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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...
#Kotlin
Kotlin
interface Camera { val numberOfLenses : Int }   interface MobilePhone { fun charge(n : Int) { if (n >= 0) battery_level = (battery_level + n).coerceAtMost(100) }   var battery_level : Int }   data class CameraPhone(override val numberOfLenses : Int = 1, override var battery_level: I...
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...
#Cowgol
Cowgol
include "cowgol.coh";   # print uint32 right-aligned in column, with # thousands separators sub print_col(num: uint32, width: uint8) is # maximum integer is 4,294,967,296 for length 13, # plus one extra for the zero terminator var buf: uint8[14]; var start := &buf[0]; var last := UIToA(num, 10, &buf...
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...
#Fortran
Fortran
program nivengaps implicit none integer*8 prev /1/, gap /0/, sum /0/ integer*8 nividx /0/, niven /1/ integer gapidx /1/   character*13 idxfmt character*14 nivfmt write (*,*) 'Gap no Gap Niven index Niven number ' write (*,*) '------ --- ------...
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...
#J
J
-(_2147483647-1) 2.14748e9 2000000000 + 2000000000 4e9 _2147483647 - 2147483647 _4.29497e9 46341 * 46341 2.14749e9 (_2147483647-1) % -1 2.14748e9   -(_9223372036854775807-1) 9.22337e18 5000000000000000000+5000000000000000000 1e19 _9223372036854775807 - 9223372036854775807 _1.84467e19 303700050...
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...
#Java
Java
public class integerOverflow {   public static void main(String[] args) { System.out.println("Signed 32-bit:"); System.out.println(-(-2147483647-1)); System.out.println(2000000000 + 2000000000); System.out.println(-2147483647 - 2147483647); System.out.println(46341 * 46341); ...
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.
#Common_Lisp
Common Lisp
(defun basic-input (filename) (with-open-file (stream (make-pathname :name filename) :direction :input) (loop for line = (read-line stream nil nil) while line do (format t "~a~%" line))))
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.
#D
D
void main() { import std.stdio;   immutable fileName = "input_loop1.d";   foreach (const line; fileName.File.byLine) { pragma(msg, typeof(line)); // Prints: const(char[]) // line is a transient slice, so if you need to // retain it for later use, you have to .dup or .idup it. ...
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...
#Perl
Perl
# 20201029 added Perl programming solution   use strict; use warnings; use bigint;   use CLDR::Number 'decimal_formatter';   sub integer_sqrt { ( my $x = $_[0] ) >= 0 or die; my $q = 1; while ($q <= $x) { $q <<= 2 } my ($z, $r) = ($x, 0); while ($q > 1) { $q >>= 2; my $t = $z - $r - ...
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...
#Icon_and_Unicon
Icon and Unicon
procedure main()   texts := table() # substitute for read and parse files texts["T0.txt"] := ["it", "is", "what", "it", "is"] texts["T1.txt"] := ["what", "is", "it"] texts["T2.txt"] := ["it", "is", "a", "banana"]   every textname := key(texts) do # build index for each 'text' SII := InvertedIndex(SI...
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...
#Kotlin
Kotlin
// version 1.0.6 (intro.kt)   import java.lang.reflect.Method   val bloop = -3 val i = 4 val j = 5 val k = 6   fun main(args: Array<String>) { // get version of JVM val version = System.getProperty("java.version") if (version >= "1.6") println("The current JVM version is $version") else println("Must us...
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...
#Kotlin
Kotlin
// version 1.1.3   fun josephus(n: Int, k: Int, m: Int): Pair<List<Int>, List<Int>> { require(k > 0 && m > 0 && n > k && n > m) val killed = mutableListOf<Int>() val survived = MutableList(n) { it } var start = k - 1 outer@ while (true) { val end = survived.size - 1 var i = start ...
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"...
#zkl
zkl
fcn intersectingNumberWheelsW(wheels){ // ("A":(a,b,"C"), "C":(d,e) ...) ws:=wheels.pump(Dictionary(),fcn([(k,v)]){ return(k,Walker.cycle(v)) }); // new Dictionary Walker.zero().tweak(fcn(w,wheels){ while(1){ w=wheels[w].next(); // increment wheel w if(Int.isType(w)) return(w); } }.fp("A...
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...
#ML.2FI
ML/I
MCSKIP MT,<> MCINS %. MCDEF F WITHS (,,) AS <%WA1.%WA3.%WA2.%WA2.>
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...
#Nanoquery
Nanoquery
>nq [no file | rec1 col1] % def f(a, b, sep) ... return a + sep + sep + b ... end [no file | rec1 col1] % println 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...
#Nim
Nim
proc f(x, y, z: string) = echo x, z, z, y f("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)   ...
#Python
Python
def is_isbn13(n): n = n.replace('-','').replace(' ', '') if len(n) != 13: return False product = (sum(int(ch) for ch in n[::2]) + sum(int(ch) * 3 for ch in n[1::2])) return product % 10 == 0   if __name__ == '__main__': tests = ''' 978-1734314502 978-1734314509 978-1788399081...
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...
#Stata
Stata
ssc install jarowinkler
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...
#Swift
Swift
func jaroWinklerMatch(_ s: String, _ t: String) -> Double { let s_len: Int = s.count let t_len: Int = t.count   if s_len == 0 && t_len == 0 { return 1.0 }   if s_len == 0 || t_len == 0 { return 0.0 }   var match_distance: Int = 0   if s_len == 1 && t_len == 1 { m...
http://rosettacode.org/wiki/Increment_a_numerical_string
Increment a numerical string
Task Increment a numerical string.
#11l
11l
V next = String(Int(‘123’) + 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 |...
#Aime
Aime
void output(integer a, integer b, text condition) { o_integer(a); o_text(condition); o_integer(b); o_byte('\n'); }     integer main(void) { if (a < b) { output(a, b, " is less then "); }   if (a == b) { output(a, b, " is equal to "); }   if (a > b) { output(a, b, " is greater than...
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
#360_Assembly
360 Assembly
COPY member
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...
#Delphi
Delphi
type Animal = class(TObject) private // private functions/variables public // public functions/variables end;   Dog = class(Animal); Cat = class(Animal); Collie = class(Dog); Lab = class(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...
#DWScript
DWScript
type Animal = class(TObject) private // private functions/variables public // public functions/variables end;   type Dog = class(Animal) end; type Cat = class(Animal) end; type Collie = class(Dog) end; type Lab = class(Dog) end;
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...
#REXX
REXX
/*REXX program performs the squaring of iterated digits (until the sum equals 1 or 89).*/ parse arg n . /*obtain optional arguments from the CL*/ if n=='' | n=="," then n=10 * 1000000 /*Not specified? Then use the default.*/ !.=0; do m=1 for 9;  !.m=m**2; end /*m*/ ...
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...
#Arturo
Arturo
rank: function [arr][ if empty? arr -> return 0 from.binary "1" ++ join.with:"0" map arr 'a -> repeat "1" a ]   unrank: function [rnk][ if rnk=1 -> return [0] bn: as.binary rnk map split.by:"0" slice bn 1 dec size bn => size ]   l: [1, 2, 3, 5, 8]   print ["The initial list:" l]   r: rank l print [...
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...
#D
D
import std.stdio, std.algorithm, std.array, std.conv, std.bigint;   BigInt rank(T)(in T[] x) pure /*nothrow*/ @safe { return BigInt("0x" ~ x.map!text.join('F')); }   BigInt[] unrank(BigInt n) pure /*nothrow @safe*/ { string s; while (n) { s = "0123456789ABCDEF"[n % 16] ~ s; n /= 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...
#Clean
Clean
module IntegerSequence   import StdEnv   Start = [x \\ x <- [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...
#Clojure
Clojure
(map println (next (range)))
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...
#C
C
#include <math.h> /* HUGE_VAL */ #include <stdio.h> /* printf() */   double inf(void) { return HUGE_VAL; }   int main() { printf("%g\n", inf()); return 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...
#C.23
C#
using System;   class Program { static double PositiveInfinity() { return double.PositiveInfinity; }   static void Main() { Console.WriteLine(PositiveInfinity()); } }
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...
#C.2B.2B
C++
#include <limits>   double inf() { if (std::numeric_limits<double>::has_infinity) return std::numeric_limits<double>::infinity(); else return std::numeric_limits<double>::max(); }
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...
#Lasso
Lasso
define trait_camera => trait { require zoomfactor   provide has_zoom() => { return .zoomfactor > 0 }   }   define trait_mobilephone => trait { require brand   provide is_smart() => { return .brand == 'Apple' }   }   define cameraphone => type {   trait { import trait_camera, trait_mobilephone }   data pu...
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...
#Latitude
Latitude
Camera ::= Mixin clone. MobilePhone ::= Mixin clone.   CameraPhone ::= Object clone. Camera inject: CameraPhone. MobilePhone inject: 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...
#Lingo
Lingo
-- parent script "Camera" property resolution   on new (me) me.resolution = "1024x768" return me end   on snap (me) put "SNAP!" 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...
#Logtalk
Logtalk
:- object(camera, ...). ... :- end_object.
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...
#FreeBASIC
FreeBASIC
  Function digit_sum(n As Uinteger, sum As Ulong) As Ulong ' devuelve la suma de los dígitos de n dada la suma de los dígitos de n - 1 sum += 1 While (n > 0 And n Mod 10 = 0) sum -= 9 n = Int(n / 10) Wend Return sum End Function   Function divisible(n As Uinteger, d As Uinteger) As B...
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...
#Go
Go
package main   import "fmt"   type is func() uint64   func newSum() is { var ms is ms = func() uint64 { ms = newSum() return ms() } var msd, d uint64 return func() uint64 { if d < 9 { d++ } else { d = 0 msd = ms() } ...
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...
#jq
jq
  def compare: if type == "string" then "\n\(.)\n" else map(tostring) | .[1] as $s | .[0] | if $s == . then . + ": agrees" else $s + ": expression evaluates to " + . end end;   [ -(-2147483647-1),"2147483648"], [2000000000 + 2000000000, "4000000000"], [-2147483647 - 2147483647, "-4294967294"], [463...
http://rosettacode.org/wiki/Integer_overflow
Integer overflow
Some languages support one or more integer types of the underlying processor. This integer types have fixed size;   usually   8-bit,   16-bit,   32-bit,   or   64-bit. The integers supported by such a type can be   signed   or   unsigned. Arithmetic for machine level integers can often be done by single CPU instruct...
#Julia
Julia
using Printf S = subtypes(Signed) U = subtypes(Unsigned)   println("Integer limits:") for (s, u) in zip(S, U) @printf("%8s: [%s, %s]\n", s, typemin(s), typemax(s)) @printf("%8s: [%s, %s]\n", u, typemin(u), typemax(u)) end
http://rosettacode.org/wiki/Input_loop
Input loop
Input loop is part of Short Circuit's Console Program Basics selection. Task Read from a text stream either word-by-word or line-by-line until the stream runs out of data. The stream will have an unknown amount of data on it.
#Delphi
Delphi
program InputLoop;   {$APPTYPE CONSOLE}   uses SysUtils, Classes;   var lReader: TStreamReader; // Introduced in Delphi XE begin lReader := TStreamReader.Create('input.txt', TEncoding.Default); try while lReader.Peek >= 0 do Writeln(lReader.ReadLine); finally lReader.Free; end; end.
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.
#D.C3.A9j.C3.A0_Vu
Déjà Vu
while /= :eof dup !read-line!stdin: !print( "Read a line: " !decode!utf-8 swap ) drop !print "End of file."
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...
#Phix
Phix
with javascript_semantics include mpfr.e function isqrt(mpz x) if mpz_cmp_si(x,0)<0 then crash("Argument cannot be negative.") end if mpz q = mpz_init(1), r = mpz_init(0), t = mpz_init(), z = mpz_init_set(x) while mpz_cmp(q,x)<= 0 do mpz_mul_si(q,q,4) end wh...
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...
#J
J
require'files regex strings'   rxutf8 0 NB. support latin1 searches for this example, instead of utf8 files=:words=:buckets=:'' wordre=: rxcomp '[\w'']+' parse=: ,@:rxfrom~ wordre&rxmatches   invert=: verb define files=: files,todo=. ~.y-.files >invert1 each todo )   invert1=: verb define file=. files i.<y wor...
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...
#Lasso
Lasso
var(bloob = -26)   decimal(lasso_version(-lassoversion)) < 9.2 ? abort   var_defined('bloob') and $bloob -> isa(::integer) and lasso_tagexists('math_abs') ? math_abs($bloob)
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...
#Lingo
Lingo
put _player.productVersion -- "11.5.9"   _player.itemDelimiter="." if integer(_player.productVersion.item[1])<11 then _player.quit()
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...
#Lua
Lua
function josephus(n, k, m) local positions={} for i=1,n do table.insert(positions, i-1) end local i,j=1,1 local s='Execution order: ' while #positions>m do if j==k then s=s .. positions[i] .. ', ' table.remove(positions, i) i=i-1 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...
#OCaml
OCaml
$ ocaml Objective Caml version 3.12.1   # let f s1 s2 sep = String.concat sep [s1; ""; s2];; val f : string -> string -> string -> string = <fun> # f "Rosetta" "Code" ":";; - : string = "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)   ...
#Quackery
Quackery
[ char 0 char 9 1+ within ] is digit? ( c --> b )   [ 1 & ] is odd? ( n --> b )   [ [] swap ]'[ swap witheach [ dup nested unrot over do iff [ dip join ] else nip ] drop ] is filter ( [ --> [ )   [ 0 swap witheach [ char->n i^ odd? iff [...
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...
#Tcl
Tcl
proc jaro {s1 s2} { set l1 [string length $s1] set l2 [string length $s2] set dmax [expr {max($l1, $l2)/2 - 1}] ;# window size to scan for matches set m1 {} ;# match indices set m2 {} for {set i 0} {$i < $l1} {incr i} { set jmin [expr {$i - $dmax}] ...
http://rosettacode.org/wiki/Increment_a_numerical_string
Increment a numerical string
Task Increment a numerical string.
#8080_Assembly
8080 Assembly
org 100h jmp demo ;;; Increment the number in the $-terminated string under HL. ;;; The new string is written back to the original location. ;;; It may grow by one byte (e.g. 999 -> 1000). incstr: mvi a,'$' ; End marker lxi d,303Ah ; D='0', E='9'+1 lxi b,0 ; Find the end of the string and find the length isrch: ...
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 |...
#ALGOL_68
ALGOL 68
main: ( INT a, b; read((a, space, b, new line));   IF a <= b OR a LE b # OR a ≤ b # THEN print((a," is less or equal to ", b, new line)) FI; IF a < b OR a LT b THEN print((a," is less than ", b, new line)) ELIF a = b OR a EQ b THEN print((a," is equal to ", b, new line)) ELIF a > b OR a GT b T...
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
#6502_Assembly
6502 Assembly
;main.asm org $8000 include "foo.txt" ;eof
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
#68000_Assembly
68000 Assembly
  'file constant include : includeConstantesARM64.inc' /*******************************************/ /* Constantes */ /*******************************************/ .equ STDIN, 0 // Linux input console .equ STDOUT, 1 // linux output console .equ OPEN, 56 ...
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...
#E
E
def makeType(label, superstamps) { def stamp { to audit(audition) { for s in superstamps { audition.ask(s) } return true } } def guard { to coerce(specimen, ejector) { if (__auditedBy(stamp, specimen)) { return specimen ...
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...
#Eiffel
Eiffel
class ANIMAL 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, ...
#AWK
AWK
# usage: gawk -f Idiomatically_determine_all_the_characters_that_can_be_used_for_symbols.awk   function is_valid_identifier(id, rc) { fn = "is_valid_identifier.awk" printf("function unused(%s) { arr[%s] = 1 }\n", id, id, id) >fn printf("BEGIN { exit(0) }\n") >>fn close(fn)   rc = system("gawk -f is_va...
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...
#Ring
Ring
  nr = 1000 num = 0 for n = 1 to nr sum = 0 for m = 1 to len(string(n)) sum += pow(number(substr(string(n),m,1)),2) if sum = 89 num += 1 see "" + n + " " + sum + nl ok next next see "Total under 1000 is : " + num + nl  
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...
#Ruby
Ruby
# Count how many number chains for Natural Numbers < 10**d end with a value of 1. def iterated_square_digit(d) f = Array.new(d+1){|n| (1..n).inject(1, :*)} #Some small factorials g = -> (n) { res = n.digits.sum{|d| d*d} res==89 ? 0 : res }   #An array: table[n]==0 means that n translates to 8...
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...
#FreeBASIC
FreeBASIC
type duple A as ulongint B as ulongint end type   function two_to_one( A as ulongint, B as ulongint ) as ulongint 'converts two numbers into one dim as uinteger ret = A*A + B*B + 2*A*B - 3*A - B 'according to the table return 1 + ret/2 ' 1 2...
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...
#CLU
CLU
% This iterator will generate all integers until the built-in type % overflows. It is a signed machine-sized integer; so 64 bits on % a modern machine. After that it will raise an exception. to_infinity_and_beyond = iter () yields (int) i: int := 0 while true do i := i + 1 yield(i) end end...
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...
#Clojure
Clojure
##Inf ;; same as Double/POSITIVE_INFINITY ##-Inf ;; same as Double/NEGATIVE_INFINITY (Double/isInfinite ##Inf) ;; true
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...
#CoffeeScript
CoffeeScript
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...
#Lua
Lua
function setmetatables(t,mts) --takes a table and a list of metatables return setmetatable(t,{__index = function(self, k) --collisions are resolved in this implementation by simply taking the first one that comes along. for i, mt in ipairs(mts) do local member = mt[k] if member then return member ...
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...
#M2000_Interpreter
M2000 Interpreter
  Module CheckIt { Class Camera { Private: cameratype$ Class: module Camera (.cameratype$){ } } \\ INHERITANCE AT CODE LEVEL Class MobilePhone { Private: model$ Class: module MobilePhone (.model$) {...
http://rosettacode.org/wiki/Increasing_gaps_between_consecutive_Niven_numbers
Increasing gaps between consecutive Niven numbers
Note:   Niven   numbers are also called   Harshad   numbers.   They are also called    multidigital   numbers. Niven numbers are positive integers which are evenly divisible by the sum of its digits   (expressed in base ten). Evenly divisible   means   divisible with no remainder. Task   find the gap (differen...
#Haskell
Haskell
{-# LANGUAGE NumericUnderscores #-} import Control.Monad (guard) import Text.Printf (printf) import Data.List (intercalate, unfoldr) import Data.List.Split (chunksOf) import Data.Tuple (swap)   nivens :: [Int] nivens = [1..] >>= \n -> guard (n `rem` digitSum n == 0) >> [n] where digitSum = sum . unfoldr (\x -> guard...
http://rosettacode.org/wiki/Integer_overflow
Integer overflow
Some languages support one or more integer types of the underlying processor. This integer types have fixed size;   usually   8-bit,   16-bit,   32-bit,   or   64-bit. The integers supported by such a type can be   signed   or   unsigned. Arithmetic for machine level integers can often be done by single CPU instruct...
#Kotlin
Kotlin
// version 1.0.5-2   /* Kotlin (like Java) does not have unsigned integer types but we can simulate what would happen if we did have an unsigned 32 bit integer type using this extension function */ fun Long.toUInt(): Long = this and 0xffffffffL   @Suppress("INTEGER_OVERFLOW") fun main(args: Array<String>) { //...
http://rosettacode.org/wiki/Input_loop
Input loop
Input loop is part of Short Circuit's Console Program Basics selection. Task Read from a text stream either word-by-word or line-by-line until the stream runs out of data. The stream will have an unknown amount of data on it.
#EasyLang
EasyLang
repeat l$ = input until error = 1 print l$ .
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.
#Eiffel
Eiffel
  note description : "{ There are several examples included, including input from a text file, simple console input and input from standard input explicitly. See notes in the code for details.   Examples were compile using Eiffel Studio 6.6 with only the default class libraries. }"   class APPLICATION   create make  ...
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...
#Prolog
Prolog
%%% -*- Prolog -*- %%% %%% The Rosetta Code integer square root task, for SWI Prolog. %%%   %% pow4gtx/2 -- Find a power of 4 greater than X. pow4gtx(X, Q) :- pow4gtx(X, 1, Q), !. pow4gtx(X, A, Q) :- X < A, Q is A. pow4gtx(X, A, Q) :- A1 is A * 4, pow4gtx(X, A1, Q).   %% isqrt/2 -- Find integer squa...
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...
#Java
Java
  package org.rosettacode;   import java.io.BufferedReader; import java.io.File; import java.io.FileReader; import java.io.IOException; import java.util.ArrayList; import java.util.Arrays; import java.util.HashMap; import java.util.HashSet; import java.util.LinkedList; import java.util.List; import java.util.Map; impor...
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...
#Locomotive_Basic
Locomotive Basic
org &4000 ; program start address   push bc push de push hl push af ld bc,&df00 ; select BASIC ROM out (c),c ; (ROM 0)   ld bc,&7f86 ; make ROM accessible at &c000 out (c),c ; (RAM block 3)   ld hl,&c001 ; copy ROM version number to RAM ld de,&4040 ld bc,3 ldir   ld bc,&7f8e ; turn off ROM out (c),...
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...
#Logo
Logo
show logoversion  ; 5.6 if logoversion < 6.0 [print [too old!]]   if and [name? "a] [number? :a] [ print ifelse procedure? "abs [abs :a] [ifelse :a < 0 [minus :a] [:a]] ]
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...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
survivor[n_, k_] := Nest[Most[RotateLeft[#, k]] &, Range[0, n - 1], n - 1] survivor[41, 3]
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...
#Octave
Octave
$ octave GNU Octave, version 3.0.2 Copyright (C) 2008 John W. Eaton and others. This is free software; see the source code for copying conditions. There is ABSOLUTELY NO WARRANTY; not even for MERCHANTIBILITY or FITNESS FOR A PARTICULAR PURPOSE. For details, type `warranty'.   Octave was configured for "i586-mandriva-...
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)   ...
#Racket
Racket
#lang racket/base   (define (isbn13-check-digit-valid? s) (zero? (modulo (for/sum ((i (in-naturals)) (d (regexp-replace* #px"[^[:digit:]]" s ""))) (* (- (char->integer d) (char->integer #\0)) (if (even? i) 1 3))) 10)))   (module+ tes...
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...
#Turbo-Basic_XL
Turbo-Basic XL
  10 DIM Word_1$(20), Word_2$(20), Z$(20) 11 CLS 20 Word_1$="MARTHA" : Word_2$="MARHTA" : ? Word_1$;" - ";Word_2$ : EXEC _JWD_ : ? 30 Word_1$="DIXON" : Word_2$="DICKSONX" : ? Word_1$;" - ";Word_2$ : EXEC _JWD_ : ? 40 Word_1$="JELLYFISH" : Word_2$="SMELLYFISH" : ? Word_1$;" - ";Word_2$ : EXEC _JWD_ : ?   11000 END 12000...
http://rosettacode.org/wiki/Increment_a_numerical_string
Increment a numerical string
Task Increment a numerical string.
#8086_Assembly
8086 Assembly
cpu 8086 bits 16 section .text org 100h jmp demo ; Jump towards demo code ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;; Increment the number in the $-terminated string ;;; in [ES:DI]. The string is written back to its original ;;; location. It may grow by one byte. incnum: mov al,'$' ; F...
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 |...
#ALGOL_W
ALGOL W
begin   integer a, b;   write( "first number: " ); read( a ); write( "second number: " ); read( b );   if a < b then write( a, " is less than ", b ); if a = b then write( a, " is equal to ", b ); if a > b then write( a, " is greater than ", b );   end.
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
#AArch64_Assembly
AArch64 Assembly
  'file constant include : includeConstantesARM64.inc' /*******************************************/ /* Constantes */ /*******************************************/ .equ STDIN, 0 // Linux input console .equ STDOUT, 1 // linux output console .equ OPEN, 56 ...
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
#ACL2
ACL2
(include-book "filename")
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...
#Elena
Elena
class Animal { // ... }   class Dog : Animal { // ... }   class Lab : Dog { // ... }   class Collie : Dog { // ... }   class Cat : Animal { // ... }
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...
#F.23
F#
type Animal() = class // explicit syntax needed for empty class end   type Dog() = inherit Animal()   type Lab() = inherit Dog()   type Collie() = inherit Dog()   type Cat() = inherit Animal()
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...
#Factor
Factor
TUPLE: animal ; TUPLE: dog < animal ; TUPLE: cat < animal ; TUPLE: lab < dog ; TUPLE: collie < dog ;
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, ...
#F.23
F#
  let ``+`` = 5 printfn "%d" ``+``  
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, ...
#Factor
Factor
USING: parser see ; \ scan-word-name see
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, ...
#Go
Go
package main   import ( "fmt" "go/ast" "go/parser" "strings" "unicode" )   func isValidIdentifier(identifier string) bool { node, err := parser.ParseExpr(identifier) if err != nil { return false } ident, ok := node.(*ast.Ident) return ok && ident.Name == identifier }   type runeRanges struct { ranges []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...
#Rust
Rust
fn digit_square_sum(mut num: usize) -> usize { let mut sum = 0; while num != 0 { sum += (num % 10).pow(2); num /= 10; } sum }   fn last_in_chain(num: usize) -> usize { match num { 1 | 89 => num, _ => last_in_chain(digit_square_sum(num)), } }   fn main() { let ...
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...
#Scala
Scala
import scala.annotation.tailrec   object Euler92 extends App { override val executionStart = compat.Platform.currentTime   @tailrec private def calcRec(i: Int): Int = {   @tailrec def iter0(n: Int, total: Int): Int = if (n > 0) { val rest = n % 10 iter0(n / 10, total + rest * rest) ...
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...
#Go
Go
package main   import ( "fmt" "math/big" )   func rank(l []uint) (r big.Int) { for _, n := range l { r.Lsh(&r, n+1) r.SetBit(&r, int(n), 1) } return }   func unrank(n big.Int) (l []uint) { m := new(big.Int).Set(&n) for a := m.BitLen(); a > 0; { m.SetBit(m, a-1, 0) ...
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...
#COBOL
COBOL
IDENTIFICATION DIVISION. PROGRAM-ID. Int-Sequence.   DATA DIVISION. WORKING-STORAGE SECTION. * *> 36 digits is the largest size a numeric field can have. 01 I PIC 9(36).   PROCEDURE DIVISION. * *> Display numbers until I overflows. PERFORM VARYING I FR...
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...
#CoffeeScript
CoffeeScript
  # This very limited BCD-based collection of functions # makes it easy to count very large numbers. All arrays # start off with the ones columns in position zero. # Using arrays of decimal-based digits to model integers # doesn't make much sense for most tasks, but if you # want to keep counting forever, this does th...
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...
#Common_Lisp
Common Lisp
> (apropos "MOST-POSITIVE" :cl) MOST-POSITIVE-LONG-FLOAT, value: 1.7976931348623158D308 MOST-POSITIVE-SHORT-FLOAT, value: 3.4028172S38 MOST-POSITIVE-SINGLE-FLOAT, value: 3.4028235E38 MOST-POSITIVE-DOUBLE-FLOAT, value: 1.7976931348623158D308 MOST-POSITIVE-FIXNUM, value: 536870911   > (apropos "MOST-NEGATIVE" :cl) MOST-N...
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...
#Component_Pascal
Component Pascal
  MODULE Infinity; IMPORT StdLog;   PROCEDURE Do*; VAR x: REAL; BEGIN x := 1 / 0; StdLog.String("x:> ");StdLog.Real(x);StdLog.Ln END Do;    
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...
#Nemerle
Nemerle
interface ICamera { // ... }   class MobilePhone { // ... }   class CameraPhone: MobilePhone, ICamera { // ... }
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...
#NetRexx
NetRexx
/* NetRexx */ options replace format comments java crossref symbols binary   class RInheritMultiple public method main(args = String[]) public static iPhone = RInheritMultiple_CameraPhone() if iPhone <= RInheritMultiple_Camera then - say - 'Object' hashToString(iPhone) '['iPhone.getClass().getSimp...
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...
#J
J
  tasks=: (gap , (,:~ index))@:niven   gap=: 0 ,~ 2 -~/\ ] index=: i.@:# niven=: I.@:nivenQ@:i. nivenQ=: 0 = (|~ ([: (+/"1) 10&#.^:_1))   assert 1 0 1 -: nivenQ 10 11 12 NB. demonstrate correct niven test assert 1 = +/ 10 12 E. niven 100 NB. the sublist 10 12 occurs once in niven numbers less than 100 assert 0 1 6 9...
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...
#Java
Java
  public class NivenNumberGaps {   // Title: Increasing gaps between consecutive Niven numbers   public static void main(String[] args) { long prevGap = 0; long prevN = 1; long index = 0; System.out.println("Gap Gap Index Starting Niven"); for ( long n = 2 ; n < ...
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...
#Ksh
Ksh
  #!/bin/ksh   # Integer overflow   # # Variables: # typeset -si SHORT_INT typeset -i INTEGER typeset -li LONG_INT   ###### # main # ######   (( SHORT_INT = 2**15 -1 )) ; print "SHORT_INT (2^15 -1) = $SHORT_INT" (( SHORT_INT = 2**15 )) ; print "SHORT_INT (2^15)  : $SHORT_INT"   (( INTEGER = 2**31 -1 )) ; print " 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...
#Lingo
Lingo
#include <stdio.h>
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.
#Elena
Elena
import system'routines; import system'io; import extensions'routines;   public program() { ReaderEnumerator.new(File.assign:"file.txt").forEach(printingLn) }