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/Search_a_list | Search a list | Task[edit]
Find the index of a string (needle) in an indexable, ordered collection of strings (haystack).
Raise an exception if the needle is missing.
If there is more than one occurrence then return the smallest index to the needle.
Extra credit
Return the largest index to a needle that has multiple occurrences in ... | #C | C | #include <stdio.h>
#include <string.h>
const char *haystack[] = {
"Zig", "Zag", "Wally", "Ronald", "Bush", "Krusty", "Charlie",
"Bush", "Boz", "Zag", NULL
};
int search_needle(const char *needle, const char **hs)
{
int i = 0;
while( hs[i] != NULL ) {
if ( strcmp(hs[i], needle) == 0 ) return i;
i++;
... | Give a code snippet in #C
Task[edit]
Find the index of a string (needle) in an indexable, ordered collection of strings (haystack).
Raise an exception if the needle is missing.
If there is more than one occurrence then return the smallest index to the needle.
Extra credit
Return the largest index to a needle that h... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Make_directory_path | Make directory path | Task
Create a directory and any missing parents.
This task is named after the posix mkdir -p command, and several libraries which implement the same behavior.
Please implement a function of a single path string (for example ./path/to/dir) which has the above side-effect.
If the directory already exists, return succe... | #Kotlin | Kotlin | // version 1.0.6
import java.io.File
fun main(args: Array<String>) {
// using built-in mkdirs() method
val success = File("./path/to/dir").mkdirs()
if (success) println("Directory path was created successfully")
else println("Failed to create directory path")
} | Give a code snippet in #Kotlin
Task
Create a directory and any missing parents.
This task is named after the posix mkdir -p command, and several libraries which implement the same behavior.
Please implement a function of a single path string (for example ./path/to/dir) which has the above side-effect.
If the direct... | 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... | #Kotlin | Kotlin | // version 1.1.51
typealias Matrix = Array<DoubleArray>
/* changes the matrix to RREF 'in place' */
fun Matrix.toReducedRowEchelonForm() {
var lead = 0
val rowCount = this.size
val colCount = this[0].size
for (r in 0 until rowCount) {
if (colCount <= lead) return
var i = r
... | Give a code snippet in #Kotlin
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 convenie... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Display_an_extended_character | Terminal control/Display an extended character | Task
Display an extended (non ASCII) character onto the terminal.
Specifically, display a £ (GBP currency sign).
| #REXX | REXX | /*REXX program demonstrates displaying an extended character (glyph) to the terminal.*/
/* [↓] this SAY will display the £ glyph (if the term supports it).*/
say '£' /*this assumes the pound sign glyph is displayable on the terminal. */
/*this program can execute c... | Give a code snippet in #REXX
Task
Display an extended (non ASCII) character onto the terminal.
Specifically, display a £ (GBP currency sign).
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case... | #BQN | BQN | •file.Chars "file"
•file.Bytes "file"
# Shorthands:
•FChars "file"
•FBytes "file"
| Give a code snippet in #BQN
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished increme... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Primality_by_trial_division | Primality by trial division | Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loops are allowed.
Related tasks
... | #Factor | Factor | USING: combinators kernel math math.functions math.ranges sequences ;
: prime? ( n -- ? )
{
{ [ dup 2 < ] [ drop f ] }
{ [ dup even? ] [ 2 = ] }
[ 3 over sqrt 2 <range> [ mod 0 > ] with all? ]
} cond ; | Give a code snippet in #Factor
Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loop... | christopher/rosetta-code | |
http://rosettacode.org/wiki/K-d_tree | K-d tree |
This page uses content from Wikipedia. The original article was at K-d tree. 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)
A k-d tree (short for k-dimensional tree) is a space-partitioning data str... | #Nim | Nim | type
Point[Dim: static Natural; T: SomeNumber] = array[Dim, T]
KdNode[Dim: static Natural; T: SomeNumber] = ref object
x: Point[Dim, T]
left, right: KdNode[Dim, T]
func toKdNodes[N, Dim: static Natural; T](a: array[N, array[Dim, T]]): array[N, KdNode[Dim, T]] =
## Create an array of KdNodes from a... | Give a code snippet in #Nim
This page uses content from Wikipedia. The original article was at K-d tree. 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)
A k-d tree (short for k-dimensional tree) is ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Jaro-Winkler_distance | Jaro-Winkler distance | The Jaro-Winkler distance is a metric for measuring the edit distance between words.
It is similar to the more basic Levenstein distance but the Jaro distance also accounts
for transpositions between letters in the words. With the Winkler modification to the Jaro
metric, the Jaro-Winkler distance also adds an increase ... | #Wren | Wren | import "io" for File
import "/fmt" for Fmt
import "/sort" for Sort
var jaroSim = Fn.new { |s1, s2|
var le1 = s1.count
var le2 = s2.count
if (le1 == 0 && le2 == 0) return 1
if (le1 == 0 || le2 == 0) return 0
var dist = (le2 > le1) ? le2 : le1
dist = (dist/2).floor - 1
var matches1 = List.fi... | Give a code snippet in #Wren
The Jaro-Winkler distance is a metric for measuring the edit distance between words.
It is similar to the more basic Levenstein distance but the Jaro distance also accounts
for transpositions between letters in the words. With the Winkler modification to the Jaro
metric, the Jaro-Winkler d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Wee_Basic | Wee Basic | include c:\cxpl\codes; \intrinsic 'code' declarations
int I;
[RanSeed(12345); \set random number generator seed to 12345
for I:= 1 to 5 do
[IntOut(0, Ran(1_000_000)); CrLf(0)];
] | Give a code snippet in #Wee_Basic
The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Singly-linked_list/Element_definition | Singly-linked list/Element definition | singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, Lis... | #PL.2FI | PL/I |
declare 1 node based (p),
2 value fixed,
2 link pointer;
| Give a code snippet in #PL.2FI
singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element de... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Colour_bars/Display | Colour bars/Display | Task
Display a series of vertical color bars across the width of the display.
The color bars should either use:
the system palette, or
the sequence of colors:
black
red
green
blue
magenta
cyan
yellow
white
| #Icon_and_Unicon | Icon and Unicon | link graphics,printf
procedure main() # generalized colour bars
DrawTestCard(Simple_TestCard())
WDone()
end
procedure DrawTestCard(TC)
size := sprintf("size=%d,%d",TC.width,TC.height)
&window := TC.window := open(TC.id,"g","bg=black",size) |
stop("Unable to open window")
eve... | Give a code snippet in #Icon_and_Unicon
Task
Display a series of vertical color bars across the width of the display.
The color bars should either use:
the system palette, or
the sequence of colors:
black
red
green
blue
magenta
cyan
yellow
white
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Modular_exponentiation | Modular exponentiation | Find the last 40 decimal digits of
a
b
{\displaystyle a^{b}}
, where
a
=
2988348162058574136915891421498819466320163312926952423791023078876139
{\displaystyle a=2988348162058574136915891421498819466320163312926952423791023078876139}
b
=
235139930337346448646612254452369009474497523... | #Wren | Wren | import "/big" for BigInt
var a = BigInt.new("2988348162058574136915891421498819466320163312926952423791023078876139")
var b = BigInt.new("2351399303373464486466122544523690094744975233415544072992656881240319")
var m = BigInt.ten.pow(40)
System.print(a.modPow(b, m)) | Give a code snippet in #Wren
Find the last 40 decimal digits of
a
b
{\displaystyle a^{b}}
, where
a
=
2988348162058574136915891421498819466320163312926952423791023078876139
{\displaystyle a=2988348162058574136915891421498819466320163312926952423791023078876139}
b
=
235139930337346... | 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
| #Excel | Excel | thueMorse
=LAMBDA(n,
APPLYN(n)(
LAMBDA(bits,
APPENDCOLS(bits)(
LAMBDA(x,
IF(0 < x, 0, 1)
)(bits)
)
)
)(0)
) | Give a code snippet in #Excel
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/Y_combinator | Y combinator | In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions.
This rules out the usual definition of a recursive function wherein a function is associated with the state of a variable and this variable's stat... | #Ruby | Ruby | y = lambda do |f|
lambda {|g| g[g]}[lambda do |g|
f[lambda {|*args| g[g][*args]}]
end]
end
fac = lambda{|f| lambda{|n| n < 2 ? 1 : n * f[n-1]}}
p Array.new(10) {|i| y[fac][i]} #=> [1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880]
fib = lambda{|f| lambda{|n| n < 2 ? n : f[n-1] + f[n-2]}}
p Array.new(10) ... | Give a code snippet in #Ruby
In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions.
This rules out the usual definition of a recursive function wherein a function is associated with the state of a var... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Abbreviations,_automatic | Abbreviations, automatic | The use of abbreviations (also sometimes called synonyms, nicknames, AKAs, or aliases) can be an
easy way to add flexibility when specifying or using commands, sub─commands, options, etc.
It would make a list of words easier to maintain (as words are added, changed, and/or deleted) if
the minimum abbrevia... | #Phix | Phix | constant lines = get_text("abbrev_auto.txt",GT_LF_STRIPPED)
for i=1 to length(lines) do
string li = lines[i]
if length(li) then
sequence days = split(li,no_empty:=true)
if length(days)!=7 then ?9/0 end if
integer len = 1
for j=1 to 7 do
for k=j+1 to 7 do
... | Give a code snippet in #Phix
The use of abbreviations (also sometimes called synonyms, nicknames, AKAs, or aliases) can be an
easy way to add flexibility when specifying or using commands, sub─commands, options, etc.
It would make a list of words easier to maintain (as words are added, changed, and/or dele... | 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... | #Go | Go | package main
import (
"fmt"
"time"
"os"
"os/exec"
"strconv"
)
func main() {
tput("clear") // clear screen
tput("cup", "6", "3") // an initial position
time.Sleep(1 * time.Second)
tput("cub1") // left
time.Sleep(1 * time.Second)
tput("cuf1") // right
time.Sleep(1 * tim... | Give a code snippet in #Go
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Substring/Top_and_tail | Substring/Top and tail | The task is to demonstrate how to remove the first and last characters from a string.
The solution should demonstrate how to obtain the following results:
String with first character removed
String with last character removed
String with both the first and last characters removed
If the program uses UTF-8 or UTF... | #Clojure | Clojure | ; using substring:
user=> (subs "knight" 1)
"night"
user=> (subs "socks" 0 4)
"sock"
user=> (.substring "brooms" 1 5)
"room"
; using rest and drop-last:
user=> (apply str (rest "knight"))
"night"
user=> (apply str (drop-last "socks"))
"sock"
user=> (apply str (rest (drop-last "brooms")))
"room" | Give a code snippet in #Clojure
The task is to demonstrate how to remove the first and last characters from a string.
The solution should demonstrate how to obtain the following results:
String with first character removed
String with last character removed
String with both the first and last characters removed
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_in_octal | Count in octal | Task
Produce a sequential count in octal, starting at zero, and using an increment of a one for each consecutive number.
Each number should appear on a single line, and the program should count until terminated, or until the maximum value of the numeric type in use is reached.
Related task
Integer sequ... | #FutureBasic | FutureBasic | window 1, @"Count in Octal"
defstr word
dim as short i
text ,,,,, 50
print @"dec",@"oct"
for i = 0 to 25
print i,oct(i)
next
HandleEvents | Give a code snippet in #FutureBasic
Task
Produce a sequential count in octal, starting at zero, and using an increment of a one for each consecutive number.
Each number should appear on a single line, and the program should count until terminated, or until the maximum value of the numeric type in use is reac... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Horizontal_sundial_calculations | Horizontal sundial calculations | Task
Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location.
For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island, aka Ernest Legouve Reef), wit... | #Java | Java | import java.util.Scanner;
public class Sundial {
public static void main(String[] args) {
double lat, slat, lng, ref;
Scanner sc = new Scanner(System.in);
System.out.print("Enter latitude: ");
lat = sc.nextDouble();
System.out.print("Enter longitude: ");
lng = sc.... | Give a code snippet in #Java
Task
Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location.
For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Wieferich_primes | Wieferich primes |
This page uses content from Wikipedia. The original article was at Wieferich prime. 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)
In number theory, a Wieferich prime is a prime number p such th... | #Raku | Raku | put "Wieferich primes less than 5000: ", join ', ', ^5000 .grep: { .is-prime and not ( exp($_-1, 2) - 1 ) % .² }; | Give a code snippet in #Raku
This page uses content from Wikipedia. The original article was at Wieferich prime. 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)
In number theory, a Wieferich prime... | 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... | #C.2B.2B | C++ | #include <fstream>
#include <iostream>
#include <ctime>
using namespace std;
#define note_file "NOTES.TXT"
int main(int argc, char **argv)
{
if(argc>1)
{
ofstream Notes(note_file, ios::app);
time_t timer = time(NULL);
if(Notes.is_open())
{
Notes << asctime(localtime(&timer)) << '\t';
for(int i=1;i<a... | Give a code snippet in #C.2B.2B
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.T... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bioinformatics/Sequence_mutation | Bioinformatics/Sequence mutation | Task
Given a string of characters A, C, G, and T representing a DNA sequence write a routine to mutate the sequence, (string) by:
Choosing a random base position in the sequence.
Mutate the sequence by doing one of either:
Swap the base at that position by changing it to one of A, C, G, or T. (which has a chance o... | #Go | Go | package main
import (
"fmt"
"math/rand"
"sort"
"time"
)
const bases = "ACGT"
// 'w' contains the weights out of 300 for each
// of swap, delete or insert in that order.
func mutate(dna string, w [3]int) string {
le := len(dna)
// get a random position in the dna to mutate
p := rand.Int... | Give a code snippet in #Go
Task
Given a string of characters A, C, G, and T representing a DNA sequence write a routine to mutate the sequence, (string) by:
Choosing a random base position in the sequence.
Mutate the sequence by doing one of either:
Swap the base at that position by changing it to one of A, C, G,... | 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... | #Sed | Sed | #! /bin/sed -nf
# gcd.sed Copyright (c) 2010 by Paweł Zuzelski <pawelz@pld-linux.org>
# dc.sed Copyright (c) 1995 - 1997 by Greg Ubben <gsu@romulus.ncsc.mil>
# usage:
#
# echo N M | ./gcd.sed
#
# Computes the greatest common divisor of N and M integers using euclidean
# algorithm.
s/^/|P|K0|I10|O10|?~... | Give a code snippet in #Sed
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 c... | 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... | #Rust | Rust | fn main() {
let nums = [1,2,39,34,20, -20, -16, 35, 0];
let mut max = 0;
let mut boundaries = 0..0;
for length in 0..nums.len() {
for start in 0..nums.len()-length {
let sum = (&nums[start..start+length]).iter()
.fold(0, |sum, elem| sum+elem);
if sum >... | Give a code snippet in #Rust
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 n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Letter_frequency | Letter frequency | Task
Open a text file and count the occurrences of each letter.
Some of these programs count all characters (including punctuation),
but some only count letters A to Z.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequen... | #JavaScript | JavaScript | (function(txt) {
var cs = txt.split(''),
i = cs.length,
dct = {},
c = '',
keys;
while (i--) {
c = cs[i];
dct[c] = (dct[c] || 0) + 1;
}
keys = Object.keys(dct);
keys.sort();
return keys.map(function (c) { return [c, dct[c]]; });
})("Not all... | Give a code snippet in #JavaScript
Task
Open a text file and count the occurrences of each letter.
Some of these programs count all characters (including punctuation),
but some only count letters A to Z.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Minimum_positive_multiple_in_base_10_using_only_0_and_1 | Minimum positive multiple in base 10 using only 0 and 1 | Every positive integer has infinitely many base-10 multiples that only use the digits 0 and 1. The goal of this task is to find and display the minimum multiple that has this property.
This is simple to do, but can be challenging to do efficiently.
To avoid repeating long, unwieldy phrases, the operation "minimum pos... | #ALGOL_68 | ALGOL 68 | BEGIN
# returns B10 for the specified n or -1 if it cannot be found #
# based on Rick Heylen's C program linked from the OEIS site #
PROC find b10 = ( INT n )LONG INT:
IF n < 1 THEN -1
ELIF n = 1 THEN 1
ELSE
[ 0 : n ]LONG INT pow, val;
INT x, ten... | Give a code snippet in #ALGOL_68
Every positive integer has infinitely many base-10 multiples that only use the digits 0 and 1. The goal of this task is to find and display the minimum multiple that has this property.
This is simple to do, but can be challenging to do efficiently.
To avoid repeating long, unwieldy p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Balanced_ternary | Balanced ternary | Balanced ternary is a way of representing numbers. Unlike the prevailing binary representation, a balanced ternary integer is in base 3, and each digit can have the values 1, 0, or −1.
Examples
Decimal 11 = 32 + 31 − 30, thus it can be written as "++−"
Decimal 6 = 32 − 31 + 0 × 30, thus it can be written as "+−0"
... | #J | J | trigits=: 1+3 <.@^. 2 * 1&>.@|
trinOfN=: |.@((_1 + ] #: #.&1@] + [) #&3@trigits) :. nOfTrin
nOfTrin=: p.&3 :. trinOfN
trinOfStr=: 0 1 _1 {~ '0+-'&i.@|. :. strOfTrin
strOfTrin=: {&'0+-'@|. :. trinOfStr
carry=: +//.@:(trinOfN"0)^:_
trimLead0=: (}.~ i.&1@:~:&0)&.|.
add=: carry@(+/@,:)
neg=: -
mul=: trimLead0@carry@(+/... | Give a code snippet in #J
Balanced ternary is a way of representing numbers. Unlike the prevailing binary representation, a balanced ternary integer is in base 3, and each digit can have the values 1, 0, or −1.
Examples
Decimal 11 = 32 + 31 − 30, thus it can be written as "++−"
Decimal 6 = 32 − 31 + 0 × 30, thus ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multiplication_tables | Multiplication tables | Task
Produce a formatted 12×12 multiplication table of the kind memorized by rote when in primary (or elementary) school.
Only print the top half triangle of products.
| #C.2B.2B | C++ | #include <iostream>
#include <iomanip>
#include <cmath> // for log10()
#include <algorithm> // for max()
size_t table_column_width(const int min, const int max)
{
unsigned int abs_max = std::max(max*max, min*min);
// abs_max is the largest absolute value we might see.
// If we take the log10 and add one... | Give a code snippet in #C.2B.2B
Task
Produce a formatted 12×12 multiplication table of the kind memorized by rote when in primary (or elementary) school.
Only print the top half triangle of products.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Colour_bars/Display | Colour bars/Display | Task
Display a series of vertical color bars across the width of the display.
The color bars should either use:
the system palette, or
the sequence of colors:
black
red
green
blue
magenta
cyan
yellow
white
| #PowerShell | PowerShell |
[string[]]$colors = "Black" , "DarkBlue" , "DarkGreen" , "DarkCyan",
"DarkRed" , "DarkMagenta", "DarkYellow", "Gray",
"DarkGray", "Blue" , "Green" , "Cyan",
"Red" , "Magenta" , "Yellow" , "White"
for ($i = 0; $i -lt 64; $i++)
{
... | Give a code snippet in #PowerShell
Task
Display a series of vertical color bars across the width of the display.
The color bars should either use:
the system palette, or
the sequence of colors:
black
red
green
blue
magenta
cyan
yellow
white
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Luhn_test_of_credit_card_numbers | Luhn test of credit card numbers | The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits.
Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test:
Reverse the order of the digits in the number.
Tak... | #Quackery | Quackery | [ 1 & ] is odd ( n --> b )
[ [] swap
[ 10 /mod
rot join swap
dup 0 = until ]
drop ] is digits ( n --> [ )
[ [] [] rot
dup size odd dip
[ witheach
[ nested join
swap ] ]
not if swap ] is unzip ( [ --> [ [ ... | Give a code snippet in #Quackery
The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits.
Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test:
Reverse the order... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Grayscale_image | Grayscale image | Many image processing algorithms are defined for grayscale (or else monochromatic) images.
Task
Extend the data storage type defined on this page to support grayscale images.
Define two operations, one to convert a color image to a grayscale image and one for the backward conversion.
To get luminance of a color u... | #Forth | Forth | \ grayscale bitmap (without word-alignment for scan lines)
\ bdim, bwidth, bdata all work with graymaps
: graymap ( w h -- gmp )
2dup * bdata allocate throw
dup >r 2! r> ;
: gxy ( x y gmp -- addr )
dup bwidth rot * rot + swap bdata + ;
: g@ ( x y gmp -- c ) gxy c@ ;
: g! ( c x y bmp -- ) gxy c! ;
: gfil... | Give a code snippet in #Forth
Many image processing algorithms are defined for grayscale (or else monochromatic) images.
Task
Extend the data storage type defined on this page to support grayscale images.
Define two operations, one to convert a color image to a grayscale image and one for the backward conversion.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/ABC_problem | ABC problem | ABC problem
You are encouraged to solve this task according to the task description, using any language you may know.
You are given a collection of ABC blocks (maybe like the ones you had when you were a kid).
There are twenty blocks with two letters on each block.
A complete alphabet is guaranteed amongst all sid... | #Kotlin | Kotlin | object ABC_block_checker {
fun run() {
println("\"\": " + blocks.canMakeWord(""))
for (w in words) println("$w: " + blocks.canMakeWord(w))
}
private fun Array<String>.swap(i: Int, j: Int) {
val tmp = this[i]
this[i] = this[j]
this[j] = tmp
}
private fun Ar... | Give a code snippet in #Kotlin
ABC problem
You are encouraged to solve this task according to the task description, using any language you may know.
You are given a collection of ABC blocks (maybe like the ones you had when you were a kid).
There are twenty blocks with two letters on each block.
A complete alphab... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Number_names | Number names | Task
Show how to spell out a number in English.
You can use a preexisting implementation or roll your own, but you should support inputs up to at least one million (or the maximum value of your language's default bounded integer type, if that's less).
Support for inputs other than positive integers (like zero, negat... | #Erlang | Erlang |
-module(nr2eng).
-import(lists, [foreach/2, seq/2, append/2]).
-import(string, [strip/3, str/2]).
-export([start/0]).
sym(1) -> "one";
sym(2) -> "two";
sym(3) -> "three";
sym(4) -> "four";
sym(5) -> "five";
sym(6) -> "six";
sym(7) -> "seven";
sym(8) -> "eight";
sym(9) -> "nine";
sym(10) -> "ten";
sym(11) -> "eleven... | Give a code snippet in #Erlang
Task
Show how to spell out a number in English.
You can use a preexisting implementation or roll your own, but you should support inputs up to at least one million (or the maximum value of your language's default bounded integer type, if that's less).
Support for inputs other than pos... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #Raku | Raku |
my $path = "/etc/passwd";
say $path.IO.e ?? "Exists" !! "Does not exist";
given $path.IO {
when :d { say "$path is a directory"; }
when :f { say "$path is a regular file"; }
when :e { say "$path is neither a directory nor a file, but it does exist"; }
default { say "$path does not exist" }
} | Give a code snippet in #Raku
Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Gnome_sort | Sorting algorithms/Gnome 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
... | #Io | Io | List do(
gnomeSortInPlace := method(
idx := 1
while(idx <= size,
if(idx == 0 or at(idx) > at(idx - 1)) then(
idx = idx + 1
) else(
swapIndices(idx, idx - 1)
idx = idx - 1
)
)
self)
)
lst := list(5, -1, ... | Give a code snippet in #Io
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/Averages/Arithmetic_mean | Averages/Arithmetic mean | Task[edit]
Write a program to find the mean (arithmetic average) of a numeric vector.
In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an established convention for conveyin... | #Erlang | Erlang | mean([]) -> 0;
mean(L) -> lists:sum(L)/erlang:length(L). | Give a code snippet in #Erlang
Task[edit]
Write a program to find the mean (arithmetic average) of a numeric vector.
In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an est... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stair-climbing_puzzle | Stair-climbing puzzle | From Chung-Chieh Shan (LtU):
Your stair-climbing robot has a very simple low-level API: the "step" function takes no argument and attempts to climb one step as a side effect. Unfortunately, sometimes the attempt fails and the robot clumsily falls one step instead. The "step" function detects what happens and returns a... | #Liberty_BASIC | Liberty BASIC | 'This demo will try to get the robot to step up
'Run it several times to see the differences; sometimes the robot falls
'quite a ways before making it to the next step up, but sometimes he makes it
'on the first try
result = Stepp.Up()
Function Stepp.Up()
While Not(Stepp())
result = Stepp.Up()
Wend
... | Give a code snippet in #Liberty_BASIC
From Chung-Chieh Shan (LtU):
Your stair-climbing robot has a very simple low-level API: the "step" function takes no argument and attempts to climb one step as a side effect. Unfortunately, sometimes the attempt fails and the robot clumsily falls one step instead. The "step" func... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Conway%27s_Game_of_Life | Conway's Game of Life | The Game of Life is a cellular automaton devised by the British mathematician John Horton Conway in 1970. It is the best-known example of a cellular automaton.
Conway's game of life is described here:
A cell C is represented by a 1 when alive, or 0 when dead, in an m-by-m (or m×m) sq... | #XSLT | XSLT | <xsl:template match="/table">
<table>
<xsl:apply-templates />
</table>
</xsl:template>
<xsl:template match="tr">
<tr><xsl:apply-templates /></tr>
</xsl:template>
<xsl:template match="td">
<xsl:variable name="liveNeighbours">
<xsl:apply-templates select="current()" mode="countLiveNeig... | Give a code snippet in #XSLT
The Game of Life is a cellular automaton devised by the British mathematician John Horton Conway in 1970. It is the best-known example of a cellular automaton.
Conway's game of life is described here:
A cell C is represented by a 1 when alive, or 0 when dead, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nth_root | Nth root | Task
Implement the algorithm to compute the principal nth root
A
n
{\displaystyle {\sqrt[{n}]{A}}}
of a positive real number A, as explained at the Wikipedia page.
| #BASIC | BASIC | FUNCTION RootX (tBase AS DOUBLE, tExp AS DOUBLE, diffLimit AS DOUBLE) AS DOUBLE
DIM tmp1 AS DOUBLE, tmp2 AS DOUBLE
' Initial guess:
tmp1 = tBase / tExp
DO
tmp2 = tmp1
' 1# tells compiler that "1" is a double, not an integer
tmp1 = (((tExp - 1#) * tmp2) + (tBase / (tmp2 ^ (tExp - ... | Give a code snippet in #BASIC
Task
Implement the algorithm to compute the principal nth root
A
n
{\displaystyle {\sqrt[{n}]{A}}}
of a positive real number A, as explained at the Wikipedia page.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #MATLAB_.2F_Octave | MATLAB / Octave | x='{>\(y>(((-y-(((<(^<ejtq)\{-y.2^*<';z=['x=''',x,''';'];disp([z,x-1]); | Give a code snippet in #MATLAB_.2F_Octave
A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating compute... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Floyd-Warshall_algorithm | Floyd-Warshall algorithm | The Floyd–Warshall algorithm is an algorithm for finding shortest paths in a weighted graph with positive or negative edge weights.
Task
Find the lengths of the shortest paths between all pairs of vertices of the given directed graph. Your code may assume that the input has already been checked for loops, parallel ... | #jq | jq |
def weights: {
"1": {"3": -2},
"2": {"1" : 4, "3": 3},
"3": {"4": 2},
"4": {"2": -1}
}; | Give a code snippet in #jq
The Floyd–Warshall algorithm is an algorithm for finding shortest paths in a weighted graph with positive or negative edge weights.
Task
Find the lengths of the shortest paths between all pairs of vertices of the given directed graph. Your code may assume that the input has already been ... | 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 ... | #C | C | #include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
typedef uint32_t pint;
typedef uint64_t xint;
typedef unsigned int uint;
#define PRIuPINT PRIu32 /* printf macro for pint */
#define PRIuXINT PRIu64 /* printf macro for xint */
#define MAX_FACTORS 63 /* b... | Give a code snippet in #C
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 prim... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep 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
... | #Common_Lisp | Common Lisp | (defun sleeprint(n)
(sleep (/ n 10))
(format t "~a~%" n))
(loop for arg in (cdr sb-ext:*posix-argv*) doing
(sb-thread:make-thread (lambda() (sleeprint (parse-integer arg)))))
(loop while (not (null (cdr (sb-thread:list-all-threads))))) | Give a code snippet in #Common_Lisp
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 |
Qu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Write_to_Windows_event_log | Write to Windows event log | Task
Write script status to the Windows Event Log
| #Julia | Julia |
cmd = "eventcreate /T INFORMATION /ID 123 /D \"Rosetta Code Write to Windows event log task example\""
Base.run(`$cmd`)
| Give a code snippet in #Julia
Task
Write script status to the Windows Event Log
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Ranking_methods | Ranking methods |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #PowerShell | PowerShell |
function Get-Ranking
{
[CmdletBinding(DefaultParameterSetName="Standard")]
[OutputType([PSCustomObject])]
Param
(
[Parameter(Mandatory=$true,
ValueFromPipeline=$true,
ValueFromPipelineByPropertyName=$true,
Position=0)]
[string]
... | Give a code snippet in #PowerShell
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 |
Qui... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Literals/String | Literals/String | Task
Show literal specification of characters and strings.
If supported, show how the following work:
verbatim strings (quotes where escape sequences are quoted literally)
here-strings
Also, discuss which quotes expand variables.
Related tasks
Special characters
Here document
Other tasks r... | #TI-89_BASIC | TI-89 BASIC | str = "I'm a string. \"You can quote me\". Name\tJos\u00E9\nLocation\tSF." | Give a code snippet in #TI-89_BASIC
Task
Show literal specification of characters and strings.
If supported, show how the following work:
verbatim strings (quotes where escape sequences are quoted literally)
here-strings
Also, discuss which quotes expand variables.
Related tasks
Special charact... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence:_smallest_number_with_exactly_n_divisors | Sequence: smallest number with exactly n divisors | Calculate the sequence where each term an is the smallest natural number that has exactly n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
Related tasks
Sequence: smallest number greater than previous term with exactly n divisors
Sequence: nth number with exactly... | #F.23 | F# |
// Find Antı-Primes plus. Nigel Galloway: April 9th., 2019
// Increasing the value 14 will increase the number of anti-primes plus found
let fI=primes|>Seq.take 14|>Seq.map bigint|>List.ofSeq
let N=Seq.reduce(*) fI
let fG g=Seq.unfold(fun ((n,i,e) as z)->Some(z,(n+1,i+1,(e*g)))) (1,2,g)
let fE n i=n|>Seq.collect(fun... | Give a code snippet in #F.23
Calculate the sequence where each term an is the smallest natural number that has exactly n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
Related tasks
Sequence: smallest number greater than previous term with exactly n divisors
Seq... | 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... | #TUSCRIPT | TUSCRIPT |
$$ MODE DATA
$$ script=*
/**
* Some comments
* longer comments here that we can parse.
*
* Rahoo
*/
function subroutine() {
a = /* inline comment */ b + c ;
}
/*/ <-- tricky comments */
/**
* Another comment.
*/
function something() {
}
$$ MODE TUSCRIPT
ERROR/STOP C... | Give a code snippet in #TUSCRIPT
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 sho... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Summarize_and_say_sequence | Summarize and say sequence | There are several ways to generate a self-referential sequence. One very common one (the Look-and-say sequence) is to start with a positive integer, then generate the next term by concatenating enumerated groups of adjacent alike digits:
0, 10, 1110, 3110, 132110, 1113122110, 311311222110 ...
The terms generat... | #Aime | Aime | text
next(text s)
{
integer c, e, l;
index v;
data d;
l = ~s;
while (l) {
v[-s[l -= 1]] += 1;
}
for (c, e in v) {
b_form(d, "%d%c", e, -c);
}
return d;
}
integer
depth(text s, integer i, record r)
{
integer d;
d = 0;
r_j_integer(d, r, s);
if ... | Give a code snippet in #Aime
There are several ways to generate a self-referential sequence. One very common one (the Look-and-say sequence) is to start with a positive integer, then generate the next term by concatenating enumerated groups of adjacent alike digits:
0, 10, 1110, 3110, 132110, 1113122110, 31131... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep 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
... | #Ada | Ada | with Ada.Text_IO;
with Ada.Command_Line; use Ada.Command_Line;
procedure SleepSort is
task type PrintTask (num : Integer);
task body PrintTask is begin
delay Duration (num) / 100.0;
Ada.Text_IO.Put(num'Img);
end PrintTask;
type TaskAcc is access PrintTask;
TaskList : array (1 .. Argument_Coun... | Give a code snippet in #Ada
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/B%C3%A9zier_curves/Quadratic | Bitmap/Bézier curves/Quadratic | Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve
(definition on Wikipedia).
| #Tcl | Tcl | Define cubic(p1,p2,p3,segs) = Prgm
Local i,t,u,prev,pt
0 → pt
For i,1,segs+1
(i-1.0)/segs → t © Decimal to avoid slow exact arithetic
(1-t) → u
pt → prev
u^2*p1 + 2*t*u*p2 + t^2*p3 → pt
If i>1 Then
PxlLine floor(prev[1,1]), floor(prev[1,2]), floor(pt[1,1]), floor(pt[1,2])
EndIf
E... | Give a code snippet in #Tcl
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve
(definition on Wikipedia).
| 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 ×... | #Sidef | Sidef | func jacobsthal(n) {
lucasU(1, -2, n)
}
func lucas_jacobsthal(n) {
lucasV(1, -2, n)
}
say "First 30 Jacobsthal numbers:"
say 30.of(jacobsthal)
say "\nFirst 30 Jacobsthal-Lucas numbers:"
say 30.of(lucas_jacobsthal)
say "\nFirst 20 Jacobsthal oblong numbers:"
say 21.of(jacobsthal).cons(2, {|a,b| a * b })
... | Give a code snippet in #Sidef
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/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
≤... | #XQuery | XQuery |
(:
Using the EXPath File Module, which is built into most XQuery processors
by default and thus does not need to get imported. Some processors bind the
namespace automatically, others require explicit declaration.
:)
xquery version "3.1";
declare namespace file = 'http://expath.org/ns/file';
let $in ... | Give a code snippet in #XQuery
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, separat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Euler_method | Euler method | Euler's method numerically approximates solutions of first-order ordinary differential equations (ODEs) with a given initial value. It is an explicit method for solving initial value problems (IVPs), as described in the wikipedia page.
The ODE has to be provided in the following form:
d
y
(
t
)
d
t
=
f... | #11l | 11l | F euler(f, y0, a, b, h)
V t = a
V y = y0
L t <= b
print(‘#2.3 #2.3’.format(t, y))
t += h
y += h * f(t, y)
V newtoncooling = (time, temp) -> -0.07 * (temp - 20)
euler(newtoncooling, 100.0, 0.0, 100.0, 10.0) | Give a code snippet in #11l
Euler's method numerically approximates solutions of first-order ordinary differential equations (ODEs) with a given initial value. It is an explicit method for solving initial value problems (IVPs), as described in the wikipedia page.
The ODE has to be provided in the following form:
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Write_entire_file | Write entire file | Task
(Over)write a file so that it contains a string.
The reverse of Read entire file—for when you want to update or create a file which you would read in its entirety all at once.
| #Elixir | Elixir | File.write("file.txt", string) | Give a code snippet in #Elixir
Task
(Over)write a file so that it contains a string.
The reverse of Read entire file—for when you want to update or create a file which you would read in its entirety all at once.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Polymorphism | Polymorphism | Task
Create two classes Point(x,y) and Circle(x,y,r) with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
| #Ela | Ela | type Point = Point x y
instance Show Point where
show (Point x y) = "Point " ++ (show x) ++ " " ++ (show y)
instance Name Point where
getField nm (Point x y)
| nm == "x" = x
| nm == "y" = y
| else = fail "Undefined name."
isField nm _ = nm == "x" || nm == "y"
pointX = flip Point 0
pointY = Poi... | Give a code snippet in #Ela
Task
Create two classes Point(x,y) and Circle(x,y,r) with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Thiele%27s_interpolation_formula | Thiele's interpolation formula |
This page uses content from Wikipedia. The original article was at Thiele's interpolation 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)
Thiele's interpolation formula is an interpolation ... | #11l | 11l | F thieleInterpolator(x, y)
V ρ = enumerate(y).map((i, yi) -> [yi] * (@y.len - i))
L(i) 0 .< ρ.len - 1
ρ[i][1] = (x[i] - x[i + 1]) / (ρ[i][0] - ρ[i + 1][0])
L(i) 2 .< ρ.len
L(j) 0 .< ρ.len - i
ρ[j][i] = (x[j] - x[j + i]) / (ρ[j][i - 1] - ρ[j + 1][i - 1]) + ρ[j + 1][i - 2]
V ρ0 = ρ[0]
... | Give a code snippet in #11l
This page uses content from Wikipedia. The original article was at Thiele's interpolation 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)
Thiele's interpolation... | 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,... | #Yabasic | Yabasic | dim a(10) // create a numeric array with 11 elements, from 0 to 10
// Indexed at your preference (0 to 9 or 1 to 10)
print arraysize(a(), 1) // this function return the element's higher number of an array
a(7) = 12.3 // access to an element of the array
redim a(20) // alias of 'dim'. Grouth size of array
... | Give a code snippet in #Yabasic
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/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.
| #Lua | Lua | --9x9 sudoku solver in lua
--based on a branch and bound solution
--fields are not tried in plain order
--but in a way to detect dead ends earlier
concat=table.concat
insert=table.insert
constraints = { } --contains a table with 3 constraints for every field
-- a contraint "cons" is a table containing all fields whic... | Give a code snippet in #Lua
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/Animate_a_pendulum | Animate a pendulum |
One good way of making an animation is by simulating a physical system and illustrating the variables in that system using a dynamically changing graphical display.
The classic such physical system is a simple gravity pendulum.
Task
Create a simple physical model of a pendulum and animate it.
| #QB64 | QB64 | 'declare and initialize variables
CONST PI = 3.141592
DIM SHARED Bob_X, Bob_Y, Pivot_X, Pivot_Y, Rod_Length, Rod_Angle, Bob_Angular_Acceleration, Bob_Angular_Velocity, Delta_Time, Drawing_Scale, G AS DOUBLE
DIM SHARED exit_flag AS INTEGER
'set gravity to Earth's by default (in m/s squared)
G = -9.80665
'set the p... | Give a code snippet in #QB64
One good way of making an animation is by simulating a physical system and illustrating the variables in that system using a dynamically changing graphical display.
The classic such physical system is a simple gravity pendulum.
Task
Create a simple physical model of a pendulum and an... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_multiples_of_3_and_5 | Sum multiples of 3 and 5 | Task
The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n.
Show output for n = 1000.
This is is the same as Project Euler problem 1.
Extra credit: do this efficiently for n = 1e20 or higher.
| #PHP | PHP | $max = 1000;
$sum = 0;
for ($i = 1 ; $i < $max ; $i++) {
if (($i % 3 == 0) or ($i % 5 == 0)) {
$sum += $i;
}
}
echo $sum, PHP_EOL;
| Give a code snippet in #PHP
Task
The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n.
Show output for n = 1000.
This is is the same as Project Euler problem 1.
Extra credit: do this efficiently for n = 1e20 or higher.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Repeat | Repeat | Task
Write a procedure which accepts as arguments another procedure and a positive integer.
The latter procedure is executed a number of times equal to the accepted integer.
| #Batch_File | Batch File |
@echo off
:_main
setlocal
call:_func1 _func2 3
pause>nul
exit/b
:_func1
setlocal enabledelayedexpansion
for /l %%i in (1,1,%2) do call:%1
exit /b
:_func2
setlocal
echo _func2 has been executed
exit /b
| Give a code snippet in #Batch_File
Task
Write a procedure which accepts as arguments another procedure and a positive integer.
The latter procedure is executed a number of times equal to the accepted integer.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_largest_left_truncatable_prime_in_a_given_base | Find largest left truncatable prime in a given base | A truncatable prime is one where all non-empty substrings that finish at the end of the number (right-substrings) are also primes when understood as numbers in a particular base. The largest such prime in a given (integer) base is therefore computable, provided the base is larger than 2.
Let's consider what happens in... | #Eiffel | Eiffel |
class
LARGEST_LEFT_TRUNCABLE_PRIME
create
make
feature
make
-- Tests find_prime for different bases.
local
i: INTEGER
decimal: INTEGER_64
do
from
i := 3
until
i = 10
loop
largest := 0
find_prime ("", i)
decimal := convert_to_decimal (largest, i)
io.put_string (i.... | Give a code snippet in #Eiffel
A truncatable prime is one where all non-empty substrings that finish at the end of the number (right-substrings) are also primes when understood as numbers in a particular base. The largest such prime in a given (integer) base is therefore computable, provided the base is larger than 2.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Euler%27s_identity | Euler's identity |
This page uses content from Wikipedia. The original article was at Euler's_identity. 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)
In mathematics, Euler's identity is the equality:
... | #C | C | #include <stdio.h>
#include <math.h>
#include <complex.h>
#include <wchar.h>
#include <locale.h>
int main() {
wchar_t pi = L'\u03c0'; /* Small pi symbol */
wchar_t ae = L'\u2245'; /* Approximately equals symbol */
double complex e = cexp(M_PI * I) + 1.0;
setlocale(LC_CTYPE, "");
printf("e ^ %lci +... | Give a code snippet in #C
This page uses content from Wikipedia. The original article was at Euler's_identity. 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)
In mathematics, Euler's identity is t... | 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 ... | #Clojure | Clojure | (defn get-code [c]
(case c
(\B \F \P \V) 1
(\C \G \J \K
\Q \S \X \Z) 2
(\D \T) 3
\L 4
(\M \N) 5
\R 6
nil)) ;(\A \E \I \O \U \H \W \Y)
(defn soundex [s]
(let [[f & s] (.toUpperCase s)]
(-> (map get-code s)
distinct
(concat , "0000")
(->> (cons f ,)
(remove nil? ,)
... | Give a code snippet in #Clojure
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Letter_frequency | Letter frequency | Task
Open a text file and count the occurrences of each letter.
Some of these programs count all characters (including punctuation),
but some only count letters A to Z.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequen... | #EchoLisp | EchoLisp |
;; bump count when letter added
(define (hash-counter hash key )
;; (set! key (string-downcase key)) - if ignore case wanted
(putprop hash (1+ (or (getprop hash key) 0 )) key))
;; apply to exploded string
;; and sort result
(define (hash-compare a b) ( < (first a) (first b)))
(define (count-letters hash strin... | Give a code snippet in #EchoLisp
Task
Open a text file and count the occurrences of each letter.
Some of these programs count all characters (including punctuation),
but some only count letters A to Z.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (... | 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
| #Huginn | Huginn | from Algorithms import materialize, zip;
main() {
keys = [1, 2, 3];
values = ['a', 'b', 'c'];
hash = materialize( zip( key, values ), lookup );
} | Give a code snippet in #Huginn
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/Benford%27s_law | Benford's law |
This page uses content from Wikipedia. The original article was at Benford's_law. 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)
Benford's law, also called the first-digit law, refers to the freque... | #R | R |
pbenford <- function(d){
return(log10(1+(1/d)))
}
get_lead_digit <- function(number){
return(as.numeric(substr(number,1,1)))
}
fib_iter <- function(n){
first <- 1
second <- 0
for(i in 1:n){
sum <- first + second
first <- second
second <- sum
}
return(sum)
}
fib_sequence <- mapply(fib_i... | Give a code snippet in #R
This page uses content from Wikipedia. The original article was at Benford's_law. 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)
Benford's law, also called the first-digi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Move-to-front_algorithm | Move-to-front algorithm | Given a symbol table of a zero-indexed array of all possible input symbols
this algorithm reversibly transforms a sequence
of input symbols into an array of output numbers (indices).
The transform in many cases acts to give frequently repeated input symbols
lower indices which is useful in some compression algorithms... | #Wren | Wren | import "/fmt" for Fmt
import "/seq" for Lst
var encode = Fn.new { |s|
if (s.isEmpty) return []
var symbols = "abcdefghijklmnopqrstuvwxyz".toList
var result = List.filled(s.count, 0)
var i = 0
for (c in s) {
var index = Lst.indexOf(symbols, c)
if (index == -1) Fiber.abort("%(s) con... | Give a code snippet in #Wren
Given a symbol table of a zero-indexed array of all possible input symbols
this algorithm reversibly transforms a sequence
of input symbols into an array of output numbers (indices).
The transform in many cases acts to give frequently repeated input symbols
lower indices which is useful ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #VBA | VBA | Option Explicit
Sub Main()
Dim s As String, FF As Integer
'read a file line by line
FF = FreeFile
Open "C:\Users\" & Environ("username") & "\Desktop\input.txt" For Input As #FF
While Not EOF(FF)
Line Input #FF, s
Debug.Print s
Wend
Close #FF
'read a file
FF = FreeFile
Open "C:\Users\" & Environ("username"... | Give a code snippet in #VBA
File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file int... | 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.
| #Go | Go | package main
import (
"bufio"
"io"
"os"
)
func main() {
r := bufio.NewReader(os.Stdin)
w := bufio.NewWriter(os.Stdout)
for {
b, err := r.ReadByte()
if err == io.EOF {
return
}
w.WriteByte(b)
w.Flush()
}
} | Give a code snippet in #Go
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/Josephus_problem | Josephus problem | Josephus problem is a math puzzle with a grim description:
n
{\displaystyle n}
prisoners are standing on a circle, sequentially numbered from
0
{\displaystyle 0}
to
n
−
1
{\displaystyle n-1}
.
An executioner walks along the circle, starting from prisoner
0
{\displaystyle 0}
,
removing eve... | #Rust | Rust | const N: usize = 41;
const K: usize = 3;
const M: usize = 3;
const POSITION: usize = 5;
fn main() {
let mut prisoners: Vec<usize> = Vec::new();
let mut executed: Vec<usize> = Vec::new();
for pos in 0..N {
prisoners.push(pos);
}
let mut to_kill: usize = 0;
let mut len: usize = prisone... | Give a code snippet in #Rust
Josephus problem is a math puzzle with a grim description:
n
{\displaystyle n}
prisoners are standing on a circle, sequentially numbered from
0
{\displaystyle 0}
to
n
−
1
{\displaystyle n-1}
.
An executioner walks along the circle, starting from prisoner
0
{\d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Happy_numbers | Happy numbers | From Wikipedia, the free encyclopedia:
A happy number is defined by the following process:
Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in a cycle which does not inclu... | #APL | APL | ∇ HappyNumbers arg;⎕IO;∆roof;∆first;bin;iroof
[1] ⍝0: Happy number
[2] ⍝1: http://rosettacode.org/wiki/Happy_numbers
[3] ⎕IO←1 ⍝ Index origin
[4] ∆roof ∆first←2↑arg,10 ⍝
[5]
[6] bin←{
[7] ⍺←⍬ ⍝ Default left arg
[8] ⍵=1:... | Give a code snippet in #APL
From Wikipedia, the free encyclopedia:
A happy number is defined by the following process:
Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_definition | Function definition | A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract from showing how functions are ... | #Racket | Racket | (define (multiply a b) (* a b)) | Give a code snippet in #Racket
A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/While | Loops/While | Task
Start an integer value at 1024.
Loop while it is greater than zero.
Print the value (with a newline) and divide it by two each time through the loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For... | #Trith | Trith | 1024 [dup print 2 / floor] [dup 0 >] while drop | Give a code snippet in #Trith
Task
Start an integer value at 1024.
Loop while it is greater than zero.
Print the value (with a newline) and divide it by two each time through the loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downwar... | 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 ... | #Julia | Julia | arr(s) = [c for c in s]
alldup(a) = filter(x -> length(x) > 1, [findall(x -> x == a[i], a) for i in 1:length(a)])
firstduplicate(s) = (a = arr(s); d = alldup(a); isempty(d) ? nothing : first(d))
function testfunction(strings)
println("String | Length | All Unique | First Duplicate | Pos... | Give a code snippet in #Julia
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 leng... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sleep | Sleep | Task
Write a program that does the following in this order:
Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
Print "Sleeping..."
Sleep the main thread for the given amount of time.
... | #JavaScript | JavaScript | <script>
setTimeout(function () {
document.write('Awake!')
}, prompt("Number of milliseconds to sleep"));
document.write('Sleeping... ');
</script> | Give a code snippet in #JavaScript
Task
Write a program that does the following in this order:
Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
Print "Sleeping..."
Sleep the main t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation | Horner's rule for polynomial evaluation | A fast scheme for evaluating a polynomial such as:
−
19
+
7
x
−
4
x
2
+
6
x
3
{\displaystyle -19+7x-4x^{2}+6x^{3}\,}
when
x
=
3
{\displaystyle x=3\;}
.
is to arrange the computation as follows:
(
(
(
(
0
)
x
+
6
)
x
+
(
−
4
)
)
x
+
7
)
x
+
(
−
19
)
{\displaystyle ((((0)x+6)x+(-4))x... | #Java | Java | import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class Horner {
public static void main(String[] args){
List<Double> coeffs = new ArrayList<Double>();
coeffs.add(-19.0);
coeffs.add(7.0);
coeffs.add(-4.0);
coeffs.add(6.0);
Syste... | Give a code snippet in #Java
A fast scheme for evaluating a polynomial such as:
−
19
+
7
x
−
4
x
2
+
6
x
3
{\displaystyle -19+7x-4x^{2}+6x^{3}\,}
when
x
=
3
{\displaystyle x=3\;}
.
is to arrange the computation as follows:
(
(
(
(
0
)
x
+
6
)
x
+
(
−
4
)
)
x
+
7
)
x
+
(
−
19
)
{\d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_whitespace_from_a_string/Top_and_tail | Strip whitespace from a string/Top and tail | Task
Demonstrate how to strip leading and trailing whitespace from a string.
The solution should demonstrate how to achieve the following three results:
String with leading whitespace removed
String with trailing whitespace removed
String with both leading and trailing whitespace removed
For the purposes of thi... | #Erlang | Erlang | % Implemented by Arjun Sunel
1> string:strip(" Hello World! ", left). %remove leading whitespaces
"Hello World! "
2> string:strip(" Hello World! ", right). % remove trailing whitespaces
" Hello World!"
3> string:strip(" Hello World! ", both). % remove both leading and trailing whitespace
"Hello Wor... | Give a code snippet in #Erlang
Task
Demonstrate how to strip leading and trailing whitespace from a string.
The solution should demonstrate how to achieve the following three results:
String with leading whitespace removed
String with trailing whitespace removed
String with both leading and trailing whitespace r... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Calculating_the_value_of_e | Calculating the value of e | Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| #Ada | Ada | with Ada.Text_IO; use Ada.Text_IO;
with Ada.Long_Float_Text_IO; use Ada.Long_Float_Text_IO;
procedure Euler is
Epsilon : constant := 1.0E-15;
Fact : Long_Integer := 1;
E : Long_Float := 2.0;
E0 : Long_Float := 0.0;
N : Long_Integer := 2;
begin
loop
E0... | Give a code snippet in #Ada
Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Pick_random_element | Pick random element | Demonstrate how to pick a random element from a list.
| #GAP | GAP | a := [2, 9, 4, 7, 5, 3];
Random(a); | Give a code snippet in #GAP
Demonstrate how to pick a random element from a list.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Fractran | Fractran | FRACTRAN is a Turing-complete esoteric programming language invented by the mathematician John Horton Conway.
A FRACTRAN program is an ordered list of positive fractions
P
=
(
f
1
,
f
2
,
…
,
f
m
)
{\displaystyle P=(f_{1},f_{2},\ldots ,f_{m})}
, together with an initial positive integer input
n
... | #Nim | Nim |
import strutils
import bignum
const PrimeProg = "17/91 78/85 19/51 23/38 29/33 77/29 95/23 77/19 1/17 11/13 13/11 15/14 15/2 55/1"
iterator values(prog: openArray[Rat]; init: Natural): Int =
## Run the program "prog" with initial value "init" and yield the values.
var n = newInt(init)
var next: Rat
while ... | Give a code snippet in #Nim
FRACTRAN is a Turing-complete esoteric programming language invented by the mathematician John Horton Conway.
A FRACTRAN program is an ordered list of positive fractions
P
=
(
f
1
,
f
2
,
…
,
f
m
)
{\displaystyle P=(f_{1},f_{2},\ldots ,f_{m})}
, together with an initial ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Nested | Loops/Nested | Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over
[
1
,
…
,
20
]
{\displaystyle [1,\ldots ,20]}
.
The loops iterate rows and columns of the array printing the elements until the value
20
{\displaystyle 20}
is met.
Specifically, this task als... | #OCaml | OCaml | $ ocaml
# Random.self_init();;
- : unit = ()
# let m = Array.make_matrix 10 10 0 ;;
val m : int array array =
[|[|0; 0; 0; 0; 0; 0; 0; 0; 0; 0|]; [|0; 0; 0; 0; 0; 0; 0; 0; 0; 0|];
[|0; 0; 0; 0; 0; 0; 0; 0; 0; 0|]; [|0; 0; 0; 0; 0; 0; 0; 0; 0; 0|];
[|0; 0; 0; 0; 0; 0; 0; 0; 0; 0|]; [|0; 0; 0; 0; 0; 0; 0; 0... | Give a code snippet in #OCaml
Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over
[
1
,
…
,
20
]
{\displaystyle [1,\ldots ,20]}
.
The loops iterate rows and columns of the array printing the elements until the value
20
{\displaystyle 20}
is me... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Execute_Computer/Zero | Execute Computer/Zero | Execute Computer/Zero is an implementation of Computer/zero Assembly.
Other implementations of Computer/zero Assembly.
Task
Create a Computer/zero Assembly emulator. You may consider this webpage as a reference implementation. Output the results of the sample programs "2+2" and "7*8" found there.
The virtual machi... | #Wren | Wren | var NOP = 0
var LDA = 1
var STA = 2
var ADD = 3
var SUB = 4
var BRZ = 5
var JMP = 6
var STP = 7
var ops = {"NOP": NOP, "LDA": LDA, "STA": STA, "ADD": ADD,
"SUB": SUB, "BRZ": BRZ, "JMP": JMP, "STP": STP}
var load = Fn.new { |prog|
var mem = List.filled(32, 0)
var lines = prog.trimEnd().split("\n")... | Give a code snippet in #Wren
Execute Computer/Zero is an implementation of Computer/zero Assembly.
Other implementations of Computer/zero Assembly.
Task
Create a Computer/zero Assembly emulator. You may consider this webpage as a reference implementation. Output the results of the sample programs "2+2" and "7*8" foun... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Levenshtein_distance | Levenshtein distance |
This page uses content from Wikipedia. The original article was at Levenshtein distance. 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)
In information theory and computer science, the Levenshtein ... | #Liberty_BASIC | Liberty BASIC | 'Levenshtein Distance translated by Brandon Parker
'08/19/10
'from http://www.merriampark.com/ld.htm#VB
'No credit was given to the Visual Basic Author on the site :-(
Print LevenshteinDistance("kitten", "sitting")
End
'Get the minum of three values
Function Minimum(a, b, c)
Minimum = Min(a, Min(b, c))
End Func... | Give a code snippet in #Liberty_BASIC
This page uses content from Wikipedia. The original article was at Levenshtein distance. 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)
In information theory... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Foreach | Loops/Foreach | Loop through and print each element in a collection in order.
Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for... | #Rust | Rust | let collection = vec![1,2,3,4,5];
for elem in collection {
println!("{}", elem);
} | Give a code snippet in #Rust
Loop through and print each element in a collection in order.
Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Polynomial_long_division | Polynomial long division |
This page uses content from Wikipedia. The original article was at Polynomial long division. 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)
In algebra, polynomial long division is an algorithm for d... | #Python | Python | # -*- coding: utf-8 -*-
from itertools import izip
def degree(poly):
while poly and poly[-1] == 0:
poly.pop() # normalize
return len(poly)-1
def poly_div(N, D):
dD = degree(D)
dN = degree(N)
if dD < 0: raise ZeroDivisionError
if dN >= dD:
q = [0] * dN
while dN >= ... | Give a code snippet in #Python
This page uses content from Wikipedia. The original article was at Polynomial long division. 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)
In algebra, polynomial lon... | christopher/rosetta-code | |
http://rosettacode.org/wiki/General_FizzBuzz | General FizzBuzz | Task
Write a generalized version of FizzBuzz that works for any list of factors, along with their words.
This is basically a "fizzbuzz" implementation where the user supplies the parameters.
The user will enter the max number, then they will enter the factors to be calculated along with the corresponding word to be ... | #PHP | PHP | <?php
$max = 20;
$factor = array(3 => 'Fizz', 5 => 'Buzz', 7 => 'Jazz');
for ($i = 1 ; $i <= $max ; $i++) {
$matched = false;
foreach ($factor AS $number => $word) {
if ($i % $number == 0) {
echo $word;
$matched = true;
}
}
echo ($matched ? '' : $i), PHP_EOL;
... | Give a code snippet in #PHP
Task
Write a generalized version of FizzBuzz that works for any list of factors, along with their words.
This is basically a "fizzbuzz" implementation where the user supplies the parameters.
The user will enter the max number, then they will enter the factors to be calculated along with ... | 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... | #Groovy | Groovy | def haversine(lat1, lon1, lat2, lon2) {
def R = 6372.8
// In kilometers
def dLat = Math.toRadians(lat2 - lat1)
def dLon = Math.toRadians(lon2 - lon1)
lat1 = Math.toRadians(lat1)
lat2 = Math.toRadians(lat2)
def a = Math.sin(dLat / 2) * Math.sin(dLat / 2) + Math.sin(dLon / 2) * Math.sin(dLon / 2) * Math.c... | Give a code snippet in #Groovy
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 equ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Infinity | Infinity | Task
Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity. Otherwise, return the largest possible po... | #Smalltalk | Smalltalk | st> FloatD infinity
Inf
st> 1.0 / 0.0
Inf
| Give a code snippet in #Smalltalk
Task
Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity. Otherw... | christopher/rosetta-code | |
http://rosettacode.org/wiki/100_doors | 100 doors | There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #6, ...), and toggle it.
The third... | #Visual_Basic | Visual Basic |
Public Sub Doors100()
' the state of a door is represented by the data type boolean (false = door closed, true = door opened)
Dim doorstate(1 To 100) As Boolean ' the doorstate()-array is initialized by VB with value 'false'
Dim i As Long, j As Long
For i = 1 To 100
For j = i To 100 Step i
d... | Give a code snippet in #Visual_Basic
There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4,... | 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... | #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Dim As Integer n
Do
Input "Enter size of matrix "; n
Loop Until n > 0
Dim zigzag(1 To n, 1 To n) As Integer '' all zero by default
' enter the numbers 0 to (n^2 - 1) in the matrix's anti-diagonals
zigzag(1, 1) = 0
If n > 1 Then
Dim As Integer row = 0, col = 3
Dim As Boolean down = true,... | Give a code snippet in #FreeBASIC
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... | 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... | #Kotlin | Kotlin | // version 1.0.6
fun main(args: Array<String>) {
for (i in 0 .. 2) {
for (j in 0 .. 2) {
if (i + j == 2) continue
if (i + j == 3) break
println(i + j)
}
}
println()
if (args.isNotEmpty()) throw IllegalArgumentException("No command line arguments shou... | Give a code snippet in #Kotlin
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
... | #Ruby | Ruby | 1.upto(100) do |n|
print "Fizz" if a = (n % 3).zero?
print "Buzz" if b = (n % 5).zero?
print n unless (a || b)
puts
end | Give a code snippet in #Ruby
Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz ... | 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
≤... | #Oberon-2 | Oberon-2 | MODULE ab;
IMPORT In, Out;
VAR A, B : INTEGER;
BEGIN
In.Int (A);
In.Int (B);
Out.Int (A + B, 8);
Out.Ln
END ab. | Give a code snippet in #Oberon-2
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, separ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Execute_a_system_command | Execute a system command | Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| #Octave | Octave | system("ls"); | Give a code snippet in #Octave
Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Classes | Classes | In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T.
The first type T from the class T sometimes is called the root type of the class.
A class of types itself, a... | #Oz | Oz | declare
class Something
feat
name %% immutable, public attribute (called a "feature")
attr
count %% mutable, private attribute
%% public method which is used as an initializer
meth init(N)
self.name = N
count := 0
end
%% public method
meth increas... | Give a code snippet in #Oz
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T.
The first type T from the class T sometimes is called the root type of the class.... | 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 ... | #Klingphix | Klingphix | :sq_mul
%c %i
( ) !c
len [
!i
$i get rot $i get rot * $c swap 0 put !c
] for
$c
;
:sq_sum
0 swap
len [
get rot + swap
] for
swap
;
( 1 3 -5 ) ( 4 -2 -1 )
sq_mul
sq_sum
pstack
" " input | Give a code snippet in #Klingphix
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Conway%27s_Game_of_Life | Conway's Game of Life | The Game of Life is a cellular automaton devised by the British mathematician John Horton Conway in 1970. It is the best-known example of a cellular automaton.
Conway's game of life is described here:
A cell C is represented by a 1 when alive, or 0 when dead, in an m-by-m (or m×m) sq... | #J | J | pad=: 0,0,~0,.0,.~]
life=: (3 3 (+/ e. 3+0,4&{)@,;._3 ])@pad
NB. the above could also be a one-line solution:
life=: (3 3 (+/ e. 3+0,4&{)@,;._3 ])@(0,0,~0,.0,.~])
| Give a code snippet in #J
The Game of Life is a cellular automaton devised by the British mathematician John Horton Conway in 1970. It is the best-known example of a cellular automaton.
Conway's game of life is described here:
A cell C is represented by a 1 when alive, or 0 when dead, in ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Day_of_the_week | Day of the week | A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January).
Task
In what years between 2008 and 2121 will the 25th of ... | #GAP | GAP | Filtered([2008 .. 2121], y -> WeekDay([25, 12, y]) = "Sun");
# [ 2011, 2016, 2022, 2033, 2039, 2044, 2050, 2061, 2067, 2072, 2078, 2089, 2095, 2101, 2107, 2112, 2118 ]
# A possible implementation of WeekDayAlt
days := ["Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"];;
WeekDayAlt := function(args)
local d, m, ... | Give a code snippet in #GAP
A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January).
Task
In what years between 20... | christopher/rosetta-code |
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