { animal litterBoxTrained bool }   type lab struct { dog color string }   type collie struct { dog catchesFrisbee bool }   func main() { var pet lab pet.alive...
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...
#Groovy
Groovy
class Animal{ //contents go here... }
http://rosettacode.org/wiki/Idiomatically_determine_all_the_lowercase_and_uppercase_letters
Idiomatically determine all the lowercase and uppercase letters
Idiomatically determine all the lowercase and uppercase letters   (of the Latin [English] alphabet)   being used currently by a computer programming language. The method should find the letters regardless of the hardware architecture that is being used (ASCII, EBCDIC, or other). Task requirements Display the set of...
#Arturo
Arturo
print ["lowercase letters:" `a`..`z`] print ["uppercase letters:" `A`..`Z`]