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/Unbias_a_random_generator | Unbias a random generator |
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to create a function/method/sub... | #zkl | zkl | fcn randN(N){ (not (0).random(N)).toInt() }
fcn unbiased(randN){ while((a:=randN())==randN()){} a } | Give a code snippet in #zkl
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Levenshtein_distance/Alignment | Levenshtein distance/Alignment | The Levenshtein distance algorithm returns the number of atomic operations (insertion, deletion or edition) that must be performed on a string in order to obtain an other one, but it does not say anything about the actual operations used or their order.
An alignment is a notation used to describe the operations used t... | #Rust | Rust | [dependencies]
edit-distance = "^1.0.0" | Give a code snippet in #Rust
The Levenshtein distance algorithm returns the number of atomic operations (insertion, deletion or edition) that must be performed on a string in order to obtain an other one, but it does not say anything about the actual operations used or their order.
An alignment is a notation used to ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Undefined_values | Undefined values | #Go | Go | package main
import "fmt"
var (
s []int
p *int
f func()
i interface{}
m map[int]int
c chan int
)
func main() {
fmt.Println("Exercise nil objects:")
status()
// initialize objects
s = make([]int, 1)
p = &s[0] // yes, reference element of slice just created
f = func... | Give a code snippet in #Go
| 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
... | #PowerShell | PowerShell |
function pop-count($n) {
(([Convert]::ToString($n, 2)).toCharArray() | where {$_ -eq '1'}).count
}
"pop_count 3^n: $(1..29 | foreach -Begin {$n = 1; (pop-count $n)} -Process {$n = 3*$n; (pop-count $n)} )"
"even pop_count: $($m = $n = 0; while($m -lt 30) {if(0 -eq ((pop-count $n)%2)) {$m += 1; $n}; $n += 1} )"
"o... | Give a code snippet in #PowerShell
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/AKS_test_for_primes | AKS test for primes | The AKS algorithm for testing whether a number is prime is a polynomial-time algorithm based on an elementary theorem about Pascal triangles.
The theorem on which the test is based can be stated as follows:
a number
p
{\displaystyle p}
is prime if and only if all the coefficients of the polynomial ... | #Python | Python | def expand_x_1(n):
# This version uses a generator and thus less computations
c =1
for i in range(n//2+1):
c = c*(n-i)//(i+1)
yield c
def aks(p):
if p==2:
return True
for i in expand_x_1(p):
if i % p:
# we stop without computing all possible solutions
ret... | Give a code snippet in #Python
The AKS algorithm for testing whether a number is prime is a polynomial-time algorithm based on an elementary theorem about Pascal triangles.
The theorem on which the test is based can be stated as follows:
a number
p
{\displaystyle p}
is prime if and only if all the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Maze_solving | Maze solving | Task
For a maze generated by this task, write a function
that finds (and displays) the shortest path between two cells.
Note that because these mazes are generated by the Depth-first search algorithm, they contain no circular paths,
and a simple depth-first tree search can be used.
| #EGL | EGL | program MazeGenAndSolve
// First and last columns/rows are "dead" cells. Makes generating
// a maze with border walls much easier. Therefore, a visible
// 20x20 maze has a maze size of 22.
mazeSize int = 22;
south boolean[][];
west boolean[][];
visited boolean[][];
// Solution va... | Give a code snippet in #EGL
Task
For a maze generated by this task, write a function
that finds (and displays) the shortest path between two cells.
Note that because these mazes are generated by the Depth-first search algorithm, they contain no circular paths,
and a simple depth-first tree search can be used.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Handle_a_signal | Handle a signal | Most operating systems provide interrupt facilities, sometimes called signals either generated by the user or as a result of program failure or reaching a limit like file space.
Unhandled signals generally terminate a program in a disorderly manner.
Signal handlers are created so that the program behaves in a well-defi... | #FreeBASIC | FreeBASIC | Dim Shared As Double start
start = Timer
Dim As Integer n = 1
Dim As String s
Do
Print n
s = Inkey
If s = Chr(255) + "k" Then
Dim As Double elapsed = Timer- start + n * 0.5
Print Using "Program has run for & seconds."; elapsed
End
Else
Sleep 500, 1
n += 1
E... | Give a code snippet in #FreeBASIC
Most operating systems provide interrupt facilities, sometimes called signals either generated by the user or as a result of program failure or reaching a limit like file space.
Unhandled signals generally terminate a program in a disorderly manner.
Signal handlers are created so that... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Date_format | Date format | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Task
Display the current date in the formats of:
2007-11-23 and
Friday, November 23, 2007
| #Raven | Raven | time int as today | Give a code snippet in #Raven
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Task
Display the current date in the formats of:
2007-11-23 and
Friday, November 23, 2007
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_control_codes_and_extended_characters_from_a_string | Strip control codes and extended characters from a string | Task
Strip control codes and extended characters from a string.
The solution should demonstrate how to achieve each of the following results:
a string with control codes stripped (but extended characters not stripped)
a string with control codes and extended characters stripped
In ASCII, the control codes ... | #F.23 | F# |
open System
let stripControl (arg:string) =
String(Array.filter (fun x -> not (Char.IsControl(x))) (arg.ToCharArray()))
//end stripControl
let stripExtended (arg:string) =
let numArr = Array.map (fun (x:char) -> Convert.ToUInt16(x)) (arg.ToCharArray()) in
String([|for num in numArr do if num >= 32us... | Give a code snippet in #F.23
Task
Strip control codes and extended characters from a string.
The solution should demonstrate how to achieve each of the following results:
a string with control codes stripped (but extended characters not stripped)
a string with control codes and extended characters stripped
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Higher-order_functions | Higher-order functions | Task
Pass a function as an argument to another function.
Related task
First-class functions
| #REBOL | REBOL | rebol [
Title: "Function Argument"
URL: http://rosettacode.org/wiki/Function_as_an_Argument
]
map: func [
"Apply function to contents of list, return new list."
f [function!] "Function to apply to list."
data [block! list!] "List to transform."
/local result i
][
result: copy [] repeat i data [append result f... | Give a code snippet in #REBOL
Task
Pass a function as an argument to another function.
Related task
First-class functions
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_an_HTML_table | Create an HTML table | Create an HTML table.
The table body should have at least three rows of three columns.
Each of these three columns should be labelled "X", "Y", and "Z".
An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is filled with sequential row numbers.
The... | #Euphoria | Euphoria | puts(1,"<table>\n")
puts(1," <tr><th></th><th>X</th><th>Y</th><th>Z</th></tr>\n")
for i = 1 to 3 do
printf(1," <tr><td>%d</td>",i)
for j = 1 to 3 do
printf(1,"<td>%d</td>",rand(10000))
end for
puts(1,"</tr>\n")
end for
puts(1,"</table>") | Give a code snippet in #Euphoria
Create an HTML table.
The table body should have at least three rows of three columns.
Each of these three columns should be labelled "X", "Y", and "Z".
An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is filled ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Combinations_with_repetitions | Combinations with repetitions | The set of combinations with repetitions is computed from a set,
S
{\displaystyle S}
(of cardinality
n
{\displaystyle n}
), and a size of resulting selection,
k
{\displaystyle k}
, by reporting the sets of cardinality
k
{\displaystyle k}
where each member of those sets is chosen from
S... | #Prolog | Prolog |
combinations_of_length(_,[]).
combinations_of_length([X|T],[X|Combinations]):-
combinations_of_length([X|T],Combinations).
combinations_of_length([_|T],[X|Combinations]):-
combinations_of_length(T,[X|Combinations]).
| Give a code snippet in #Prolog
The set of combinations with repetitions is computed from a set,
S
{\displaystyle S}
(of cardinality
n
{\displaystyle n}
), and a size of resulting selection,
k
{\displaystyle k}
, by reporting the sets of cardinality
k
{\displaystyle k}
where each member of... | 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... | #R | R |
int2str <- function(x, b) {
if(x==0) return("0")
if(x<0) return(paste0("-", base(-x,b)))
map <- c(as.character(0:9), letters)
res <- ""
while (x>0) {
res <- c(map[x %% b + 1], res)
x <- x %/% b
}
return(paste(res, collapse=""))
}
str2int <- function(s, b) {
map <- c(as.character(0:9), ... | Give a code snippet in #R
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, bu... | 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
... | #AutoHotkey | AutoHotkey | A(m, n) {
If (m > 0) && (n = 0)
Return A(m-1,1)
Else If (m > 0) && (n > 0)
Return A(m-1,A(m, n-1))
Else If (m=0)
Return n+1
}
; Example:
MsgBox, % "A(1,2) = " A(1,2) | Give a code snippet in #AutoHotkey
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/Zero_to_the_zero_power | Zero to the zero power | Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0**0 or 0^0 at compile time, ... | #Locomotive_Basic | Locomotive Basic | print 0🠅0 | Give a code snippet in #Locomotive_Basic
Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0*... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher/Cryptanalysis | Vigenère cipher/Cryptanalysis | Given some text you suspect has been encrypted with a Vigenère cipher, extract the key and plaintext. There are several methods for doing this. See the Wikipedia entry for more information. Use the following encrypted text:
MOMUD EKAPV TQEFM OEVHP AJMII CDCTI FGYAG JSPXY ALUYM NSMYH
VUXJE LEPXJ FXGCM JHKDZ RYICU HYPUS... | #Perl | Perl | use strict;
use warnings;
use feature 'say';
# from Wikipedia
my %English_letter_freq = (
E => 12.70, L => 4.03, Y => 1.97, P => 1.93, T => 9.06, A => 8.17, O => 7.51, I => 6.97, N => 6.75,
S => 6.33, H => 6.09, R => 5.99, D => 4.25, C => 2.78, U => 2.76, M => 2.41, W => 2.36, F => 2.23,
... | Give a code snippet in #Perl
Given some text you suspect has been encrypted with a Vigenère cipher, extract the key and plaintext. There are several methods for doing this. See the Wikipedia entry for more information. Use the following encrypted text:
MOMUD EKAPV TQEFM OEVHP AJMII CDCTI FGYAG JSPXY ALUYM NSMYH
VUXJE... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_append | String append |
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 |... | #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Var s = "String"
s += " append"
Print s
Sleep | Give a code snippet in #FreeBASIC
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 Operati... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file | Read a specific line from a file | Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in a variable or in memory (fo... | #Ursa | Ursa | decl string<> lines
decl file f
f.open "filename.txt"
set lines (f.readlines)
f.close
if (< (size lines) 7)
out "the file has less than seven lines" endl console
stop
end if
out "the seventh line in the file is:" endl endl console
out lines<6> endl console | Give a code snippet in #Ursa
Some languages have special semantics for obtaining a known line number from a file.
Task
Demonstrate how to obtain the contents of a specific line within a file.
For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained, and store it in... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Palindrome_detection | Palindrome detection | A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibly as a wrapper to the first) which ... | #HicEst | HicEst | result = Palindrome( "In girum imus nocte et consumimur igni" ) ! returns 1
END
FUNCTION Palindrome(string)
CHARACTER string, CopyOfString
L = LEN(string)
ALLOCATE(CopyOfString, L)
CopyOfString = string
EDIT(Text=CopyOfString, UpperCase=L)
L = L - EDIT(Text=CopyOfString, End, Left=' ', Delete, ... | Give a code snippet in #HicEst
A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibly a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/24_game | 24 game | The 24 Game tests one's mental arithmetic.
Task
Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed.
The program should prompt for the player to enter an arithmetic expression using just those, and all of those four digits, used exactly once each. T... | #Factor | Factor | USING:
combinators.short-circuit
continuations
eval
formatting
fry
kernel
io
math math.ranges
prettyprint
random
sequences
sets ;
IN: 24game
: choose4 ( -- seq )
4 [ 9 [1,b] random ] replicate ;
: step ( numbers -- ? )
readln
[
parse-string
... | Give a code snippet in #Factor
The 24 Game tests one's mental arithmetic.
Task
Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed.
The program should prompt for the player to enter an arithmetic expression using just those, and all of those four d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_block_comments | Strip block comments | A block comment begins with a beginning delimiter and ends with a ending delimiter, including the delimiters. These delimiters are often multi-character sequences.
Task
Strip block comments from program text (of a programming language much like classic C).
Your demos should at least handle simple, non-ne... | #Racket | Racket |
#lang at-exp racket
;; default delimiters (strings -- not regexps)
(define comment-start-str "/*")
(define comment-end-str "*/")
(define (strip-comments text [rx1 comment-start-str] [rx2 comment-end-str])
(regexp-replace* (~a (regexp-quote rx1) ".*?" (regexp-quote rx2))
text ""))
((compose1... | Give a code snippet in #Racket
A block comment begins with a beginning delimiter and ends with a ending delimiter, including the delimiters. These delimiters are often multi-character sequences.
Task
Strip block comments from program text (of a programming language much like classic C).
Your demos shoul... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fractal_tree | Fractal tree | Generate and draw a fractal tree.
Draw the trunk
At the end of the trunk, split by some angle and draw two branches
Repeat at the end of each branch until a sufficient level of branching is reached
Related tasks
Pythagoras Tree
| #PHP | PHP |
<?php
header("Content-type: image/png");
$width = 512;
$height = 512;
$img = imagecreatetruecolor($width,$height);
$bg = imagecolorallocate($img,255,255,255);
imagefilledrectangle($img, 0, 0, $width, $width, $bg);
$depth = 8;
function drawTree($x1, $y1, $angle, $depth){
global $img;
if ($depth != 0){
... | Give a code snippet in #PHP
Generate and draw a fractal tree.
Draw the trunk
At the end of the trunk, split by some angle and draw two branches
Repeat at the end of each branch until a sufficient level of branching is reached
Related tasks
Pythagoras Tree
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Yin_and_yang | Yin and yang | One well-known symbol of the philosophy of duality known as yin and yang is the taijitu.
Task
Create a function that, given a parameter representing size, generates such a symbol scaled to the requested size.
Generate and display the symbol for two different (small) sizes.
| #J | J | yinyang=:3 :0
radii=. y*1 3 6
ranges=. i:each radii
squares=. ,"0/~each ranges
circles=. radii ([ >: +/"1&.:*:@])each squares
cInds=. ({:radii) +each circles #&(,/)each squares
M=. ' *.' {~ circles (* 1 + 0 >: {:"1)&(_1&{::) squares
offset=. 3*y,0
M=. '*' ((_2 {:: cInds) <@:+"1 offset)} M
M=. '.' ... | Give a code snippet in #J
One well-known symbol of the philosophy of duality known as yin and yang is the taijitu.
Task
Create a function that, given a parameter representing size, generates such a symbol scaled to the requested size.
Generate and display the symbol for two different (small) sizes.
| 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... | #Fantom | Fantom |
class Rename
{
public static Void main ()
{
// rename file/dir in current directory
File.rename("input.txt".toUri).rename("output.txt")
File.rename("docs/".toUri).rename("mydocs/")
// rename file/dir in root directory
File.rename("/input.txt".toUri).rename("/output.txt")
File.rename("/docs... | Give a code snippet in #Fantom
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 r... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Checkpoint_synchronization | Checkpoint synchronization | The checkpoint synchronization is a problem of synchronizing multiple tasks. Consider a workshop where several workers (tasks) assembly details of some mechanism. When each of them completes his work they put the details together. There is no store, so a worker who finished its part first must wait for others before st... | #Rust | Rust |
//! We implement this task using Rust's Barriers. Barriers are simply thread synchronization
//! points--if a task waits at a barrier, it will not continue until the number of tasks for which
//! the variable was initialized are also waiting at the barrier, at which point all of them will
//! stop waiting. This can... | Give a code snippet in #Rust
The checkpoint synchronization is a problem of synchronizing multiple tasks. Consider a workshop where several workers (tasks) assembly details of some mechanism. When each of them completes his work they put the details together. There is no store, so a worker who finished its part first ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/HTTP | HTTP | Task
Access and print a URL's content (the located resource) to the console.
There is a separate task for HTTPS Requests.
| #Wren | Wren | /* http.wren */
var CURLOPT_URL = 10002
var CURLOPT_FOLLOWLOCATION = 52
var CURLOPT_ERRORBUFFER = 10010
foreign class Curl {
construct easyInit() {}
foreign easySetOpt(opt, param)
foreign easyPerform()
foreign easyCleanup()
}
var curl = Curl.easyInit()
if (curl == 0) {
System.print("Erro... | Give a code snippet in #Wren
Task
Access and print a URL's content (the located resource) to the console.
There is a separate task for HTTPS Requests.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Fermat_numbers | Fermat numbers | In mathematics, a Fermat number, named after Pierre de Fermat who first studied them, is a positive integer of the form Fn = 22n + 1 where n is a non-negative integer.
Despite the simplicity of generating Fermat numbers, they have some powerful mathematical properties and are extensively used in cryptography & pseudo-... | #PicoLisp | PicoLisp | (seed (in "/dev/urandom" (rd 8)))
(de **Mod (X Y N)
(let M 1
(loop
(when (bit? 1 Y)
(setq M (% (* M X) N)) )
(T (=0 (setq Y (>> 1 Y)))
M )
(setq X (% (* X X) N)) ) ) )
(de isprime (N)
(cache '(NIL) N
(if (== N 2)
T
(and
(... | Give a code snippet in #PicoLisp
In mathematics, a Fermat number, named after Pierre de Fermat who first studied them, is a positive integer of the form Fn = 22n + 1 where n is a non-negative integer.
Despite the simplicity of generating Fermat numbers, they have some powerful mathematical properties and are extensiv... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_and_product_of_an_array | Sum and product of an array | Task
Compute the sum and product of an array of integers.
| #Tcl | Tcl | set arr [list 3 6 8]
set sum [expr [join $arr +]]
set prod [expr [join $arr *]] | Give a code snippet in #Tcl
Task
Compute the sum and product of an array of integers.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_comments_from_a_string | Strip comments from a string | Strip comments from a string
You are encouraged to solve this task according to the task description, using any language you may know.
The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line.
Whitespace debacle: There is s... | #AWK | AWK | #!/usr/local/bin/awk -f
{
sub("[ \t]*[#;].*$","",$0);
print;
} | Give a code snippet in #AWK
Strip comments from a string
You are encouraged to solve this task according to the task description, using any language you may know.
The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line.
Whi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Haversine_formula | Haversine formula |
This page uses content from Wikipedia. The original article was at Haversine formula. 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)
The haversine formula is an equation important in navigation, g... | #Ada | Ada | with Ada.Text_IO; use Ada.Text_IO;
with Ada.Long_Float_Text_IO; use Ada.Long_Float_Text_IO;
with Ada.Numerics.Generic_Elementary_Functions;
procedure Haversine_Formula is
package Math is new Ada.Numerics.Generic_Elementary_Functions (Long_Float); use Math;
-- Compute great circle distance, given latitude an... | Give a code snippet in #Ada
This page uses content from Wikipedia. The original article was at Haversine formula. 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)
The haversine formula is an equati... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ... | #SNUSP | SNUSP | @!\+++++++++# /<<+>+>-\
fib\==>>+<<?!/>!\ ?/\
#<</?\!>/@>\?-<<</@>/@>/>+<-\
\-/ \ !\ !\ !\ ?/# | Give a code snippet in #SNUSP
The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Magic_squares_of_singly_even_order | Magic squares of singly even order | A magic square is an NxN square matrix whose numbers consist of consecutive numbers arranged so that the sum of each row and column, and both diagonals are equal to the same sum (which is called the magic number or magic constant).
A magic square of singly even order has a size that is a multiple of 4, plus 2 (e.g. 6,... | #Julia | Julia | function oddmagicsquare(order)
if iseven(order)
order += 1
end
q = zeros(Int, (order, order))
p = 1
i = div(order, 2) + 1
j = 1
while p <= order * order
q[i, j] = p
ti = (i + 1 > order) ? 1 : i + 1
tj = (j - 1 < 1) ? order : j - 1
if q[ti, tj] != 0
... | Give a code snippet in #Julia
A magic square is an NxN square matrix whose numbers consist of consecutive numbers arranged so that the sum of each row and column, and both diagonals are equal to the same sum (which is called the magic number or magic constant).
A magic square of singly even order has a size that is a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/State_name_puzzle | State name puzzle | Background
This task is inspired by Mark Nelson's DDJ Column "Wordplay" and one of the weekly puzzle challenges from Will Shortz on NPR Weekend Edition [1] and originally attributed to David Edelheit.
The challenge was to take the names of two U.S. States, mix them all together, then rearrange the letters to form the... | #Go | Go | package main
import (
"fmt"
"unicode"
)
var states = []string{"Alabama", "Alaska", "Arizona", "Arkansas",
"California", "Colorado", "Connecticut",
"Delaware",
"Florida", "Georgia", "Hawaii",
"Idaho", "Illinois", "Indiana", "Iowa",
"Kansas", "Kentucky", "Louisiana",
"Maine", "Maryland... | Give a code snippet in #Go
Background
This task is inspired by Mark Nelson's DDJ Column "Wordplay" and one of the weekly puzzle challenges from Will Shortz on NPR Weekend Edition [1] and originally attributed to David Edelheit.
The challenge was to take the names of two U.S. States, mix them all together, then rearr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nim_game | Nim game | Nim game
You are encouraged to solve this task according to the task description, using any language you may know.
Nim is a simple game where the second player ─── if they know the trick ─── will always win.
The game has only 3 rules:
start with 12 tokens
each player takes 1, 2, or 3 tokens in tur... | #Haskell | Haskell | import Data.Char (isDigit, digitToInt)
import System.IO
prompt :: String
prompt = "How many do you take? 1, 2 or 3? "
getPlayerSelection :: IO Int
getPlayerSelection = do
hSetBuffering stdin NoBuffering
c <- getChar
putChar '\n'
if isDigit c && digitToInt c <= 3 then
pure (digitToInt c)
else do
... | Give a code snippet in #Haskell
Nim game
You are encouraged to solve this task according to the task description, using any language you may know.
Nim is a simple game where the second player ─── if they know the trick ─── will always win.
The game has only 3 rules:
start with 12 tokens
each player take... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Prime_decomposition | Prime decomposition | The prime decomposition of a number is defined as a list of prime numbers
which when all multiplied together, are equal to that number.
Example
12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3}
Task
Write a function which returns an array or collection which contains the prime decomposition of a given ... | #Quackery | Quackery | [ [] swap
dup times
[ [ dup i^ 2 + /mod
0 = while
nip dip
[ i^ 2 + join ]
again ]
drop
dup 1 = if conclude ]
drop ] is primefactors ( n --> [ )
1047552 primefactors echo | Give a code snippet in #Quackery
The prime decomposition of a number is defined as a list of prime numbers
which when all multiplied together, are equal to that number.
Example
12 = 2 × 2 × 3, so its prime decomposition is {2, 2, 3}
Task
Write a function which returns an array or collection which contains t... | christopher/rosetta-code | |
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... | #Elena | Elena | import extensions;
public program()
{
var i := 0u;
while (true)
{
console.printLine(i);
i += 1u
}
} | Give a code snippet in #Elena
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 li... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_occurrences_of_a_substring | Count occurrences of a substring | Task
Create a function, or show a built-in function, to count the number of non-overlapping occurrences of a substring inside a string.
The function should take two arguments:
the first argument being the string to search, and
the second a substring to be searched for.
It should return an integer cou... | #360_Assembly | 360 Assembly | * Count occurrences of a substring 05/07/2016
COUNTSTR CSECT
USING COUNTSTR,R13 base register
B 72(R15) skip savearea
DC 17F'0' savearea
STM R14,R12,12(R13) prolog
ST R13,4(R15) "
ST R15,8(R13) ... | Give a code snippet in #360_Assembly
Task
Create a function, or show a built-in function, to count the number of non-overlapping occurrences of a substring inside a string.
The function should take two arguments:
the first argument being the string to search, and
the second a substring to be searched f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Vampire_number | Vampire number | A vampire number is a natural decimal number with an even number of digits, that can be factored into two integers.
These two factors are called the fangs, and must have the following properties:
they each contain half the number of the decimal digits of the original number
together they consist of exactl... | #AutoHotkey | AutoHotkey | SetBatchLines -1 ; used to improve performance
; (you can make it much faster by removing the informative tooltips)
;********************
; CONFIG
;********************
StartingNumber := 10
NumberLimit := 126030
CounterLimit := 25 ; calculations stop when one of these limits is reached
AdditionalNumbers := "167582432... | Give a code snippet in #AutoHotkey
A vampire number is a natural decimal number with an even number of digits, that can be factored into two integers.
These two factors are called the fangs, and must have the following properties:
they each contain half the number of the decimal digits of the original numbe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Mode | Averages/Mode | Task[edit]
Write a program to find the mode value of a collection.
The case where the collection is empty may be ignored. Care must be taken to handle the case where the mode is non-unique.
If it is not appropriate or possible to support a general collection, use a vector (array), if possible. If it is not appropriat... | #ERRE | ERRE | PROGRAM MODE_AVG
!$INTEGER
DIM A[10],B[10],Z[10]
PROCEDURE SORT(Z[],P->Z[])
LOCAL N,FLIPS
FLIPS=TRUE
WHILE FLIPS DO
FLIPS=FALSE
FOR N=0 TO P-1 DO
IF Z[N]>Z[N+1] THEN SWAP(Z[N],Z[N+1]) FLIPS=TRUE
END FOR
END WHILE
END PROCEDURE
PROCEDURE CALC_MODE(Z[],P->MODES$)
LOCAL I,O... | Give a code snippet in #ERRE
Task[edit]
Write a program to find the mode value of a collection.
The case where the collection is empty may be ignored. Care must be taken to handle the case where the mode is non-unique.
If it is not appropriate or possible to support a general collection, use a vector (array), if pos... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Boolean_values | Boolean values | Task
Show how to represent the boolean states "true" and "false" in a language.
If other objects represent "true" or "false" in conditionals, note it.
Related tasks
Logical operations
| #i | i | main
//Bits aka Booleans.
b $= bit()
b $= true
print(b)
b $= false
print(b)
//Non-zero values are true.
b $= bit(1)
print(b)
b $= -1
print(b)
//Zero values are false
b $= 0
print(b)
} | Give a code snippet in #i
Task
Show how to represent the boolean states "true" and "false" in a language.
If other objects represent "true" or "false" in conditionals, note it.
Related tasks
Logical operations
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_and_product_of_an_array | Sum and product of an array | Task
Compute the sum and product of an array of integers.
| #OCaml | OCaml | (* ints *)
let a = [| 1; 2; 3; 4; 5 |];;
Array.fold_left (+) 0 a;;
Array.fold_left ( * ) 1 a;;
(* floats *)
let a = [| 1.0; 2.0; 3.0; 4.0; 5.0 |];;
Array.fold_left (+.) 0.0 a;;
Array.fold_left ( *.) 1.0 a;; | Give a code snippet in #OCaml
Task
Compute the sum and product of an array of integers.
| 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... | #jq | jq | recurse("SPAM") | Give a code snippet in #jq
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/I... | 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... | #AppleScript | AppleScript | -- LAST FRIDAYS OF YEAR ------------------------------------------------------
-- lastFridaysOfYear :: Int -> [Date]
on lastFridaysOfYear(y)
-- lastWeekDaysOfYear :: Int -> Int -> [Date]
script lastWeekDaysOfYear
on |λ|(intYear, iWeekday)
-- lastWeekDay :: Int -> Int -> Date
... | Give a code snippet in #AppleScript
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
2012-02-2... | 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
... | #Nanoquery | Nanoquery | def sorted(list)
if len(list) = 0
return true
end
for i in range(0, len(list) - 2)
if list[i] > list[i + 1]
return false
end
end
return true
end
def bogosort(list)
while not sorted(list)
... | Give a code snippet in #Nanoquery
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 |
Quic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Palindrome_detection | Palindrome detection | A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibly as a wrapper to the first) which ... | #8086_Assembly | 8086 Assembly | cpu 8086
org 100h
section .text
jmp demo
;;; Check if the $-terminated string in [DS:SI] is a palindrome.
;;; Returns with zero flag set if so.
;;; Destroyed: AL, CX, SI, DI, ES.
palin: push es ; Set ES=DS.
pop ds
mov al,'$' ; Find end of string
mov cx,-1
mov di,si
repne scasb
dec di ; Move back to last... | Give a code snippet in #8086_Assembly
A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (pos... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Word_wheel | Word wheel | A "word wheel" is a type of word game commonly found on the "puzzle" page of
newspapers. You are presented with nine letters arranged in a circle or 3×3
grid. The objective is to find as many words as you can using only the letters
contained in the wheel or grid. Each word must contain the letter in the centre
of the w... | #Picat | Picat | main =>
MinLen = 3,
MaxLen = 9,
Chars = "ndeokgelw",
MustContain = 'k',
WordList = "unixdict.txt",
Words = read_file_lines(WordList),
Res = word_wheel(Chars,Words,MustContain,MinLen, MaxLen),
println(Res),
println(len=Res.len),
nl.
word_wheel(Chars,Words,MustContain,MinLen,MaxLen) = Res.reverse ... | Give a code snippet in #Picat
A "word wheel" is a type of word game commonly found on the "puzzle" page of
newspapers. You are presented with nine letters arranged in a circle or 3×3
grid. The objective is to find as many words as you can using only the letters
contained in the wheel or grid. Each word must contain th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gray_code | Gray code | Gray code
Karnaugh maps
Create functions to encode a number to and decode a number from Gray code.
Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary).
There are many possible Gray codes. The follow... | #Component_Pascal | Component Pascal |
MODULE GrayCodes;
IMPORT StdLog,SYSTEM;
PROCEDURE Encode*(i: INTEGER; OUT x: INTEGER);
VAR
j: INTEGER;
s,r: SET;
BEGIN
s := BITS(i);j := MAX(SET);
WHILE (j >= 0) & ~(j IN s) DO DEC(j) END;
r := {};IF j >= 0 THEN INCL(r,j) END;
WHILE j > 0 DO
IF ((j IN s) & ~(j - 1 IN s)) OR (~(j IN s) & (j - 1 IN s)) THEN ... | Give a code snippet in #Component_Pascal
Gray code
Karnaugh maps
Create functions to encode a number to and decode a number from Gray code.
Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary).
Ther... | christopher/rosetta-code | |
http://rosettacode.org/wiki/System_time | System time | Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
Date format
See also
Retr... | #Fortran | Fortran | integer :: start, stop, rate
real :: result
! optional 1st integer argument (COUNT) is current raw system clock counter value (not UNIX epoch millis!!)
! optional 2nd integer argument (COUNT_RATE) is clock cycles per second
! optional 3rd integer argument (COUNT_MAX) is maximum clock counter value
call system_clock( ... | Give a code snippet in #Fortran
Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Draw_a_cuboid | Draw a cuboid | Task
Draw a cuboid with relative dimensions of 2 × 3 × 4.
The cuboid can be represented graphically, or in ASCII art, depending on the language capabilities.
To fulfill the criteria of being a cuboid, three faces must be visible.
Either static or rotational projection is acceptable for this task.
R... | #Frink | Frink | res = 254 / in
s = 1/2 inch res
v = callJava["frink.graphics.VoxelArray", "cube", [-s, s, -s, s, -s, s, true]]
v.projectX[undef].show["X"]
v.projectY[undef].show["Y"]
v.projectZ[undef].show["Z"]
filename = "cube.stl"
print["Writing $filename..."]
w = new Writer[filename]
w.println[v.toSTLFormat["cube", 1/(res mm... | Give a code snippet in #Frink
Task
Draw a cuboid with relative dimensions of 2 × 3 × 4.
The cuboid can be represented graphically, or in ASCII art, depending on the language capabilities.
To fulfill the criteria of being a cuboid, three faces must be visible.
Either static or rotational projection is... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Yellowstone_sequence | Yellowstone sequence | The Yellowstone sequence, also called the Yellowstone permutation, is defined as:
For n <= 3,
a(n) = n
For n >= 4,
a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and
is not relatively prime to a(n-2).
The sequence is a permutation of the natural n... | #Forth | Forth | : array create cells allot ;
: th cells + ; \ some helper words
30 constant #yellow \ number of yellowstones
#yellow array y \ create array
( n1 n2 -- n3)
: gcd dup if tuck mod recurse exit then drop ;
: init 3 ... | Give a code snippet in #Forth
The Yellowstone sequence, also called the Yellowstone permutation, is defined as:
For n <= 3,
a(n) = n
For n >= 4,
a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and
is not relatively prime to a(n-2).
The sequence is... | christopher/rosetta-code | |
http://rosettacode.org/wiki/HTTPS/Client-authenticated | HTTPS/Client-authenticated | Demonstrate how to connect to a web server over HTTPS where that server requires that the client present a certificate to prove who (s)he is. Unlike with the HTTPS request with authentication task, it is not acceptable to perform the authentication by a username/password or a set cookie.
This task is in general useful... | #Tcl | Tcl | package require http
package require tls
set cert myCert.p12
http::register https 443 [list \
::tls::socket -certfile $cert -password getPass]
proc getPass {} {
return "myPassword"; # Just a noddy example...
}
# Make a secure authenticated connection
set token [http::geturl https://verysecure.example.com/... | Give a code snippet in #Tcl
Demonstrate how to connect to a web server over HTTPS where that server requires that the client present a certificate to prove who (s)he is. Unlike with the HTTPS request with authentication task, it is not acceptable to perform the authentication by a username/password or a set cookie.
T... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Abundant,_deficient_and_perfect_number_classifications | Abundant, deficient and perfect number classifications | These define three classifications of positive integers based on their proper divisors.
Let P(n) be the sum of the proper divisors of n where the proper divisors are all positive divisors of n other than n itself.
if P(n) < n then n is classed as deficient (OEIS A005100).
if P(n)... | #Julia | Julia |
function pcontrib(p::Int64, a::Int64)
n = one(p)
pcon = one(p)
for i in 1:a
n *= p
pcon += n
end
return pcon
end
function divisorsum(n::Int64)
dsum = one(n)
for (p, a) in factor(n)
dsum *= pcontrib(p, a)
end
dsum -= n
end
| Give a code snippet in #Julia
These define three classifications of positive integers based on their proper divisors.
Let P(n) be the sum of the proper divisors of n where the proper divisors are all positive divisors of n other than n itself.
if P(n) < n then n is classed as deficient... | christopher/rosetta-code | |
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... | #PL.2FM | PL/M | 100H:
/* CP/M CALL AND NUMBER OUTPUT ROUTINE */
BDOS: PROCEDURE (FN, ARG);
DECLARE FN BYTE, ARG ADDRESS;
GO TO 5;
END BDOS;
PRINT: PROCEDURE (STR);
DECLARE STR ADDRESS;
CALL BDOS(9, STR);
END PRINT;
PRINT$NUMBER: PROCEDURE (N);
DECLARE S (8) BYTE INITIAL ('.....',13,10,'$');
DECLARE (N, P)... | Give a code snippet in #PL.2FM
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 l... | christopher/rosetta-code | |
http://rosettacode.org/wiki/History_variables | History variables | Storing the history of objects in a program is a common task.
Maintaining the history of an object in a program has traditionally required programmers either to write specific code for handling the historical data, or to use a library which supports history logging.
History variables are variables in a programming la... | #Swift | Swift | var historyOfHistory = [Int]()
var history:Int = 0 {
willSet {
historyOfHistory.append(history)
}
}
history = 2
history = 3
history = 4
println(historyOfHistory)
| Give a code snippet in #Swift
Storing the history of objects in a program is a common task.
Maintaining the history of an object in a program has traditionally required programmers either to write specific code for handling the historical data, or to use a library which supports history logging.
History variables ar... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Show_ASCII_table | Show ASCII table | Task
Show the ASCII character set from values 32 to 127 (decimal) in a table format.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioin... | #Lua | Lua |
-- map of character values to desired representation
local chars = setmetatable({[32] = "Spc", [127] = "Del"}, {__index = function(_, k) return string.char(k) end})
-- row iterator
local function iter(s,a)
a = (a or s) + 16
if a <= 127 then return a, chars[a] end
end
-- print loop
for i = 0, 15 do
for j... | Give a code snippet in #Lua
Task
Show the ASCII character set from values 32 to 127 (decimal) in a table format.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I b... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Color_of_a_screen_pixel | Color of a screen pixel | Task
Get color information from an arbitrary pixel on the screen, such as the current location of the mouse cursor.
The mouse cursor may or may not have to be active in a GUI created by your program. These functions are OS related.
| #Common_Lisp | Common Lisp | (in-package :cg-user)
(defun print-hex (n)
(let ((*print-base* 16.) (*print-radix* t))
(print n)) t)
(defun get-byte (n byte)
(logand (ash n (* byte -8)) #xFF))
(defun get-pixel (x y)
(let ((pixval (caar (contents (get-screen-pixmap :box (make-box x y (+ x 1) (+ y 1)))))))
(mapcar #'(lambda (i) (get... | Give a code snippet in #Common_Lisp
Task
Get color information from an arbitrary pixel on the screen, such as the current location of the mouse cursor.
The mouse cursor may or may not have to be active in a GUI created by your program. These functions are OS related.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Clear_the_screen | Terminal control/Clear the screen | Task
Clear the terminal window.
| #Batch_File | Batch File | CLS | Give a code snippet in #Batch_File
Task
Clear the terminal window.
| 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
... | #BASIC256 | BASIC256 | print "Pop cont (3^x): ";
for i = 0 to 29
print population(3^i); " "; #los últimos números no los muestra correctamente
next i
print : print
print "Evil numbers: ";
call EvilOdious(30, 0)
print : print
print "Odious numbers: ";
call EvilOdious(30, 1)
end
subroutine EvilOdious(limit, type)
i = 0 : cont =... | Give a code snippet in #BASIC256
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 co... | 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... | #TXR | TXR | (defmacro recursive ((. parm-init-pairs) . body)
(let ((hidden-name (gensym "RECURSIVE-")))
^(macrolet ((recurse (. args) ^(,',hidden-name ,*args)))
(labels ((,hidden-name (,*[mapcar first parm-init-pairs]) ,*body))
(,hidden-name ,*[mapcar second parm-init-pairs])))))
(defun fib (number)
(if (... | Give a code snippet in #TXR
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm | Bitmap/Bresenham's line algorithm | Task
Using the data storage type defined on the Bitmap page for raster graphics images,
draw a line given two points with Bresenham's line algorithm.
| #OCaml | OCaml | let draw_line ~img ~color ~p0:(x0,y0) ~p1:(x1,y1) =
let steep = abs(y1 - y0) > abs(x1 - x0) in
let plot =
if steep
then (fun x y -> put_pixel img color y x)
else (fun x y -> put_pixel img color x y)
in
let x0, y0, x1, y1 =
if steep
then y0, x0, y1, x1
else x0, y0, x1, y1
in
let... | Give a code snippet in #OCaml
Task
Using the data storage type defined on the Bitmap page for raster graphics images,
draw a line given two points with Bresenham's line algorithm.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Pi | Pi |
Create a program to continually calculate and output the next decimal digit of
π
{\displaystyle \pi }
(pi).
The program should continue forever (until it is aborted by the user) calculating and outputting each decimal digit in succession.
The output should be a decimal sequence beginning 3.14159265 ...... | #Oforth | Oforth | : calcPiDigits
| q r t k n l |
1 ->q 0 ->r 1 ->t 1 ->k 3 ->n 3 -> l
while( true ) [
4 q * r + t - n t * < ifTrue: [
n print
r n t * - 10 *
3 q * r + 10 * t / n 10 * - ->n ->r
q 10 * ->q
]
else: [
2 q * r + l *
7 k * q * 2 + r l * + t l... | Give a code snippet in #Oforth
Create a program to continually calculate and output the next decimal digit of
π
{\displaystyle \pi }
(pi).
The program should continue forever (until it is aborted by the user) calculating and outputting each decimal digit in succession.
The output should be a decimal seq... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_element_of_a_list | Greatest element of a list | Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| #ColdFusion | ColdFusion |
<Cfset theList = '1, 1000, 250, 13'>
<Cfparam name="maxNum" default=0>
<Cfloop list="#theList#" index="i">
<Cfif i gt maxNum><Cfset maxNum = i></Cfif>
</Cfloop>
<Cfoutput>#maxNum#</Cfoutput>
| Give a code snippet in #ColdFusion
Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Arrays | Arrays | This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrieve an element (if available,... | #NewLISP | NewLISP | (array 5)
→ (nil nil nil nil nil) | Give a code snippet in #NewLISP
This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and ret... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Metronome | Metronome |
The task is to implement a metronome.
The metronome should be capable of producing high and low audio beats, accompanied by a visual beat indicator, and the beat pattern and tempo should be configurable.
For the purpose of this task, it is acceptable to play sound files for production of the beat notes, and an ext... | #Liberty_BASIC | Liberty BASIC | WindowWidth =230
WindowHeight =220
button #w.b1 "Start", [start], LR, 110, 90, 55, 20
button #w.b2 "Tempo", [tempo], LR, 180, 90, 55, 20
button #w.b3 "Pattern", [pattern], LR, 40, 90, 55, 20
open "Metronome" for graphics_nsb_nf as #w
#w "trapclose quit"
#w "down"
#w "... | Give a code snippet in #Liberty_BASIC
The task is to implement a metronome.
The metronome should be capable of producing high and low audio beats, accompanied by a visual beat indicator, and the beat pattern and tempo should be configurable.
For the purpose of this task, it is acceptable to play sound files for p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Higher-order_functions | Higher-order functions | Task
Pass a function as an argument to another function.
Related task
First-class functions
| #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Function square(n As Integer) As Integer
Return n * n
End Function
Function cube(n As Integer) As Integer
Return n * n * n
End Function
Sub doCalcs(from As Integer, upTo As Integer, title As String, func As Function(As Integer) As Integer)
Print title; " -> ";
For i As Integer = from T... | Give a code snippet in #FreeBASIC
Task
Pass a function as an argument to another function.
Related task
First-class functions
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Globally_replace_text_in_several_files | Globally replace text in several files | Task
Replace every occurring instance of a piece of text in a group of text files with another one.
For this task we want to replace the text "Goodbye London!" with "Hello New York!" for a list of files.
| #jq | jq | for file
do
jq -Rr 'gsub($from; $to)' --arg from 'Goodbye London!' --arg to 'Hello New York!' "$file" |
sponge "$file"
done | Give a code snippet in #jq
Task
Replace every occurring instance of a piece of text in a group of text files with another one.
For this task we want to replace the text "Goodbye London!" with "Hello New York!" for a list of files.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Rosetta_Code/Find_unimplemented_tasks | Rosetta Code/Find unimplemented tasks | Task
Given the name of a language on Rosetta Code, find all tasks which are not implemented in that language.
Note: Implementations should allow for fetching more data than can be returned in one request to Rosetta Code.
You'll need to use the Media Wiki API, which you can find out about locally, here, or in Media... | #JavaScript | JavaScript | (function (strXPath) {
var xr = document.evaluate(
strXPath,
document,
null, 0, 0
),
oNode = xr.iterateNext(),
lstTasks = [];
while (oNode) {
lstTasks.push(oNode.title);
oNode = xr.iterateNext();
}
return [
lstTasks.length + " items found in " + document.title,
... | Give a code snippet in #JavaScript
Task
Given the name of a language on Rosetta Code, find all tasks which are not implemented in that language.
Note: Implementations should allow for fetching more data than can be returned in one request to Rosetta Code.
You'll need to use the Media Wiki API, which you can find ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_length | Array length | Task
Determine the amount of elements in an array.
As an example use an array holding the strings 'apple' and 'orange'.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I befo... | #Pony | Pony |
actor Main
new create(env:Env)=>
var c=Array[String](2)
c.push("apple")
c.push("orange")
env.out.print("Array c is " + c.size().string() + " elements long!")
| Give a code snippet in #Pony
Task
Determine the amount of elements in an array.
As an example use an array holding the strings 'apple' and 'orange'.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter freque... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Flow-control_structures | Flow-control structures | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
Document common flow-control structures.
One common example of a flow-control structure is the goto construct.
Note that Conditional Struc... | #BASIC256 | BASIC256 |
gosub subrutina
bucle:
print "Bucle infinito"
goto bucle
subrutina:
print "En subrutina"
pause 10
return
end
| Give a code snippet in #BASIC256
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
Document common flow-control structures.
One common example of a flow-control structure is the goto constru... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_and_product_of_an_array | Sum and product of an array | Task
Compute the sum and product of an array of integers.
| #Ol | Ol |
(print (fold + 0 '(1 2 3 4 5)))
(print (fold * 1 '(1 2 3 4 5)))
| Give a code snippet in #Ol
Task
Compute the sum and product of an array of integers.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Calendar | Calendar | Create a routine that will generate a text calendar for any year.
Test the calendar by generating a calendar for the year 1969, on a device of the time.
Choose one of the following devices:
A line printer with a width of 132 characters.
An IBM 3278 model 4 terminal (80×43 display with accented characters). Target fo... | #Wren | Wren | import "/date" for Date
import "/fmt" for Fmt
import "/seq" for Lst
var calendar = Fn.new { |year|
var snoopy = "🐶"
var days = "Su Mo Tu We Th Fr Sa"
var months = [
"January", "February", "March", "April", "May", "June",
"July", "August", "September", "October", "November", "December"
... | Give a code snippet in #Wren
Create a routine that will generate a text calendar for any year.
Test the calendar by generating a calendar for the year 1969, on a device of the time.
Choose one of the following devices:
A line printer with a width of 132 characters.
An IBM 3278 model 4 terminal (80×43 display with a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Check_input_device_is_a_terminal | Check input device is a terminal | Task
Demonstrate how to check whether the input device is a terminal or not.
Related task
Check output device is a terminal
| #REXX | REXX | /*REXX program determines if input comes from terminal or standard input*/
if queued() then say 'input comes from the terminal.'
else say 'input comes from the (stacked) terminal queue.'
/*stick a fork in it, we're done.*/
| Give a code snippet in #REXX
Task
Demonstrate how to check whether the input device is a terminal or not.
Related task
Check output device is a terminal
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Motzkin_numbers | Motzkin numbers | Definition
The nth Motzkin number (denoted by M[n]) is the number of different ways of drawing non-intersecting chords between n points on a circle (not necessarily touching every point by a chord).
By convention M[0] = 1.
Task
Compute and show on this page the first 42 Motzkin numbers or, if your language does not... | #REXX | REXX | /*REXX program to display the first N Motzkin numbers, and if that number is prime. */
numeric digits 92 /*max number of decimal digits for task*/
parse arg n . /*obtain optional argument from the CL.*/
if n=='' | n=="," then n= 42 ... | Give a code snippet in #REXX
Definition
The nth Motzkin number (denoted by M[n]) is the number of different ways of drawing non-intersecting chords between n points on a circle (not necessarily touching every point by a chord).
By convention M[0] = 1.
Task
Compute and show on this page the first 42 Motzkin numbers... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Wireworld | Wireworld | Wireworld
Conway's Game of Life
It is capable of doing sophisticated computations with appropriate programs
(it is actually Turing complete),
and is much simpler to program for.
A Wireworld arena consists of a Cartesian grid of cells,
each of which can be in one of four states.
All cell transitions happen simultaneous... | #C.23 | C# | #include <ggi/ggi.h>
#include <set>
#include <map>
#include <utility>
#include <iostream>
#include <fstream>
#include <string>
#include <unistd.h> // for usleep
enum cell_type { none, wire, head, tail };
// *****************
// * display class *
// *****************
// this is just a small wrapper for the ggi i... | Give a code snippet in #C.23
Wireworld
Conway's Game of Life
It is capable of doing sophisticated computations with appropriate programs
(it is actually Turing complete),
and is much simpler to program for.
A Wireworld arena consists of a Cartesian grid of cells,
each of which can be in one of four states.
All cell t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Execute_SNUSP | Execute SNUSP | Execute SNUSP is an implementation of SNUSP.
Other implementations of SNUSP.
RCSNUSP
SNUSP
An implementation need only properly implement the Core SNUSP instructions ('$', '\', '/', '+', '-', '<', '>', ',', '.', '!', and '?'). Modular SNUSP ('#', '@') and Bloated SNUSP (':', ';', '%', and '&') are also allowed, but not... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | import strutils
# Requires 5 bytes of data store.
const Hw = r"""
/++++!/===========?\>++.>+.+++++++..+++\
\+++\ | /+>+++++++>/ /++++++++++<<.++>./
$+++/ | \+++++++++>\ \+++++.>.+++.-----\
\==-<<<<+>+++/ /=.>.+>.--------.-/"""
#----------------------------------------------------------------------------------... | Give a code snippet in #Mathematica.2FWolfram_Language
Execute SNUSP is an implementation of SNUSP.
Other implementations of SNUSP.
RCSNUSP
SNUSP
An implementation need only properly implement the Core SNUSP instructions ('$', '\', '/', '+', '-', '<', '>', ',', '.', '!', and '?'). Modular SNUSP ('#', '@') and Bloated ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Animation | Animation |
Animation is integral to many parts of GUIs, including both the fancy effects when things change used in window managers, and of course games. The core of any animation system is a scheme for periodically changing the display while still remaining responsive to the user. This task demonstrates this.
Task
Creat... | #MAXScript | MAXScript |
try destroydialog animGUI catch ()
global userDirection = "right"
fn reverseStr str: direction: =
(
local lastChar = str[str.count]
local firstChar = str[1]
local newStr = ""
local dir
if direction == unsupplied then dir = "left" else dir = direction
case dir of
(
"right": (newstr = lastChar + (subs... | Give a code snippet in #MAXScript
Animation is integral to many parts of GUIs, including both the fancy effects when things change used in window managers, and of course games. The core of any animation system is a scheme for periodically changing the display while still remaining responsive to the user. This tas... | christopher/rosetta-code | |
http://rosettacode.org/wiki/OpenGL | OpenGL |
Task
Display a smooth shaded triangle with OpenGL.
Triangle created using C example compiled with GCC 4.1.2 and freeglut3.
| #AutoHotkey | AutoHotkey | hOpenGL32 := DllCall("LoadLibrary", "Str", "opengl32")
Gui, +LastFound +Resize
hDC := DllCall("GetDC", "uInt", WinExist())
VarSetCapacity(pfd, 40, 0)
NumPut(40, pfd, 0, "uShort")
NumPut(1, pfd, 2, "uShort")
NumPut(37, pfd, 4, "uInt")
NumPut(24, pfd, 9, "uChar")
NumPut(16, pfd, 23, "uChar")
DllCall("SetPixelFormat", "... | Give a code snippet in #AutoHotkey
Task
Display a smooth shaded triangle with OpenGL.
Triangle created using C example compiled with GCC 4.1.2 and freeglut3.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #SETL | SETL | xs := {1..10};
evens := {x in xs | even( x )};
odds := {x in xs | odd( x )};
print( evens );
print( odds ); | Give a code snippet in #SETL
Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divid... | 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... | #ALGOL_68 | ALGOL 68 | PROC fibonacci = ( INT x )INT:
IF x < 0
THEN
print( ( "negative parameter to fibonacci", newline ) );
stop
ELSE
PROC actual fibonacci = ( INT n )INT:
IF n < 2
THEN
n
ELSE
actual fibonacci( n - 1 ) + actual... | Give a code snippet in #ALGOL_68
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 unw... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Downward_for | Loops/Downward for | Task
Write a for loop which writes a countdown from 10 to 0.
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 loop body... | #Vedit_macro_language | Vedit macro language | for (#1 = 10; #1 >= 0; #1--) {
Num_Type(#1)
} | Give a code snippet in #Vedit_macro_language
Task
Write a for loop which writes a countdown from 10 to 0.
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
... | 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... | #APL | APL |
agd←{(⍺-⍵)<10*¯8:⍺⋄((⍺+⍵)÷2)∇(⍺×⍵)*÷2}
1 agd ÷2*÷2
| Give a code snippet in #APL
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/Bitmap/Midpoint_circle_algorithm | Bitmap/Midpoint circle algorithm | Task
Using the data storage type defined on this page for raster images,
write an implementation of the midpoint circle algorithm (also known as Bresenham's circle algorithm).
(definition on Wikipedia).
| #XPL0 | XPL0 | include c:\cxpl\codes; \include 'code' declarations
proc Circle(X0, Y0, Radius, Color); \Display a circle
int X0, Y0, \coordinates of center
Radius, \radius in (pixels)
Color; \line color
int X, Y, E, U, V;
proc PlotOctants; \Segment
[Point(X0+Y, Y0+X... | Give a code snippet in #XPL0
Task
Using the data storage type defined on this page for raster images,
write an implementation of the midpoint circle algorithm (also known as Bresenham's circle algorithm).
(definition on Wikipedia).
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Cursor_movement | Terminal control/Cursor movement | Task
Demonstrate how to achieve movement of the terminal cursor:
how to move the cursor one position to the left
how to move the cursor one position to the right
how to move the cursor up one line (without affecting its horizontal position)
how to move the cursor down one line (without affecting its horizontal po... | #Kotlin | Kotlin | // version 1.1.2
const val ESC = "\u001B" // escape code
fun main(args: Array<String>) {
print("$ESC[2J") // clear terminal first
print("$ESC[10;10H") // move cursor to (10, 10) say
val aecs = arrayOf(
"[1D", // left
"[1C", // right
"[1A", // up
"[1B", //... | Give a code snippet in #Kotlin
Task
Demonstrate how to achieve movement of the terminal cursor:
how to move the cursor one position to the left
how to move the cursor one position to the right
how to move the cursor up one line (without affecting its horizontal position)
how to move the cursor down one line (wit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Convert_seconds_to_compound_duration | Convert seconds to compound duration | Task
Write a function or program which:
takes a positive integer representing a duration in seconds as input (e.g., 100), and
returns a string which shows the same duration decomposed into:
weeks,
days,
hours,
minutes, and
seconds.
This is detailed below (e.g., "2 hr, 59 sec").
Demonstrat... | #Prolog | Prolog | :- use_module(library(clpfd)).
% helper to perform the operation with just a number.
compound_time(N) :-
times(N, R),
format('~p: ', N),
write_times(R).
% write out the results in the 'special' format.
write_times([[Tt, Val]|T]) :-
dif(T, []),
format('~w ~w, ', [Val, Tt]),
write_times(T).
wr... | Give a code snippet in #Prolog
Task
Write a function or program which:
takes a positive integer representing a duration in seconds as input (e.g., 100), and
returns a string which shows the same duration decomposed into:
weeks,
days,
hours,
minutes, and
seconds.
This is detailed below (e.g.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Here_document | Here document | A here document (or "heredoc") is a way of specifying a text block, preserving the line breaks, indentation and other whitespace within the text.
Depending on the language being used, a here document is constructed using a command followed by "<<" (or some other symbol) followed by a token string.
The text ... | #Ring | Ring |
text ="
<<'FOO'
Now
is
the
time
for
all
good mem
to come to the aid of their country."
see text + nl
| Give a code snippet in #Ring
A here document (or "heredoc") is a way of specifying a text block, preserving the line breaks, indentation and other whitespace within the text.
Depending on the language being used, a here document is constructed using a command followed by "<<" (or some other symbol) followed... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Cocktail_sort | Sorting algorithms/Cocktail 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
... | #VBA | VBA | Function cocktail_sort(ByVal s As Variant) As Variant
Dim swapped As Boolean
Dim f As Integer, t As Integer, d As Integer, tmp As Integer
swapped = True
f = 1
t = UBound(s) - 1
d = 1
Do While swapped
swapped = 0
For i = f To t Step d
If Val(s(i)) > Val(s(i + 1)) T... | Give a code snippet in #VBA
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/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... | #Euler_Math_Toolbox | Euler Math Toolbox |
>file="test.png";
>A=loadrgb(file); ...
>insrgb(A);
>function floodfill (A0,i,j,color,dist) ...
$ A=A0;
$ R=getred(A); G=getgreen(A); B=getblue(A);
$ d=sqrt((R-R[i,j])^2+(G-G[i,j])^2+(B-B[i,j])^2);
$ n=rows(A); m=cols(A);
$ V=zeros(n,m);
$ S=zeros(n*m,2); sn=0;
$ A[i,j]=color; V[i,j]=1;
$ repeat;
$ if fill... | Give a code snippet in #Euler_Math_Toolbox
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_unique_characters | Determine if a string has all unique characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are unique
indicate if or which character is duplicated and where
display each string and its length (as the strings are being ... | #ALGOL_68 | ALGOL 68 | BEGIN
# mode to hold the positions of duplicate characters in a string #
MODE DUPLICATE = STRUCT( INT original, first duplicate );
# finds the first non-unique character in s and returns its position #
# and the position of the original character in a DUPLICATE #
# if all characters... | Give a code snippet in #ALGOL_68
Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are unique
indicate if or which character is duplicated and where
display each string and its l... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Take_notes_on_the_command_line | Take notes on the command line | Take notes on the command line is part of Short Circuit's Console Program Basics selection.
Invoking NOTES without commandline arguments displays the current contents of the local NOTES.TXT if it exists.
If NOTES has arguments, the current date and time are appended to the local NOTES.TXT followed by a newline.
Then al... | #BBC_BASIC | BBC BASIC | REM!Exefile C:\NOTES.EXE, encrypt, console
REM!Embed
LF = 10
SYS "GetStdHandle", -10 TO @hfile%(1)
SYS "GetStdHandle", -11 TO @hfile%(2)
SYS "SetConsoleMode", @hfile%(1), 0
*INPUT 13
*OUTPUT 14
ON ERROR PRINT REPORT$ : QUIT ERR
notes% = OPENUP(@dir$ + "NOT... | Give a code snippet in #BBC_BASIC
Take notes on the command line is part of Short Circuit's Console Program Basics selection.
Invoking NOTES without commandline arguments displays the current contents of the local NOTES.TXT if it exists.
If NOTES has arguments, the current date and time are appended to the local NOTES... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Comments | Comments | Task
Show all ways to include text in a language source file
that's completely ignored by the compiler or interpreter.
Related tasks
Documentation
Here_document
See also
Wikipedia
xkcd (Humor: hand gesture denoting // for "commenting out" people.)
| #ECL | ECL | // this is a one-line comment | Give a code snippet in #ECL
Task
Show all ways to include text in a language source file
that's completely ignored by the compiler or interpreter.
Related tasks
Documentation
Here_document
See also
Wikipedia
xkcd (Humor: hand gesture denoting // for "commenting out" people.)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Subleq | Subleq | Subleq is an example of a One-Instruction Set Computer (OISC).
It is named after its only instruction, which is SUbtract and Branch if Less than or EQual to zero.
Task
Your task is to create an interpreter which emulates a SUBLEQ machine.
The machine's memory consists of an array of signed integers. These integers... | #Sidef | Sidef | var memory = ARGV.map{.to_i};
var ip = 0;
while (ip.ge(0) && ip.lt(memory.len)) {
var (a, b, c) = memory[ip, ip+1, ip+2];
ip += 3;
if (a < 0) {
memory[b] = STDIN.getc.ord;
}
elsif (b < 0) {
print memory[a].chr;
}
elsif ((memory[b] -= memory[a]) <= 0) {
ip = c
}
... | Give a code snippet in #Sidef
Subleq is an example of a One-Instruction Set Computer (OISC).
It is named after its only instruction, which is SUbtract and Branch if Less than or EQual to zero.
Task
Your task is to create an interpreter which emulates a SUBLEQ machine.
The machine's memory consists of an array of si... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_length | Array length | Task
Determine the amount of elements in an array.
As an example use an array holding the strings 'apple' and 'orange'.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I befo... | #MiniZinc | MiniZinc |
array[int] of int: arr = [1,2,3];
var int: size = length(arr);
solve satisfy;
output [show(size),"\n"];
| Give a code snippet in #MiniZinc
Task
Determine the amount of elements in an array.
As an example use an array holding the strings 'apple' and 'orange'.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter fr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Catalan_numbers | Catalan numbers | Catalan numbers
You are encouraged to solve this task according to the task description, using any language you may know.
Catalan numbers are a sequence of numbers which can be defined directly:
C
n
=
1
n
+
1
(
2
n
n
)
=
(
2
n
)
!
(
n
+
1
)
!
n
!
for
n
≥
0.
{\displaystyle C... | #Harbour | Harbour |
PROCEDURE Main()
LOCAL i
FOR i := 0 to 15
? PadL( i, 2 ) + ": " + hb_StrFormat("%d", Catalan( i ))
NEXT
RETURN
STATIC FUNCTION Catalan( n )
LOCAL i, nCatalan := 1
FOR i := 1 TO n
nCatalan := nCatalan * 2 * (2 * i - 1) / (i + 1)
NEXT
RETURN nCatalan
| Give a code snippet in #Harbour
Catalan numbers
You are encouraged to solve this task according to the task description, using any language you may know.
Catalan numbers are a sequence of numbers which can be defined directly:
C
n
=
1
n
+
1
(
2
n
n
)
=
(
2
n
)
!
(
n
+
1
)
!
n
!
... | 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... | #AutoHotkey | AutoHotkey | ; Initially build the board
Width := 11
Height := 8
Loop % height*2+1
{
Outer := A_Index
Loop % Width
maze .= Outer & 1 ? "+-" : "|0"
maze .= (Outer & 1 ? "+" : "|") "`n"
}
StringTrimRight, maze, maze, 1 ; removes trailing newline
Clipboard := Walk(maze)
Walk(S, x=0, y=0){
If !x{ ; --Start at a random cell...
... | Give a code snippet in #AutoHotkey
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cholesky_decomposition | Cholesky decomposition | Every symmetric, positive definite matrix A can be decomposed into a product of a unique lower triangular matrix L and its transpose:
A
=
L
L
T
{\displaystyle A=LL^{T}}
L
{\displaystyle L}
is called the Cholesky factor of
A
{\displaystyle A}
, and can be interpreted as a generalized square r... | #Rust | Rust | fn cholesky(mat: Vec<f64>, n: usize) -> Vec<f64> {
let mut res = vec![0.0; mat.len()];
for i in 0..n {
for j in 0..(i+1){
let mut s = 0.0;
for k in 0..j {
s += res[i * n + k] * res[j * n + k];
}
res[i * n + j] = if i == j { (mat[i * n + i] ... | Give a code snippet in #Rust
Every symmetric, positive definite matrix A can be decomposed into a product of a unique lower triangular matrix L and its transpose:
A
=
L
L
T
{\displaystyle A=LL^{T}}
L
{\displaystyle L}
is called the Cholesky factor of
A
{\displaystyle A}
, and can be interpr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/N-queens_problem | N-queens problem |
Solve the eight queens puzzle.
You can extend the problem to solve the puzzle with a board of size NxN.
For the number of solutions for small values of N, see OEIS: A000170.
Related tasks
A* search algorithm
Solve a Hidato puzzle
Solve a Holy Knight's tour
Knight's tour
Peaceful chess queen armie... | #AppleScript | AppleScript | -- Finds all possible solutions and the unique patterns.
property Grid_Size : 8
property Patterns : {}
property Solutions : {}
property Test_Count : 0
property Rotated : {}
on run
local diff
local endTime
local msg
local rows
local startTime
set Patterns to {}
set Solutions to {}
... | Give a code snippet in #AppleScript
Solve the eight queens puzzle.
You can extend the problem to solve the puzzle with a board of size NxN.
For the number of solutions for small values of N, see OEIS: A000170.
Related tasks
A* search algorithm
Solve a Hidato puzzle
Solve a Holy Knight's tour
Knig... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sudoku | Sudoku | Task
Solve a partially filled-in normal 9x9 Sudoku grid and display the result in a human-readable format.
references
Algorithmics of Sudoku may help implement this.
Python Sudoku Solver Computerphile video.
| #Golfscript | Golfscript |
'Solution:'
;'2 8 4 3 7 5 1 6 9
0 0 9 2 0 0 0 0 7
0 0 1 0 0 4 0 0 2
0 5 0 0 0 0 8 0 0
0 0 8 0 0 0 9 0 0
0 0 6 0 0 0 0 4 0
9 0 0 1 0 0 5 0 0
8 0 0 0 0 7 6 0 4
4 2 5 6 8 9 7 3 1'
{9/[n]*puts}:p; #optional formatting
~]{:@0?:^~!{@p}*10,@9/^9/=-@^9%>9%-@3/^9%3/>3%3/^27/={+}*-{@^<\+@1^+>+}/1}do
| Give a code snippet in #Golfscript
Task
Solve a partially filled-in normal 9x9 Sudoku grid and display the result in a human-readable format.
references
Algorithmics of Sudoku may help implement this.
Python Sudoku Solver Computerphile video.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number/With_feedback_(player) | Guess the number/With feedback (player) | Task
Write a player for the game that follows the following rules:
The scorer will choose a number between set limits. The computer player will print a guess of the target number. The computer asks for a score of whether its guess is higher than, lower than, or equal to the target. The computer guesses, and the score... | #PARI.2FGP | PARI/GP |
guessnumber2(b)={
my(c=0,d=b,a=0);
for(x=1,b,
for(y=1,b,
if(a<c||a==c||a==d||a>d,
a=random(b),
break()
)
);
print("I guess "a" am I h,l,or e ?");
g=input();
if(g==h,
d=a,
if(g==l,
c=a,
if(g==e,
break()
)
... | Give a code snippet in #PARI.2FGP
Task
Write a player for the game that follows the following rules:
The scorer will choose a number between set limits. The computer player will print a guess of the target number. The computer asks for a score of whether its guess is higher than, lower than, or equal to the target. ... | 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... | #HolyC | HolyC | Print("%d\n", 'a'); /* prints "97" */
Print("%c\n", 97); /* prints "a" */ | Give a code snippet in #HolyC
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).
Conv... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Last_letter-first_letter | Last letter-first letter | A certain children's game involves starting with a word in a particular category. Each participant in turn says a word, but that word must begin with the final letter of the previous word. Once a word has been given, it cannot be repeated. If an opponent cannot give a word in the category, they fall out of the ga... | #Ada | Ada | with Ada.Containers.Indefinite_Vectors, Ada.Text_IO;
procedure Lalefile is
package Word_Vec is new Ada.Containers.Indefinite_Vectors
(Index_Type => Positive,
Element_Type => String);
use type Word_Vec.Vector, Ada.Containers.Count_Type;
type Words_Type is array (Character) of Word_Vec.Vecto... | Give a code snippet in #Ada
A certain children's game involves starting with a word in a particular category. Each participant in turn says a word, but that word must begin with the final letter of the previous word. Once a word has been given, it cannot be repeated. If an opponent cannot give a word in the cate... | christopher/rosetta-code |
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