task_url stringlengths 30 116 | task_name stringlengths 2 86 | task_description stringlengths 0 14.4k | language_url stringlengths 2 53 | language_name stringlengths 1 52 | code stringlengths 0 61.9k | response_seed stringclasses 1
value | instruction_seed stringlengths 27 14.4k | _source stringclasses 1
value |
|---|---|---|---|---|---|---|---|---|
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #Perl | Perl | open(my $fh, '<', 'foobar.txt')
|| die "Could not open file: $!";
while (<$fh>)
{ # each line is stored in $_, with terminating newline
# chomp, short for chomp($_), removes the terminating newline
chomp;
process($_);
}
close $fh; | Give a code snippet in #Perl
Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Execute_Brain**** | Execute Brain**** | Execute Brain**** is an implementation of Brainf***.
Other implementations of Brainf***.
RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages.
Below are links to each of the versions of RCBF.
An implementation need only properly implement the following instructions:... | #Python | Python | [ stack ] is switch.arg ( --> [ )
[ switch.arg put ] is switch ( x --> )
[ switch.arg release ] is otherwise ( --> )
[ switch.arg share != iff ]else[ done
otherwise ]'... | Give a code snippet in #Python
Execute Brain**** is an implementation of Brainf***.
Other implementations of Brainf***.
RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages.
Below are links to each of the versions of RCBF.
An implementation need only properly imple... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Longest_string_challenge | Longest string challenge | Background
This "longest string challenge" is inspired by a problem that used to be given to students learning Icon. Students were expected to try to solve the problem in Icon and another language with which the student was already familiar. The basic problem is quite simple; the challenge and fun part came through th... | #XSLT_2.0 | XSLT 2.0 | <xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output indent="yes" encoding="UTF-8" omit-xml-declaration="yes" />
<xsl:template match="/*">
<t><xsl:copy-of select="for $l in max( for $s in s return string-length($s))
return s[string-length(.) eq $l]" /></t>
</xsl:template... | Give a code snippet in #XSLT_2.0
Background
This "longest string challenge" is inspired by a problem that used to be given to students learning Icon. Students were expected to try to solve the problem in Icon and another language with which the student was already familiar. The basic problem is quite simple; the chal... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Esthetic_numbers | Esthetic numbers | An esthetic number is a positive integer where every adjacent digit differs from its neighbour by 1.
E.G.
12 is an esthetic number. One and two differ by 1.
5654 is an esthetic number. Each digit is exactly 1 away from its neighbour.
890 is not an esthetic number. Nine and zero differ by 9.
These examples are n... | #Forth | Forth | \ Returns the next esthetic number in the given base after n, where n is an
\ esthetic number in that base or one less than a power of base.
: next_esthetic_number { n base -- n }
n 1+ base < if n 1+ exit then
n base / dup base mod
dup n base mod 1+ = if dup 1+ base < if 2drop n 2 + exit then then
drop base rec... | Give a code snippet in #Forth
An esthetic number is a positive integer where every adjacent digit differs from its neighbour by 1.
E.G.
12 is an esthetic number. One and two differ by 1.
5654 is an esthetic number. Each digit is exactly 1 away from its neighbour.
890 is not an esthetic number. Nine and zero diff... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knuth_shuffle | Knuth shuffle | The Knuth shuffle (a.k.a. the Fisher-Yates shuffle) is an algorithm for randomly shuffling the elements of an array.
Task
Implement the Knuth shuffle for an integer array (or, if possible, an array of any type).
Specification
Given an array items with indices ranging from 0 to last, the algorithm can be d... | #Lasso | Lasso | define staticarray->swap(p1::integer,p2::integer) => {
fail_if(
#p1 < 1 or #p2 < 1 or
#p1 > .size or #p2 > .size,
'invalid parameters'
)
#p1 == #p2
? return
local(tmp) = .get(#p2)
.get(#p2) = .get(#p1)
.get(#p1) = #tmp
}
define staticarray->knuthShuffle => {
... | Give a code snippet in #Lasso
The Knuth shuffle (a.k.a. the Fisher-Yates shuffle) is an algorithm for randomly shuffling the elements of an array.
Task
Implement the Knuth shuffle for an integer array (or, if possible, an array of any type).
Specification
Given an array items with indices ranging from 0 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Smith_numbers | Smith numbers | Smith numbers are numbers such that the sum of the decimal digits of the integers that make up that number is the same as the sum of the decimal digits of its prime factors excluding 1.
By definition, all primes are excluded as they (naturally) satisfy this condition!
Smith numbers are also known as joke numbers.... | #Ruby | Ruby | require "prime"
class Integer
def smith?
return false if prime?
digits.sum == prime_division.map{|pr,n| pr.digits.sum * n}.sum
end
end
n = 10_000
res = 1.upto(n).select(&:smith?)
puts "#{res.size} smith numbers below #{n}:
#{res.first(5).join(", ")},... #{res.last(5).join(", ")}" | Give a code snippet in #Ruby
Smith numbers are numbers such that the sum of the decimal digits of the integers that make up that number is the same as the sum of the decimal digits of its prime factors excluding 1.
By definition, all primes are excluded as they (naturally) satisfy this condition!
Smith numbers are a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #SQL_PL | SQL PL |
--#SET TERMINATOR @
SET SERVEROUTPUT ON@
CREATE OR REPLACE FUNCTION DIVISION(
IN NUMERATOR DECIMAL(5, 3),
IN DENOMINATOR DECIMAL(5, 3)
) RETURNS SMALLINT
BEGIN
DECLARE RET SMALLINT DEFAULT 1;
DECLARE TMP DECIMAL(5, 3);
DECLARE CONTINUE HANDLER FOR SQLSTATE '22012'
SET RET = 1;
SET RET = 0;
S... | Give a code snippet in #SQL_PL
Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Associative_array/Iteration | Associative array/Iteration | Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked ... | #C | C | using System;
using System.Collections.Generic;
namespace AssocArrays
{
class Program
{
static void Main(string[] args)
{
Dictionary<string,int> assocArray = new Dictionary<string,int>();
assocArray["Hello"] = 1;
assocArray.Add("World", 2);
a... | Give a code snippet in #C
Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Compoun... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Super-d_numbers | Super-d numbers | A super-d number is a positive, decimal (base ten) integer n such that d × nd has at least d consecutive digits d where
2 ≤ d ≤ 9
For instance, 753 is a super-3 number because 3 × 7533 = 1280873331.
Super-d numbers are also shown on MathWorld™ as super-d or super-d.
Task
Write a... | #Pascal | Pascal | program Super_D;
uses
sysutils,gmp;
var
s :ansistring;
s_comp : ansistring;
test : mpz_t;
i,j,dgt,cnt : NativeUint;
Begin
mpz_init(test);
for dgt := 2 to 9 do
Begin
//create '22' to '999999999'
i := dgt;
For j := 2 to dgt do
i := i*10+dgt;
s_comp := IntToStr(i);
writeln... | Give a code snippet in #Pascal
A super-d number is a positive, decimal (base ten) integer n such that d × nd has at least d consecutive digits d where
2 ≤ d ≤ 9
For instance, 753 is a super-3 number because 3 × 7533 = 1280873331.
Super-d numbers are also shown on MathWorld™ as super-d ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Web_server | Hello world/Web server | The browser is the new GUI !
Task
Serve our standard text Goodbye, World! to http://localhost:8080/ so that it can be viewed with a web browser.
The provided solution must start or implement a server that accepts multiple client connections and serves text as requested.
Note that starting a web browser or... | #Jsish | Jsish | prompt$ jsish
# require('Jsi_Websrv');
1.01
# Jsi_Websrv('', {server:true, port:8080, pageStr:'Goodbye, World!'});
...other terminal...
prompt$ curl http://localhost:8080/page
Goodbye, World!prompt$ curl http://localhost:8080/page
Goodbye, World! | Give a code snippet in #Jsish
The browser is the new GUI !
Task
Serve our standard text Goodbye, World! to http://localhost:8080/ so that it can be viewed with a web browser.
The provided solution must start or implement a server that accepts multiple client connections and serves text as requested.
Note... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic-geometric_mean | Arithmetic-geometric mean |
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Write a function to compute the arithmetic-geomet... | #Ada | Ada | with Ada.Text_IO, Ada.Numerics.Generic_Elementary_Functions;
procedure Arith_Geom_Mean is
type Num is digits 18; -- the largest value gnat/gcc allows
package N_IO is new Ada.Text_IO.Float_IO(Num);
package Math is new Ada.Numerics.Generic_Elementary_Functions(Num);
function AGM(A, G: Num) return Num is... | Give a code snippet in #Ada
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Write a function to ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_subsequential_sum | Greatest subsequential sum | Task
Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one.
An empty subsequence is considered to have the sum of 0; thus if all elements are negative, the result must be th... | #AutoIt | AutoIt |
Local $iArray[11] = [-1, -2, 3, 5, 6, -2, -1, 4, -4, 2, -1]
GREAT_SUB($iArray)
Local $iArray[5] = [-1, -2, -3, -4, -5]
GREAT_SUB($iArray)
Local $iArray[15] = [7, -6, -8, 5, -2, -6, 7, 4, 8, -9, -3, 2, 6, -4, -6]
GREAT_SUB($iArray)
Func GREAT_SUB($iArray)
Local $iSUM = 0, $iBEGIN_MAX = 0, $iEND_MAX = -1, $iMAX_SUM ... | Give a code snippet in #AutoIt
Task
Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one.
An empty subsequence is considered to have the sum of 0; thus if all elements are... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rename_a_file | Rename a file | Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type s... | #F.23 | F# | open System.IO
[<EntryPoint>]
let main args =
File.Move("input.txt","output.txt")
File.Move(@"\input.txt",@"\output.txt")
Directory.Move("docs","mydocs")
Directory.Move(@"\docs",@"\mydocs")
0 | Give a code snippet in #F.23
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rig... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Copy_stdin_to_stdout | Copy stdin to stdout | Create an executable file that copies stdin to stdout, or else a script that does so through the invocation of an interpreter at the command line.
| #8086_Assembly | 8086 Assembly | READ: equ 3Fh ; MS-DOS syscalls
WRITE: equ 40h
BUFSZ: equ 4000h ; Buffer size
cpu 8086
bits 16
org 100h
section .text
read: mov ah,READ ; Read into buffer
xor bx,bx ; From STDIN (file 0)
mov cx,BUFSZ
mov dx,buffer
int 21h
test ax,ax ; Did we read anything?
jz done ; If not, stop
xchg ax,cx ; Write as m... | Give a code snippet in #8086_Assembly
Create an executable file that copies stdin to stdout, or else a script that does so through the invocation of an interpreter at the command line.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Return_multiple_values | Return multiple values | Task
Show how to return more than one value from a function.
| #Erlang | Erlang | % Put this code in return_multi.erl and run it as "escript return_multi.erl"
-module(return_multi).
main(_) ->
{C, D, E} = multiply(3, 4),
io:format("~p ~p ~p~n", [C, D, E]).
multiply(A, B) ->
{A * B, A + B, A - B}.
| Give a code snippet in #Erlang
Task
Show how to return more than one value from a function.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Aliquot_sequence_classifications | Aliquot sequence classifications | An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications for non termination:
If the s... | #Vlang | Vlang | import math
const threshold = u64(1) << 47
fn index_of(s []u64, search u64) int {
for i, e in s {
if e == search {
return i
}
}
return -1
}
fn contains(s []u64, search u64) bool {
return index_of(s, search) > -1
}
fn max_of(i1 int, i2 int) int {
if i1 > i2 {
... | Give a code snippet in #Vlang
An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of... | #ERRE | ERRE | PROGRAM DINESMAN
BEGIN
! Floors are numbered 0 (ground) to 4 (top)
! "Baker, Cooper, Fletcher, Miller, and Smith live on different floors":
stmt1$="Baker<>Cooper AND Baker<>Fletcher AND Baker<>Miller AND "+"Baker<>Smith AND Cooper<>Fletcher AND Cooper<>Miller AND "+"Cooper<>Smith AND Fletcher<>Mil... | Give a code snippet in #ERRE
Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are al... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic/Integer | Arithmetic/Integer |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Genie | Genie | [indent=4]
/*
Arithmethic/Integer, in Genie
valac arithmethic-integer.gs
*/
init:int
a:int = 0
b:int = 0
if args.length > 2 do b = int.parse(args[2])
if args.length > 1 do a = int.parse(args[1])
print @"a+b: $a plus $b is $(a+b)"
print @"a-b: $a minus $b is $(a-b)"
print @"a*b: $a... | Give a code snippet in #Genie
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
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Increment_loop_index_within_loop_body | Loops/Increment loop index within loop body | Sometimes, one may need (or want) a loop which
its iterator (the index
variable) is modified within the
loop body in addition to the normal incrementation by the (do) loop structure index.
Goal
Demonstrate the best way to accomplish this.
Task
Write a loop which:
starts the index (variable... | #Go | Go | package main
import(
"golang.org/x/text/language"
"golang.org/x/text/message"
)
func isPrime(n uint64) bool {
if n % 2 == 0 {
return n == 2
}
if n % 3 == 0 {
return n == 3
}
d := uint64(5)
for d * d <= n {
if n % d == 0 {
return false
}
... | Give a code snippet in #Go
Sometimes, one may need (or want) a loop which
its iterator (the index
variable) is modified within the
loop body in addition to the normal incrementation by the (do) loop structure index.
Goal
Demonstrate the best way to accomplish this.
Task
Write a loop which:
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/SHA-256 | SHA-256 | SHA-256 is the recommended stronger alternative to SHA-1. See FIPS PUB 180-4 for implementation details.
Either by using a dedicated library or implementing the algorithm in your language, show that the SHA-256 digest of the string "Rosetta code" is: 764faf5c61ac315f1497f9dfa542713965b785e5cc2f707d6468d7d1124cdfcf
| #J | J | require '~addons/ide/qt/qt.ijs'
getsha256=: 'sha256'&gethash_jqtide_ | Give a code snippet in #J
SHA-256 is the recommended stronger alternative to SHA-1. See FIPS PUB 180-4 for implementation details.
Either by using a dedicated library or implementing the algorithm in your language, show that the SHA-256 digest of the string "Rosetta code" is: 764faf5c61ac315f1497f9dfa542713965b785e5c... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Test_a_function | Test a function |
Task
Using a well-known testing-specific library/module/suite for your language, write some tests for your language's entry in Palindrome.
If your language does not have a testing specific library well known to the language's community then state this or omit the language.
| #PureBasic | PureBasic | Macro DoubleQuote
; Needed for the Assert-Macro below
" ; " second dlbquote to prevent Rosettas misshighlighting of following code. Remove comment before execution!
EndMacro
Macro Assert(TEST,MSG="")
CompilerIf #PB_Compiler_Debugger
If Not (TEST)
If MSG<>"": Debug MSG: EndIf
... | Give a code snippet in #PureBasic
Task
Using a well-known testing-specific library/module/suite for your language, write some tests for your language's entry in Palindrome.
If your language does not have a testing specific library well known to the language's community then state this or omit the language.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #AWK | AWK |
# syntax: GAWK -f DOT_PRODUCT.AWK
BEGIN {
v1 = "1,3,-5"
v2 = "4,-2,-1"
if (split(v1,v1arr,",") != split(v2,v2arr,",")) {
print("error: vectors are of unequal lengths")
exit(1)
}
printf("%g\n",dot_product(v1arr,v2arr))
exit(0)
}
function dot_product(v1,v2, i,sum) {
for (i in v1... | Give a code snippet in #AWK
Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1] ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Thue-Morse | Thue-Morse | Task
Create a Thue-Morse sequence.
See also
YouTube entry: The Fairest Sharing Sequence Ever
YouTube entry: Math and OCD - My story with the Thue-Morse sequence
Task: Fairshare between two and more
| #Delphi | Delphi | /* Find the N'th digit in the Thue-Morse sequence */
proc nonrec tm(word n) byte:
word n2;
n2 := n;
while n2 ~= 0 do
n2 := n2 >> 1;
n := n >< n2
od;
n & 1
corp
/* Print the first 64 digits */
proc nonrec main() void:
byte i;
for i from 0 upto 63 do
write(tm(i):1)
... | Give a code snippet in #Delphi
Task
Create a Thue-Morse sequence.
See also
YouTube entry: The Fairest Sharing Sequence Ever
YouTube entry: Math and OCD - My story with the Thue-Morse sequence
Task: Fairshare between two and more
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Roots_of_a_function | Roots of a function | Task
Create a program that finds and outputs the roots of a given function, range and (if applicable) step width.
The program should identify whether the root is exact or approximate.
For this task, use: ƒ(x) = x3 - 3x2 + 2x
| #PureBasic | PureBasic | Procedure.d f(x.d)
ProcedureReturn x*x*x-3*x*x+2*x
EndProcedure
Procedure main()
OpenConsole()
Define.d StepSize= 0.001
Define.d Start=-1, stop=3
Define.d value=f(start), x=start
Define.i oldsign=Sign(value)
If value=0
PrintN("Root found at "+StrF(start))
EndIf
While x<=stop
value=f(x)
... | Give a code snippet in #PureBasic
Task
Create a program that finds and outputs the roots of a given function, range and (if applicable) step width.
The program should identify whether the root is exact or approximate.
For this task, use: ƒ(x) = x3 - 3x2 + 2x
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Return_multiple_values | Return multiple values | Task
Show how to return more than one value from a function.
| #Ruby | Ruby | def addsub(x, y)
[x + y, x - y]
end | Give a code snippet in #Ruby
Task
Show how to return more than one value from a function.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Zig-zag_matrix | Zig-zag matrix | Task
Produce a zig-zag array.
A zig-zag array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you zig-zag along the array's anti-diagonals.
For a graphical representation, see JPG zigzag (JPG uses such arrays to encode images).
For example, gi... | #D | D | int[][] zigZag(in int n) pure nothrow @safe {
static void move(in int n, ref int i, ref int j)
pure nothrow @safe @nogc {
if (j < n - 1) {
if (i > 0) i--;
j++;
} else
i++;
}
auto a = new int[][](n, n);
int x, y;
foreach (v; 0 .. n ^^ 2) {
... | Give a code snippet in #D
Task
Produce a zig-zag array.
A zig-zag array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you zig-zag along the array's anti-diagonals.
For a graphical representation, see JPG zigzag (JPG uses such arrays to encode ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Bogosort | Sorting algorithms/Bogosort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Perl | Perl | use List::Util qw(shuffle);
sub bogosort
{my @l = @_;
@l = shuffle(@l) until in_order(@l);
return @l;}
sub in_order
{my $last = shift;
foreach (@_)
{$_ >= $last or return 0;
$last = $_;}
return 1;} | Give a code snippet in #Perl
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Same_fringe | Same fringe | Write a routine that will compare the leaves ("fringe") of two binary trees to determine whether they are the same list of leaves when visited left-to-right. The structure or balance of the trees does not matter; only the number, order, and value of the leaves is important.
Any solution is allowed here, but many compu... | #Phix | Phix | --
-- demo\rosetta\Same_Fringe.exw
-- ============================
--
-- In some cases it may help to replace the single res with a table, such
-- that if you have concurrent task pairs {1,2} and {3,4} with a table of
-- result indexes ridx = {1,1,2,2}, then each updates res[ridx[tidx]]. In
-- other words if extend... | Give a code snippet in #Phix
Write a routine that will compare the leaves ("fringe") of two binary trees to determine whether they are the same list of leaves when visited left-to-right. The structure or balance of the trees does not matter; only the number, order, and value of the leaves is important.
Any solution i... | christopher/rosetta-code | |
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 |... | #BQN | BQN | Comp ← ⊑·/⟜"Greater than"‿"Equal To"‿"Lesser Than"(>∾=∾<)
⊑(/⟜⟨ "Greater than" "Equal To" "Lesser Than" ⟩>∾=∾<)
4 Comp 5
"Lesser Than"
5 Comp 5
"Equal To"
6 Comp 5
"Greater than" | Give a code snippet in #BQN
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
Co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parsing/RPN_to_infix_conversion | Parsing/RPN to infix conversion | Parsing/RPN to infix conversion
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a program that takes an RPN representation of an expression formatted as a space separated sequence of tokens and generates the equivalent expression in infix notation.... | #ALGOL_68 | ALGOL 68 |
# rpn to infix - parses an RPN expression and generates the equivalent #
# infix expression #
PROC rpn to infix = ( STRING rpn )STRING:
BEGIN
# we parse the string backwards using recursive descent #
INT rpn pos := UPB ... | Give a code snippet in #ALGOL_68
Parsing/RPN to infix conversion
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a program that takes an RPN representation of an expression formatted as a space separated sequence of tokens and generates the equiva... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hash_join | Hash join | An inner join is an operation that combines two data tables into one table, based on matching column values. The simplest way of implementing this operation is the nested loop join algorithm, but a more scalable alternative is the hash join algorithm.
Task[edit]
Implement the "hash join" algorithm, and demonstrate tha... | #EchoLisp | EchoLisp |
(define ages '((27 "Jonah") (18 "Alan") (28 "Glory") (18 "Popeye") (28 "Alan")))
(define nemesis '(("Jonah" "Whales") ("Jonah" "Spiders") ("Alan" "Ghosts") ("Alan" "Zombies") ("Glory" "Buffy")))
;; table: table name
;; source : input list
;; key-proc : procedure returning the join value ('name' in this task)
(def... | Give a code snippet in #EchoLisp
An inner join is an operation that combines two data tables into one table, based on matching column values. The simplest way of implementing this operation is the nested loop join algorithm, but a more scalable alternative is the hash join algorithm.
Task[edit]
Implement the "hash jo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ackermann_function | Ackermann function | The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
n
+
1
if
m
=
0
A
(
m
... | #VBScript | VBScript | option explicit
'~ dim depth
function ack(m, n)
'~ wscript.stdout.write depth & " "
if m = 0 then
'~ depth = depth + 1
ack = n + 1
'~ depth = depth - 1
elseif m > 0 and n = 0 then
'~ depth = depth + 1
ack = ack(m - 1, 1)
'~ depth = depth - 1
'~ elseif m > 0 and n > 0 then
else
'~ depth = depth + 1
... | Give a code snippet in #VBScript
The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{... | christopher/rosetta-code | |
http://rosettacode.org/wiki/FASTA_format | FASTA format | In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.
Task
Write a program that reads a FASTA file such as:
>Rosetta_Example_1
THERECANBENOSPACE
... | #J | J | require 'strings' NB. not needed for J versions greater than 6.
parseFasta=: ((': ' ,~ LF&taketo) , (LF -.~ LF&takeafter));._1 | Give a code snippet in #J
In bioinformatics, long character strings are often encoded in a format called FASTA.
A FASTA file can contain several strings, each identified by a name marked by a > (greater than) character at the beginning of the line.
Task
Write a program that reads a FASTA file such as:
>Rosetta_E... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Infinite | Loops/Infinite | Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within l... | #Racket | Racket |
#lang racket
;; Using recursion
(define (loop)
(displayln "SPAM")
(loop))
(loop)
;; Using a for loop
(for ([i (in-naturals)])
(displayln "SPAM"))
| Give a code snippet in #Racket
Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Align_columns | Align columns | Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, o... | #Ruby | Ruby | J2justifier = {Left: :ljust, Right: :rjust, Center: :center}
=begin
Justify columns of textual tabular input where the record separator is the newline
and the field separator is a 'dollar' character.
justification can be Symbol; (:Left, :Right, or :Center).
Return the justified output as a string
=end
def aligner(i... | Give a code snippet in #Ruby
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_concatenation | Array concatenation | Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| #11l | 11l | V arr1 = [1, 2, 3]
V arr2 = [4, 5, 6]
print(arr1 [+] arr2) | Give a code snippet in #11l
Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
Other tasks re... | #Z80_Assembly | Z80 Assembly | PrintChar equ &BB5A ;Amstrad CPC BIOS call, prints the ascii code in the accumulator to the screen.
org &8000
ld b,5 ; repeat 5 times
loop:
call PrintImmediate
byte "ha",0
djnz loop
ret ; return to basic
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
PrintImmediate:
pop h... | Give a code snippet in #Z80_Assembly
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Line_printer | Hello world/Line printer | Task
Cause a line printer attached to the computer to print a line containing the message: Hello World!
Note
A line printer is not the same as standard output.
A line printer was an older-style printer which prints one line at a time to a continuous ream of paper.
With some systems, a line printer can be... | #PL.2FI | PL/I |
hello: procedure options(main);
put skip list('Hello world.');
end hello; | Give a code snippet in #PL.2FI
Task
Cause a line printer attached to the computer to print a line containing the message: Hello World!
Note
A line printer is not the same as standard output.
A line printer was an older-style printer which prints one line at a time to a continuous ream of paper.
With som... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Reduced_row_echelon_form | Reduced row echelon form | Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this wil... | #BASIC256 | BASIC256 | arraybase 1
global matrix
dim matrix = {{1, 2, -1, -4}, {2, 3, -1, -11}, { -2, 0, -3, 22}}
call RREF (matrix)
for row = 1 to 3
for col = 1 to 4
if matrix[row, col] = 0 then
print "0"; chr(9);
else
print matrix[row, col]; chr(9);
end if
next
print
next
end
... | Give a code snippet in #BASIC256
Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is conven... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Population_count | Population count | Population count
You are encouraged to solve this task according to the task description, using any language you may know.
The population count is the number of 1s (ones) in the binary representation of a non-negative integer.
Population count is also known as:
pop count
popcount
sideways sum
... | #Phix | Phix | with javascript_semantics
function pop_count(atom n)
if n<0 then ?9/0 end if
integer res = 0
while n!=0 do
res += and_bits(n,1)
n = floor(n/2)
end while
return res
end function
printf(1,"3^x pop_counts:%v\n",{apply(apply(true,power,{3,tagset(29,0)}),pop_count)})
procedure eo(inte... | Give a code snippet in #Phix
Population count
You are encouraged to solve this task according to the task description, using any language you may know.
The population count is the number of 1s (ones) in the binary representation of a non-negative integer.
Population count is also known as:
pop count
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/99_bottles_of_beer | 99 bottles of beer | Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
98 bottles of beer
Take one dow... | #BCPL | BCPL | get "libhdr"
let number(n) be
test n=0
then writes("No more")
else writen(n)
let plural(n) be
test n=1
then writes(" bottle")
else writes(" bottles")
let bottles(n) be
$( number(n)
plural(n)
$)
let verse(n) be
$( bottles(n)
writes(" of beer on the wall,*N")
... | Give a code snippet in #BCPL
Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
98 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rare_numbers | Rare numbers | Definitions and restrictions
Rare numbers are positive integers n where:
n is expressed in base ten
r is the reverse of n (decimal digits)
n must be non-palindromic (n ≠ r)
(n+r) is the sum
(n-r) is the difference and must be positive
the sum and the ... | #Java | Java | import java.time.Duration;
import java.time.LocalDateTime;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicReference;
public class RareNumbers {
... | Give a code snippet in #Java
Definitions and restrictions
Rare numbers are positive integers n where:
n is expressed in base ten
r is the reverse of n (decimal digits)
n must be non-palindromic (n ≠ r)
(n+r) is the sum
(n-r) is the difference and must be pos... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Truncatable_primes | Truncatable primes | A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number.
Examples
The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime.
The number 7393 is a right-truncatable prime as the numbers 7393, 7... | #Haskell | Haskell | import Data.Numbers.Primes(primes, isPrime)
import Data.List
import Control.Arrow
primes1e6 = reverse. filter (notElem '0'. show) $ takeWhile(<=1000000) primes
rightT, leftT :: Int -> Bool
rightT = all isPrime. takeWhile(>0). drop 1. iterate (`div`10)
leftT x = all isPrime. takeWhile(<x).map (x`mod`) $ iterate (*10... | Give a code snippet in #Haskell
A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number.
Examples
The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime.
The number 7393 is a right-truncat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Statistics/Basic | Statistics/Basic | Statistics is all about large groups of numbers.
When talking about a set of sampled data, most frequently used is their mean value and standard deviation (stddev).
If you have set of data
x
i
{\displaystyle x_{i}}
where
i
=
1
,
2
,
…
,
n
{\displaystyle i=1,2,\ldots ,n\,\!}
, the mean is
x
¯... | #Python | Python | def sd1(numbers):
if numbers:
mean = sum(numbers) / len(numbers)
sd = (sum((n - mean)**2 for n in numbers) / len(numbers))**0.5
return sd, mean
else:
return 0, 0
def sd2(numbers):
if numbers:
sx = sxx = n = 0
for x in numbers:
sx += x
... | Give a code snippet in #Python
Statistics is all about large groups of numbers.
When talking about a set of sampled data, most frequently used is their mean value and standard deviation (stddev).
If you have set of data
x
i
{\displaystyle x_{i}}
where
i
=
1
,
2
,
…
,
n
{\displaystyle i=1,2,\ldots ,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_case | String case | Task
Take the string alphaBETA and demonstrate how to convert it to:
upper-case and
lower-case
Use the default encoding of a string literal or plain ASCII if there is no string literal in your language.
Note: In some languages alphabets toLower and toUpper is not reversable.
Show any additional... | #mIRC_Scripting_Language | mIRC Scripting Language | echo -ag $upper(alphaBETA)
echo -ag $lower(alphaBETA) | Give a code snippet in #mIRC_Scripting_Language
Task
Take the string alphaBETA and demonstrate how to convert it to:
upper-case and
lower-case
Use the default encoding of a string literal or plain ASCII if there is no string literal in your language.
Note: In some languages alphabets toLower an... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Long_literals,_with_continuations | Long literals, with continuations | This task is about writing a computer program that has long literals (character
literals that may require specifying the words/tokens on more than one (source)
line, either with continuations or some other method, such as abutments or
concatenations (or some other mechanisms).
The literal is to be in the form ... | #Nim | Nim | import strutils
const RevDate = "2021-02-05"
# We use the concatenation operator "&" to assemble the strings.
# This is done at compile time and so the result is a long literal.
const ElementString =
"hydrogen helium lithium beryllium boron carbon nitrogen oxygen fluorine " &
"neon sodium magnesium aluminum sil... | Give a code snippet in #Nim
This task is about writing a computer program that has long literals (character
literals that may require specifying the words/tokens on more than one (source)
line, either with continuations or some other method, such as abutments or
concatenations (or some other mechanisms).
The ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #Factor | Factor | : recurse ( n -- n ) 1 + recurse ;
0 recurse | Give a code snippet in #Factor
Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| christopher/rosetta-code | |
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 |... | #Seed7 | Seed7 | $ include "seed7_05.s7i";
const proc: main is func
local
var integer: a is 0;
var integer: b is 0;
begin
readln(a);
readln(b);
if a < b then
writeln(a <& " is less than " <& b);
end if;
if a = b then
writeln(a <& " is equal to " <& b);
end if;
if a > b then
... | Give a code snippet in #Seed7
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
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-decimal_radices/Convert | Non-decimal radices/Convert | Number base conversion is when you express a stored integer in an integer base, such as in octal (base 8) or binary (base 2). It also is involved when you take a string representing a number in a given base and convert it to the stored integer form. Normally, a stored integer is in binary, but that's typically invisibl... | #LFE | LFE |
> (: erlang list_to_integer '"1a" 16)
26
> #x1a
26
> (: erlang integer_to_list 26 16)
"1A"
> (: erlang list_to_integer '"101110111000" 2)
3000
> #b101110111000
3000
> (: erlang integer_to_list 3000 2)
"101110111000"
| Give a code snippet in #LFE
Number base conversion is when you express a stored integer in an integer base, such as in octal (base 8) or binary (base 2). It also is involved when you take a string representing a number in a given base and convert it to the stored integer form. Normally, a stored integer is in binary, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_digits_of_an_integer | Sum digits of an integer | Task
Take a Natural Number in a given base and return the sum of its digits:
110 sums to 1
123410 sums to 10
fe16 sums to 29
f0e16 sums to 29
| #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Function SumDigits(number As Integer, nBase As Integer) As Integer
If number < 0 Then number = -number ' convert negative numbers to positive
If nBase < 2 Then nBase = 2 ' nBase can't be less than 2
Dim As Integer sum = 0
While number > 0
sum += number Mod nBase
number \= nBase
... | Give a code snippet in #FreeBASIC
Task
Take a Natural Number in a given base and return the sum of its digits:
110 sums to 1
123410 sums to 10
fe16 sums to 29
f0e16 sums to 29
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Variadic_function | Variadic function | Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
Related task
Call a function... | #Nemerle | Nemerle | using System;
using System.Console;
module Variadic
{
PrintAll (params args : array[object]) : void
{
foreach (arg in args) WriteLine(arg);
}
Main() : void
{
PrintAll("test", "rosetta code", 123, 5.6, DateTime.Now);
}
} | Give a code snippet in #Nemerle
Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Topological_sort | Topological sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #C.23 | C# |
namespace Algorithms
{
using System;
using System.Collections.Generic;
using System.Linq;
public class TopologicalSorter<ValueType>
{
private class Relations
{
public int Dependencies = 0;
public HashSet<ValueType> Dependents = new HashSet<ValueType>();
... | Give a code snippet in #C.23
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #OpenEdge.2FProgress | OpenEdge/Progress | MESSAGE
CHR(97) SKIP
ASC("a")
VIEW-AS ALERT-BOX. | Give a code snippet in #OpenEdge.2FProgress
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of U... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rate_counter | Rate counter | Of interest is the code that performs the actual measurements. Any other code (such as job implementation or dispatching) that is required to demonstrate the rate tracking is helpful, but not the focus.
Multiple approaches are allowed (even preferable), so long as they can accomplish these goals:
Run N seconds worth... | #J | J | x (6!:2) y | Give a code snippet in #J
Of interest is the code that performs the actual measurements. Any other code (such as job implementation or dispatching) that is required to demonstrate the rate tracking is helpful, but not the focus.
Multiple approaches are allowed (even preferable), so long as they can accomplish these g... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Undefined_values | Undefined values | #Kotlin | Kotlin | // version 1.1.2
class SomeClass
class SomeOtherClass {
lateinit var sc: SomeClass
fun initialize() {
sc = SomeClass() // not initialized in place or in constructor
}
fun printSomething() {
println(sc) // 'sc' may not have been initialized at this point
}
fun someFun... | Give a code snippet in #Kotlin
| christopher/rosetta-code | ||
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identif... | #Wren | Wren | var a = 3
var b = 2
var delta = a - b // ok
var Δ = delta // not ok | Give a code snippet in #Wren
Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #FutureBasic | FutureBasic | window 1
local fn RandomZeroToOne as double
double result
cln result = (double)( (rand() % 100000 ) * 0.00001 );
end fn = result
local fn RandomGaussian as double
double r = fn RandomZeroToOne
end fn = 1 + .5 * ( sqr( -2 * log(r) ) * cos( 2 * pi * r ) )
long i
double mean, std, a(1000)
for i = 1 to 1000
... | Give a code snippet in #FutureBasic
Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
R... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Word_frequency | Word frequency | Task
Given a text file and an integer n, print/display the n most
common words in the file (and the number of their occurrences) in decreasing frequency.
For the purposes of this task:
A word is a sequence of one or more contiguous letters.
You are free to define what a letter is.
Undersc... | #Liberty_BASIC | Liberty BASIC | dim words$(100000,2)'words$(a,1)=the word, words$(a,2)=the count
dim lines$(150000)
open "135-0.txt" for input as #txt
while EOF(#txt)=0 and total < 150000
input #txt, lines$(total)
total=total+1
wend
for a = 1 to total
token$ = "?"
index=0
new=0
while token$ <> ""
new=0
index = ... | Give a code snippet in #Liberty_BASIC
Task
Given a text file and an integer n, print/display the n most
common words in the file (and the number of their occurrences) in decreasing frequency.
For the purposes of this task:
A word is a sequence of one or more contiguous letters.
You are free to d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Bubble_sort | Sorting algorithms/Bubble sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Symsyn | Symsyn |
x : 23 : 15 : 99 : 146 : 3 : 66 : 71 : 5 : 23 : 73 : 19
bubble_sort param index size
+ index size limit
lp
changes
- limit
index i
if i < limit
+ 1 i ip1
if base.i > base.ip1
swap base.i base.ip1
+ changes
endif
+ i
goif
endif
if changes > 0
go lp
endif
retu... | Give a code snippet in #Symsyn
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/The_Twelve_Days_of_Christmas | The Twelve Days of Christmas | Task
Write a program that outputs the lyrics of the Christmas carol The Twelve Days of Christmas.
The lyrics can be found here.
(You must reproduce the words in the correct order, but case, format, and punctuation are left to your discretion.)
Other tasks related to string operations:
Metrics
Array length
Stri... | #Common_Lisp | Common Lisp | let
((gifts '("A partridge in a pear tree." "Two turtle doves, and"
"Three French hens," "Four calling birds,"
"Five gold rings," "Six geese a-laying,"
"Seven swans a-swimming," "Eight maids a-milking,"
"Nine ladies dancing," "Ten lords a-... | Give a code snippet in #Common_Lisp
Task
Write a program that outputs the lyrics of the Christmas carol The Twelve Days of Christmas.
The lyrics can be found here.
(You must reproduce the words in the correct order, but case, format, and punctuation are left to your discretion.)
Other tasks related to string ope... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Walk_a_directory/Recursively | Walk a directory/Recursively | Task
Walk a given directory tree and print files matching a given pattern.
Note: This task is for recursive methods. These tasks should read an entire directory tree, not a single directory.
Note: Please be careful when running any code examples found here.
Related task
Walk a directory/Non-recursively ... | #Ada | Ada | with Ada.Directories; use Ada.Directories;
with Ada.Text_IO;
procedure Test_Directory_Walk is
procedure Walk (Name : String; Pattern : String) is
procedure Print (Item : Directory_Entry_Type) is
begin
Ada.Text_IO.Put_Line (Full_Name (Item));
end Print;
procedure Walk (Item : Direc... | Give a code snippet in #Ada
Task
Walk a given directory tree and print files matching a given pattern.
Note: This task is for recursive methods. These tasks should read an entire directory tree, not a single directory.
Note: Please be careful when running any code examples found here.
Related task
Walk a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Do-while | Loops/Do-while | Start with a value at 0. Loop while value mod 6 is not equal to 0.
Each time through the loop, add 1 to the value then print it.
The loop must execute at least once.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loo... | #AArch64_Assembly | AArch64 Assembly |
/* ARM assembly AARCH64 Raspberry PI 3B */
/* program loopdowhile64.s */
/*******************************************/
/* Constantes file */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly*/
.include "../includeConstantes... | Give a code snippet in #AArch64_Assembly
Start with a value at 0. Loop while value mod 6 is not equal to 0.
Each time through the loop, add 1 to the value then print it.
The loop must execute at least once.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_common_divisor | Greatest common divisor | Greatest common divisor
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Find the greatest common divisor (GCD) of two integers.
Greatest common divisor is also known as greatest common factor (gcf) and greatest common measure.
Related tas... | #Fermat | Fermat | GCD(a,b) | Give a code snippet in #Fermat
Greatest common divisor
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Find the greatest common divisor (GCD) of two integers.
Greatest common divisor is also known as greatest common factor (gcf) and greates... | christopher/rosetta-code | |
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.
| #Frink | Frink | while (line = readStdin[]) != undef
println[line]
| Give a code snippet in #Frink
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.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Insertion_sort | Sorting algorithms/Insertion sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #PHP | PHP | function insertionSort(&$arr){
for($i=0;$i<count($arr);$i++){
$val = $arr[$i];
$j = $i-1;
while($j>=0 && $arr[$j] > $val){
$arr[$j+1] = $arr[$j];
$j--;
}
$arr[$j+1] = $val;
}
}
$arr = array(4,2,1,6,9,3,8,7);
insertionSort($arr);
echo implode(',',$arr); | Give a code snippet in #PHP
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Last_Friday_of_each_month | Last Friday of each month | Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24
2012-03-30
2012-04-27
2012-05-25
20... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols nobinary
import java.text.
runSample(arg)
return
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method lastFridayByLib(year) public static
cal = GregorianCalendar(year, 0, 1)
loop mon over DateFormatSymbo... | Give a code snippet in #NetRexx
Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24
20... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Command-line_arguments | Command-line arguments | Command-line arguments is part of Short Circuit's Console Program Basics selection.
Scripted main
See also Program name.
For parsing command line arguments intelligently, see Parsing command-line arguments.
Example command line:
myprogram -c "alpha beta" -h "gamma"
| #Cowgol | Cowgol | include "cowgol.coh";
include "argv.coh";
ArgvInit();
var i: uint8 := 0;
loop
var arg := ArgvNext();
if arg == 0 as [uint8] then break; end if;
i := i + 1;
print_i8(i);
print(": '");
print(arg);
print("'\n");
end loop; | Give a code snippet in #Cowgol
Command-line arguments is part of Short Circuit's Console Program Basics selection.
Scripted main
See also Program name.
For parsing command line arguments intelligently, see Parsing command-line arguments.
Example command line:
myprogram -c "alpha beta" -h "gamma"
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Loop_over_multiple_arrays_simultaneously | Loop over multiple arrays simultaneously | Task
Loop over multiple arrays (or lists or tuples or whatever they're called in
your language) and display the i th element of each.
Use your language's "for each" loop if it has one, otherwise iterate
through the collection in order with some other loop.
For this example, loop over the arrays:
... | #Haxe | Haxe | using Lambda;
using Std;
class Main
{
static function main()
{
var a = ['a', 'b', 'c'];
var b = ['A', 'B', 'C'];
var c = [1, 2, 3];
//Find smallest array
var len = [a, b, c]
.map(function(a) return a.length)
.fold(Math.min, 0x0FFFFFFF)
.int();
for (i in 0...len)
Sys.println(a[i] + b[... | Give a code snippet in #Haxe
Task
Loop over multiple arrays (or lists or tuples or whatever they're called in
your language) and display the i th element of each.
Use your language's "for each" loop if it has one, otherwise iterate
through the collection in order with some other loop.
For this examp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/A%2BB | A+B | A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated by space(s):
(
−
1000
≤... | #8th | 8th | gets dup . space eval n:+ . cr | Give a code snippet in #8th
A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dragon_curve | Dragon curve |
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by a left dragon, at 90-degree an... | #Lambdatalk | Lambdatalk |
{def dcr
{lambda {:step :length}
{let { {:step {- :step 1}}
{:length {/ :length 1.41421}}
} {if {> :step 0}
then T45
{dcr :step :length}
T-90
{dcl :step :length}
T45
else T45
M:length
T-90
... | Give a code snippet in #Lambdatalk
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon follow... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_an_array_of_composite_structures | Sort an array of composite structures |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #ALGOL_68 | ALGOL 68 | MODE SORTSTRUCT = PERSON;
OP < = (PERSON a,b)BOOL: age OF a < age OF b;
PR READ "prelude/sort.a68" PR;
MODE PERSON = STRUCT (STRING name, INT age);
FORMAT person repr = $"Name: "g", Age: "g(0)l$;
[]SORTSTRUCT person = (("joe", 120), ("foo", 31), ("bar", 51));
printf((person repr, shell sort(person), $l$)) | Give a code snippet in #ALGOL_68
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/Flood_fill | Bitmap/Flood fill | Implement a flood fill.
A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the vall... | #Racket | Racket |
#lang racket
(require racket/draw)
;; flood-fill: bitmap<%> number number color color -> void
;; An example of flood filling a bitmap.
;;
;; We'll use a raw, byte-oriented interface here for demonstration
;; purposes. Racket does provide get-pixel and set-pixel functions
;; which work on color% structures rather... | Give a code snippet in #Racket
Implement a flood fill.
A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point toward... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Compound_data_type | Compound data type |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Task
Create a compound data type:
Point(x,y)
A compound data type is one that holds multiple independent values.
Related task
Enumeration
S... | #Bracmat | Bracmat | ( ( Point
= (x=)
(y=)
(new=.!arg:(?(its.x).?(its.y)))
)
& new$(Point,(3.4)):?pt
& out$(!(pt..x) !(pt..y))
{ Show independcy by changing x, but not y }
& 7:?(pt..x)
& out$(!(pt..x) !(pt..y))
); | Give a code snippet in #Bracmat
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Task
Create a compound data type:
Point(x,y)
A compound data type is one that holds multiple independent values.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tau_function | Tau function | Given a positive integer, count the number of its positive divisors.
Task
Show the result for the first 100 positive integers.
Related task
Tau number
| #Haskell | Haskell | tau :: Integral a => a -> a
tau n | n <= 0 = error "Not a positive integer"
tau n = go 0 (1, 1)
where
yo i = (i, i * i)
go r (i, ii)
| n < ii = r
| n == ii = r + 1
| 0 == mod n i = go (r + 2) (yo $ i + 1)
| otherwise = go r (yo $ i + 1)
main = print $ map tau [1..100] | Give a code snippet in #Haskell
Given a positive integer, count the number of its positive divisors.
Task
Show the result for the first 100 positive integers.
Related task
Tau number
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Perlin_noise | Perlin noise | The Perlin noise is a kind of gradient noise invented by Ken Perlin around the end of the twentieth century and still currently heavily used in computer graphics, most notably to procedurally generate textures or heightmaps.
The Perlin noise is basically a pseudo-random mapping of
R
d
... | #J | J | band=:17 b.
ImprovedNoise=:3 :0
'x y z'=. y
X=. (<. x) band 255
Y=. (<. y) band 255
Z=. (<. z) band 255
x=. x-<.!.0 x
y=. y-<.!.0 y
z=. z-<.!.0 z
u=. fade x
v=. fade y
w=. fade z
A=. (p{~X)+Y
AA=.(p{~A)+Z
AB=.(p{~A+1)+Z
B=. (p{~X+1)+Y
BA=.(p{~B)+Z
BB=.(p{~B+1)+Z
t1=. (grad(p{~BB+1),(... | Give a code snippet in #J
The Perlin noise is a kind of gradient noise invented by Ken Perlin around the end of the twentieth century and still currently heavily used in computer graphics, most notably to procedurally generate textures or heightmaps.
The Perlin noise is basically a pseudo-random m... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_squares | Sum of squares | Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| #ALGOL_W | ALGOL W | begin
% procedure to sum the elements of a vector. As the procedure can't find %
% the bounds of the array for itself, we pass them in lb and ub %
real procedure sumSquares ( real array vector ( * )
; integer value lb
; integer value ub... | Give a code snippet in #ALGOL_W
Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| christopher/rosetta-code | |
http://rosettacode.org/wiki/File_size | File size | Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| #AutoHotkey | AutoHotkey | FileGetSize, FileSize, input.txt ; Retrieve the size in bytes.
MsgBox, Size of input.txt is %FileSize% bytes
FileGetSize, FileSize, \input.txt, K ; Retrieve the size in Kbytes.
MsgBox, Size of \input.txt is %FileSize% Kbytes | Give a code snippet in #AutoHotkey
Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Use_another_language_to_call_a_function | Use another language to call a function | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
This task is inverse to the task Call foreign language function. Consider the following C program:
#include <stdio.h>
extern int Query (char * Data, size_t * Length);
int main (i... | #Delphi | Delphi |
function Query(Buffer: PChar; var Size: Int64): LongBool;
const
Text = 'Hello World!';
begin
If not Assigned(Buffer) Then
begin
Size := 0;
Result := False;
Exit;
end;
If Size < Length(Text) Then
begin
Size := 0;
Result := False;
Exit;
end;
... | Give a code snippet in #Delphi
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
This task is inverse to the task Call foreign language function. Consider the following C program:
#include <stdio.h>
extern int Query (char * Data,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Evolutionary_algorithm | Evolutionary algorithm | Starting with:
The target string: "METHINKS IT IS LIKE A WEASEL".
An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent).
A fitness function that computes the ‘closeness’ of its argument to the target string.... | #8086_Assembly | 8086 Assembly | bits 16
cpu 8086
MRATE: equ 26 ; Mutation rate (MRATE/256)
COPIES: equ 100 ; Amount of copies to make
gettim: equ 02Ch ; MS-DOS get time function
pstr: equ 9 ; MS-DOS print string
section .text
org 100h
;;; Use MS-DOS time to set random seed
mov ah,gettim
int 21h
mov [rnddat],cx
mov [rnddat+2],dx
;;; Make ... | Give a code snippet in #8086_Assembly
Starting with:
The target string: "METHINKS IT IS LIKE A WEASEL".
An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent).
A fitness function that computes the ‘closeness... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Semiprime | Semiprime | Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers.
Semiprimes are also known as:
semi-primes
biprimes
bi-primes
2-almost primes
or simply: P2
Example
1679 = 23 × 73
(This particular number was chosen as the length of the Arecib... | #C | C | #include <stdio.h>
int semiprime(int n)
{
int p, f = 0;
for (p = 2; f < 2 && p*p <= n; p++)
while (0 == n % p)
n /= p, f++;
return f + (n > 1) == 2;
}
int main(void)
{
int i;
for (i = 2; i < 100; i++)
if (semiprime(i)) printf(" %d", i);
putchar('\n');
return 0;
} | Give a code snippet in #C
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers.
Semiprimes are also known as:
semi-primes
biprimes
bi-primes
2-almost primes
or simply: P2
Example
1679 = 23 × 73
(This particular number was chosen ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/XML/Input | XML/Input | Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M" DateOfBirth="1990-03-04" /... | #AWK | AWK | function parse_buf()
{
if ( match(buffer, /<Student[ \t]+[^>]*Name[ \t]*=[ \t]*"([^"]*)"/, mt) != 0 ) {
students[mt[1]] = 1
}
buffer = ""
}
BEGIN {
FS=""
mode = 0
buffer = ""
li = 1
}
mode==1 {
for(i=1; i <= NF; i++) {
buffer = buffer $i
if ( $i == ">" ) {
mode = 0;
b... | Give a code snippet in #AWK
Given the following XML fragment, extract the list of student names using whatever means desired. If the only viable method is to use XPath, refer the reader to the task XML and XPath.
<Students>
<Student Name="April" Gender="F" DateOfBirth="1989-01-02" />
<Student Name="Bob" Gender="M... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Maze_generation | Maze generation |
This page uses content from Wikipedia. The original article was at Maze generation algorithm. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Generate and show a maze, using the simple Depth... | #Ol | Ol |
; maze generation
(import (otus random!))
(define WIDTH 30)
(define HEIGHT 8)
(define maze
(map (lambda (?)
(repeat #b01111 WIDTH)) ; 0 - unvisited, 1111 - all walls exists
(iota HEIGHT)))
(define (at x y)
(list-ref (list-ref maze y) x))
(define (unvisited? x y)
(if (and (< -1 x WIDTH) (< ... | Give a code snippet in #Ol
This page uses content from Wikipedia. The original article was at Maze generation algorithm. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Generate and show a ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Soundex | Soundex | Soundex is an algorithm for creating indices for words based on their pronunciation.
Task
The goal is for homophones to be encoded to the same representation so that they can be matched despite minor differences in spelling (from the soundex Wikipedia article).
Caution
There is a major issue in many of the ... | #BQN | BQN | ToUpper ← -⟜(32×1="a{"⊸⍋)
Split ← ((⊢-˜+`׬)∘=⊔⊢)
replace ← ⟨
"AEIOUYHW"
"BFPV"
"CGJKQSXZ"
"DT"
"L"
"MN"
"R"
⟩
Soundex ← ⊑∾{'0'+»⟜0‿0‿0⊑¨0⊸≠⊸/(0≠⊑)⊸↓⊑¨(¯1+·+`1»≠⟜«)⊸⊔∾/¨<˘⍉>replace∊˜¨<ToUpper 𝕩}
names ← ' ' Split "Lloyd Woolcock Donnell Baragwanath Williams Ashcroft Euler Ellery Gauss Ghosh Hilbert H... | Give a code snippet in #BQN
Soundex is an algorithm for creating indices for words based on their pronunciation.
Task
The goal is for homophones to be encoded to the same representation so that they can be matched despite minor differences in spelling (from the soundex Wikipedia article).
Caution
There is ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic | Bitmap/Bézier curves/Cubic | Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve
(definition on Wikipedia).
| #Fortran | Fortran | subroutine cubic_bezier(img, p1, p2, p3, p4, color)
type(rgbimage), intent(inout) :: img
type(point), intent(in) :: p1, p2, p3, p4
type(rgb), intent(in) :: color
integer :: i, j
real :: pts(0:N_SEG,0:1), t, a, b, c, d, x, y
do i = 0, N_SEG
t = real(i) / real(N_SEG)
a = (1.0 - t)**3.0
b = ... | Give a code snippet in #Fortran
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve
(definition on Wikipedia).
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Anonymous_recursion | Anonymous recursion | While implementing a recursive function, it often happens that we must resort to a separate helper function to handle the actual recursion.
This is usually the case when directly calling the current function would waste too many resources (stack space, execution time), causing unwanted side-effects, and/or the f... | #Delphi | Delphi |
program AnonymousRecursion;
{$APPTYPE CONSOLE}
uses
SysUtils;
function Fib(X: Integer): integer;
function DoFib(N: Integer): Integer;
begin
if N < 2 then Result:=N
else Result:=DoFib(N-1) + DoFib(N-2);
end;
begin
if X < 0 then raise Exception.Create('Argument < 0')
else Result:=DoFib(X);
end;
var... | Give a code snippet in #Delphi
While implementing a recursive function, it often happens that we must resort to a separate helper function to handle the actual recursion.
This is usually the case when directly calling the current function would waste too many resources (stack space, execution time), causing unwan... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Brace_expansion | Brace expansion | Brace expansion is a type of parameter expansion made popular by Unix shells, where it allows users to specify multiple similar string parameters without having to type them all out. E.g. the parameter enable_{audio,video} would be interpreted as if both enable_audio and enable_video had been specified.
Task[edit]
W... | #Racket | Racket | #lang racket/base
(require racket/match)
(define (merge-lists as . bss)
(match bss
['() as]
[(cons b bt)
(apply merge-lists
(for*/list ((a (in-list as)) (b (in-list b))) (append a b))
bt)]))
(define (get-item cs depth)
(let loop ((out '(())) (cs cs))
(match cs
['() (... | Give a code snippet in #Racket
Brace expansion is a type of parameter expansion made popular by Unix shells, where it allows users to specify multiple similar string parameters without having to type them all out. E.g. the parameter enable_{audio,video} would be interpreted as if both enable_audio and enable_video had... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Cocktail_sort_with_shifting_bounds | Sorting algorithms/Cocktail sort with shifting bounds |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Wren | Wren | import "/fmt" for Fmt
import "random" for Random
// translation of pseudo-code
var cocktailShakerSort = Fn.new { |a|
var begin = 0
var end = a.count - 2
while (begin <= end) {
var newBegin = end
var newEnd = begin
for (i in begin..end) {
if (a[i] > a[i+1]) {
... | Give a code snippet in #Wren
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Simple_windowed_application | Simple windowed application | Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| #Gambas | Gambas | iCount As Integer 'Counter of clicks!
hLabel As Label 'We need a Label
Public Sub Form_Open()
Dim hButton As Button 'We need a Button
With Me ... | Give a code snippet in #Gambas
Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Hash_from_two_arrays | Hash from two arrays | Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| #D.C3.A9j.C3.A0_Vu | Déjà Vu | local :h_keys [ :one :two :three ]
local :h_values [ 1 2 3 ]
local :h {}
for item in h_keys:
set-to h item pop-from h_values
| Give a code snippet in #D.C3.A9j.C3.A0_Vu
Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
Cop... | #REXX | REXX | /*REXX program determines if a string is numeric, using REXX's rules for numbers. */
yyy=' -123.78' /*or some such. */
/*strings below are all numeric (REXX).*/
zzz= ' -123.78 '
zzz= '-123.78'
zzz= '2'
zzz=... | Give a code snippet in #REXX
Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Ar... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Harshad_or_Niven_series | Harshad or Niven series | The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits.
For example, 42 is a Harshad number as 42 is divisible by (4 + 2) without remainder.
Assume that the series is defined as the numbers in increasing order.
Task
The task is to create a function/method/... | #Groovy | Groovy |
class HarshadNiven{ public static boolean find(int x)
{
int sum = 0,temp,var;
var = x;
while(x>0)
{
temp = x%10;
sum = sum + temp;
x = x/10;
}
if(var%sum==0) temp = 1;
else temp = 0;
return temp;
}
public static void main(String[] args)
... | Give a code snippet in #Groovy
The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits.
For example, 42 is a Harshad number as 42 is divisible by (4 + 2) without remainder.
Assume that the series is defined as the numbers in increasing order.
Task
The task... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Van_Eck_sequence | Van Eck sequence | The sequence is generated by following this pseudo-code:
A: The first term is zero.
Repeatedly apply:
If the last term is *new* to the sequence so far then:
B: The next term is zero.
Otherwise:
C: The next term is how far back this last term occured previously.
Example
Using ... | #8086_Assembly | 8086 Assembly | LIMIT: equ 1000
cpu 8086
org 100h
section .text
mov di,eck ; Zero out the memory
xor ax,ax
mov cx,LIMIT
rep stosw
mov bx,eck ; Base address
mov cx,LIMIT ; Limit
xor ax,ax
mov si,-1 ; Outer loop index
outer: inc si
dec cx
jcxz done
mov di,si ; Inner loop index
inner: dec di
js outer
shl si,1 ; Shif... | Give a code snippet in #8086_Assembly
The sequence is generated by following this pseudo-code:
A: The first term is zero.
Repeatedly apply:
If the last term is *new* to the sequence so far then:
B: The next term is zero.
Otherwise:
C: The next term is how far back this last term... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_the_missing_permutation | Find the missing permutation | ABCD
CABD
ACDB
DACB
BCDA
ACBD
ADCB
CDAB
DABC
BCAD
CADB
CDBA
... | #TI-83_BASIC | TI-83 BASIC | "ABCDCABDACDBDACBBCDAACBDADCBCDABDABCBCADCADBCDBACBADABDCADBCBDCADCBABACDBADCBDACCBDADBCADCAB"→Str0
"ABCD"→Str1
length(Str0)→L
[[0,0,0,0][0,0,0,0][0,0,0,0][0,0,0,0]]→[A]
For(I,1,L,4)
For(J,1,4,1)
sub(Str0,I+J-1,1)→Str2
For(K,1,4,1)
sub(Str1,K,1)→Str3
If Str2=Str3
Then
[A](J,K)+1→[A](J,K)
End
End
End
End
Matr►list([... | Give a code snippet in #TI-83_BASIC
ABCD
CABD
ACDB
DACB
BCDA
ACBD
ADCB
CDAB
DABC
BCAD
CADB
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Musical_scale | Musical scale | Task
Output the 8 notes of the C major diatonic scale to the default musical sound device on the system. Specifically, pitch must be tuned to 12-tone equal temperament (12TET) with the modern standard A=440Hz.
These are the notes "C, D, E, F, G, A, B, C(1 octave higher)", or "Do, Re, Mi, Fa, Sol, La, Si/Ti, Do(1 octa... | #REXX | REXX | /*REXX program sounds eight notes of the C major natural diatonic music scale.*/
parse arg ! /*obtain optional arguments from the CL*/
/* [↓] invoke boilerplate REXX code. */
if !all( arg() ) then exit ... | Give a code snippet in #REXX
Task
Output the 8 notes of the C major diatonic scale to the default musical sound device on the system. Specifically, pitch must be tuned to 12-tone equal temperament (12TET) with the modern standard A=440Hz.
These are the notes "C, D, E, F, G, A, B, C(1 octave higher)", or "Do, Re, Mi,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rock-paper-scissors | Rock-paper-scissors | Task
Implement the classic children's game Rock-paper-scissors, as well as a simple predictive AI (artificial intelligence) player.
Rock Paper Scissors is a two player game.
Each player chooses one of rock, paper or scissors, without knowing the other player's choice.
The winner is decided by a set of rules:
... | #UNIX_Shell | UNIX Shell | #!/bin/bash
choices=(rock paper scissors)
# comparison function, works like Perl
# winner x y = 2 if y beats x, 1 if x beats 1, 0 if it's a tie
winner() {
local left="$1" right="$2"
echo $(( (3 + left - right) % 3 ))
}
human_counts=(1 1 1)
human_count=3
computer_counts=(0 0 0)
games=0 human=0 computer=0
P... | Give a code snippet in #UNIX_Shell
Task
Implement the classic children's game Rock-paper-scissors, as well as a simple predictive AI (artificial intelligence) player.
Rock Paper Scissors is a two player game.
Each player chooses one of rock, paper or scissors, without knowing the other player's choice.
The w... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_comparison | String 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 |... | #11l | 11l | F compare(a, b)
I a < b {print(‘'#.' is strictly less than '#.'’.format(a, b))}
I a <= b {print(‘'#.' is less than or equal to '#.'’.format(a, b))}
I a > b {print(‘'#.' is strictly greater than '#.'’.format(a, b))}
I a >= b {print(‘'#.' is greater than or equal to '#.'’.format(a, b))}
I a == b {print... | Give a code snippet in #11l
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
Co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #Objective-C | Objective-C | #import <stdio.h>
#import <stdint.h>
#import <stdlib.h>
#import <string.h>
#import <Foundation/Foundation.h>
// this class exists to return a result between two
// vectors: if vectors have different "size", valid
// must be NO
@interface VResult : NSObject
{
@private
double value;
BOOL valid;
}
+(instancetype)ne... | Give a code snippet in #Objective-C
Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Variable_size/Get | Variable size/Get | Demonstrate how to get the size of a variable.
See also: Host introspection
| #C.23 | C# |
class Program
{
static void Main(string[] args)
{
int i = sizeof(int);
Console.WriteLine(i);
Console.ReadLine();
}
}
| Give a code snippet in #C.23
Demonstrate how to get the size of a variable.
See also: Host introspection
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Jacobsthal_numbers | Jacobsthal numbers | Jacobsthal numbers are an integer sequence related to Fibonacci numbers. Similar to Fibonacci, where each term is the sum of the previous two terms, each term is the sum of the previous, plus twice the one before that. Traditionally the sequence starts with the given terms 0, 1.
J0 = 0
J1 = 1
Jn = Jn-1 + 2 ×... | #Raku | Raku | my $jacobsthal = cache lazy 0, 1, * × 2 + * … *;
my $jacobsthal-lucas = lazy 2, 1, * × 2 + * … *;
say "First 30 Jacobsthal numbers:";
say $jacobsthal[^30].batch(5)».fmt("%9d").join: "\n";
say "\nFirst 30 Jacobsthal-Lucas numbers:";
say $jacobsthal-lucas[^30].batch(5)».fmt("%9d").join: "\n";
say "\nFirst 20 Jacobs... | Give a code snippet in #Raku
Jacobsthal numbers are an integer sequence related to Fibonacci numbers. Similar to Fibonacci, where each term is the sum of the previous two terms, each term is the sum of the previous, plus twice the one before that. Traditionally the sequence starts with the given terms 0, 1.
J0 = ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #68000_Assembly | 68000 Assembly | MyVar:
DC.L 0 ;reserves 4 bytes of storage. The label MyVar represents the address of the four 0 bytes shown here.
MyOtherVar:
DC.L $C0 ;reserves 8 bytes of storage. The first four bytes are initialized to 00 00 00 C0 and the second four to $00 $00 $01 $F4.
DC.L 500 ;MyOtherVar points to the first four bytes... | Give a code snippet in #68000_Assembly
Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| christopher/rosetta-code |
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