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/Jump_anywhere | Jump anywhere | Imperative programs
conditional structures
loops
local jumps
This task is to demonstrate a local jump and a global jump and the various other types of jumps that the language supports.
For the purpose of this task, the jumps need not be used for a single purpose and you have the freedom to use these jumps for different... | #QB64 | QB64 |
' Jumps in QB64 are inherited by Qbasic/ QuickBasic/ GWBasic
' here a GOTO demo of loops FOR-NEXT and WHILE-WEND
Dim S As String, Q As Integer
Randomize Timer
0:
Locate 1, 1: Print "jump demostration"
Print "Press J to jump to FOR NEXT emulator or"
Print "L to jump to WHILE WEND emulator or"
Print "Q for quitting"... | Give a code snippet in #QB64
Imperative programs
conditional structures
loops
local jumps
This task is to demonstrate a local jump and a global jump and the various other types of jumps that the language supports.
For the purpose of this task, the jumps need not be used for a single purpose and you have the freedom to... | christopher/rosetta-code | |
http://rosettacode.org/wiki/AKS_test_for_primes | AKS test for primes | The AKS algorithm for testing whether a number is prime is a polynomial-time algorithm based on an elementary theorem about Pascal triangles.
The theorem on which the test is based can be stated as follows:
a number
p
{\displaystyle p}
is prime if and only if all the coefficients of the polynomial ... | #PureBasic | PureBasic | EnableExplicit
Define vzr.b = -1, vzc.b = ~vzr, nMAX.i = 10, n.i , k.i
Procedure coeff(nRow.i, Array pd.i(2))
Define n.i, k.i
For n=1 To nRow
For k=0 To n
If k=0 Or k=n : pd(n,k)=1 : Continue : EndIf
pd(n,k)=pd(n-1,k-1)+pd(n-1,k)
Next
Next
EndProcedure
Procedure.b isPrime(n.i, Array pd.i(2... | Give a code snippet in #PureBasic
The AKS algorithm for testing whether a number is prime is a polynomial-time algorithm based on an elementary theorem about Pascal triangles.
The theorem on which the test is based can be stated as follows:
a number
p
{\displaystyle p}
is prime if and only if all ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Towers_of_Hanoi | Towers of Hanoi | Task
Solve the Towers of Hanoi problem with recursion.
| #Agena | Agena | move := proc(n::number, src::number, dst::number, via::number) is
if n > 0 then
move(n - 1, src, via, dst)
print(src & ' to ' & dst)
move(n - 1, via, dst, src)
fi
end
move(4, 1, 2, 3) | Give a code snippet in #Agena
Task
Solve the Towers of Hanoi problem with recursion.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Euler%27s_sum_of_powers_conjecture | Euler's sum of powers conjecture | There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth power,
except for the trivial case... | #Pascal | Pascal | program Pot5Test;
{$IFDEF FPC} {$MODE DELPHI}{$ELSE]{$APPTYPE CONSOLE}{$ENDIF}
type
tTest = double;//UInt64;{ On linux 32Bit double is faster than Uint64 }
var
Pot5 : array[0..255] of tTest;
res,tmpSum : tTest;
x0,x1,x2,x3, y : NativeUint;//= Uint32 or 64 depending on OS xx-Bit
i : byte;
BEGIN
For i := 1 ... | Give a code snippet in #Pascal
There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth power,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Combinations | Combinations | Task
Given non-negative integers m and n, generate all size m combinations of the integers from 0 (zero) to n-1 in sorted order (each combination is sorted and the entire table is sorted).
Example
3 comb 5 is:
0 1 2
0 1 3
0 1 4
0 2 3
0 2 4
0 3 4
1 2 3
1 2 4
1 3 4
2 3 4
... | #PARI.2FGP | PARI/GP | Crv ( k, v, d ) = {
if( d == k,
print ( vecextract( v , "2..-2" ) )
,
for( i = v[ d + 1 ] + 1, #v,
v[ d + 2 ] = i;
Crv( k, v, d + 1 ) ));
}
combRV( n, k ) = Crv ( k, vector( n, X, X-1), 0 ); | Give a code snippet in #PARI.2FGP
Task
Given non-negative integers m and n, generate all size m combinations of the integers from 0 (zero) to n-1 in sorted order (each combination is sorted and the entire table is sorted).
Example
3 comb 5 is:
0 1 2
0 1 3
0 1 4
0 2 3
0... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_concatenation | Array concatenation | Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| #M2000_Interpreter | M2000 Interpreter |
a=(1,2,3,4,5)
b=Cons(a, (6,7,8),a)
Print b
1 2 3 4 5 6 7 8 1 2 3 4 5
| Give a code snippet in #M2000_Interpreter
Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Simple_moving_average | Averages/Simple moving average | Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving average is a method for computing an avera... | #Rust | Rust | struct SimpleMovingAverage {
period: usize,
numbers: Vec<usize>
}
impl SimpleMovingAverage {
fn new(p: usize) -> SimpleMovingAverage {
SimpleMovingAverage {
period: p,
numbers: Vec::new()
}
}
fn add_number(&mut self, number: usize) -> f64 {
self.nu... | Give a code snippet in #Rust
Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving average is a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Date_manipulation | Date manipulation | Task
Given the date string "March 7 2009 7:30pm EST",
output the time 12 hours later in any human-readable format.
As extra credit, display the resulting time in a time zone different from your own.
| #Groovy | Groovy | import org.joda.time.*
import java.text.*
def dateString = 'March 7 2009 7:30pm EST'
def sdf = new SimpleDateFormat('MMMM d yyyy h:mma zzz')
DateTime dt = new DateTime(sdf.parse(dateString))
println (dt)
println (dt.plusHours(12))
println (dt.plusHours(12).withZone(DateTimeZone.UTC)) | Give a code snippet in #Groovy
Task
Given the date string "March 7 2009 7:30pm EST",
output the time 12 hours later in any human-readable format.
As extra credit, display the resulting time in a time zone different from your own.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Command-line_arguments | Command-line arguments | Command-line arguments is part of Short Circuit's Console Program Basics selection.
Scripted main
See also Program name.
For parsing command line arguments intelligently, see Parsing command-line arguments.
Example command line:
myprogram -c "alpha beta" -h "gamma"
| #PicoLisp | PicoLisp | #!/usr/bin/picolisp /usr/lib/picolisp/lib.l
(de c ()
(prinl "Got 'c': " (opt)) )
(de h ()
(prinl "Got 'h': " (opt)) )
(load T)
(bye) | Give a code snippet in #PicoLisp
Command-line arguments is part of Short Circuit's Console Program Basics selection.
Scripted main
See also Program name.
For parsing command line arguments intelligently, see Parsing command-line arguments.
Example command line:
myprogram -c "alpha beta" -h "gamma"
| christopher/rosetta-code | |
http://rosettacode.org/wiki/File_size_distribution | File size distribution | Task
Beginning from the current directory, or optionally from a directory specified as a command-line argument, determine how many files there are of various sizes in a directory hierarchy.
My suggestion is to sort by logarithmn of file size, since a few bytes here or there, or even a factor of two or three, may no... | #Rust | Rust |
use std::error::Error;
use std::marker::PhantomData;
use std::path::{Path, PathBuf};
use std::{env, fmt, io, time};
use walkdir::{DirEntry, WalkDir};
fn main() -> Result<(), Box<dyn Error>> {
let start = time::Instant::now();
let args: Vec<String> = env::args().collect();
let root = parse_path(&args).... | Give a code snippet in #Rust
Task
Beginning from the current directory, or optionally from a directory specified as a command-line argument, determine how many files there are of various sizes in a directory hierarchy.
My suggestion is to sort by logarithmn of file size, since a few bytes here or there, or even a ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/XML/Output | XML/Output | Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks.
All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks> element.
As an example, calling ... | #Lua | Lua | require("LuaXML")
function addNode(parent, nodeName, key, value, content)
local node = xml.new(nodeName)
table.insert(node, content)
parent:append(node)[key] = value
end
root = xml.new("CharacterRemarks")
addNode(root, "Character", "name", "April", "Bubbly: I'm > Tam and <= Emily")
addNode(root, "Charac... | Give a code snippet in #Lua
Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks.
All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks> elem... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Elliptic_Curve_Digital_Signature_Algorithm | Elliptic Curve Digital Signature Algorithm | Elliptic curves.
An elliptic curve E over ℤp (p ≥ 5) is defined by an equation of the form
y^2 = x^3 + ax + b, where a, b ∈ ℤp and the discriminant ≢ 0 (mod p),
together with a special point 𝒪 called the point at infinity.
The set E(ℤp) consists of all points (x, y), with x, y ∈ ℤp,
which satisfy the above defining eq... | #Wren | Wren | import "/dynamic" for Struct
import "/big" for BigInt
import "/fmt" for Fmt
import "/math" for Boolean
import "random" for Random
var rand = Random.new()
// rational ec point: x and y are BigInts
var Epnt = Struct.create("Epnt", ["x", "y"])
// elliptic curve parameters: N is a BigInt, G is an Epnt, rest are integ... | Give a code snippet in #Wren
Elliptic curves.
An elliptic curve E over ℤp (p ≥ 5) is defined by an equation of the form
y^2 = x^3 + ax + b, where a, b ∈ ℤp and the discriminant ≢ 0 (mod p),
together with a special point 𝒪 called the point at infinity.
The set E(ℤp) consists of all points (x, y), with x, y ∈ ℤp,
which... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_three_variables | Sort three variables |
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
... | #Little_Man_Computer | Little Man Computer |
// Little Man Computer
// Sort x, y, z, in ascending order
// Based on a sorting network:
// if x > z then swap( x, z)
// if x > y then swap( x, y)
// if y > z then swap( y, z)
// with the addition that if the 2nd swap is executed
// then the 3rd comparison is not needed.
// Read numbers x, y, z, and display ... | Give a code snippet in #Little_Man_Computer
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 s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_file_character_by_character/UTF8 | Read a file character by character/UTF8 | Task
Read a file one character at a time, as opposed to reading the entire file at once.
The solution may be implemented as a procedure, which returns the next character in the file on each consecutive call (returning EOF when the end of the file is reached).
The procedure should support the reading of files contain... | #Racket | Racket |
#lang racket
; This file contains utf-8 charachters: λ, α, γ ...
(for ([c (in-port read-char (open-input-file "read-file.rkt"))])
(display c))
| Give a code snippet in #Racket
Task
Read a file one character at a time, as opposed to reading the entire file at once.
The solution may be implemented as a procedure, which returns the next character in the file on each consecutive call (returning EOF when the end of the file is reached).
The procedure should supp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bernoulli_numbers | Bernoulli numbers | Bernoulli numbers are used in some series expansions of several functions (trigonometric, hyperbolic, gamma, etc.), and are extremely important in number theory and analysis.
Note that there are two definitions of Bernoulli numbers; this task will be using the modern usage (as per The National Institute of S... | #Visual_Basic_.NET | Visual Basic .NET | ' Bernoulli numbers - vb.net - 06/03/2017
Imports System.Numerics 'BigInteger
Module Bernoulli_numbers
Function gcd_BigInt(ByVal x As BigInteger, ByVal y As BigInteger) As BigInteger
Dim y2 As BigInteger
x = BigInteger.Abs(x)
Do
y2 = BigInteger.Remainder(x, y)
x =... | Give a code snippet in #Visual_Basic_.NET
Bernoulli numbers are used in some series expansions of several functions (trigonometric, hyperbolic, gamma, etc.), and are extremely important in number theory and analysis.
Note that there are two definitions of Bernoulli numbers; this task will be using the modern us... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roots_of_a_quadratic_function | Roots of a quadratic function | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Write a program to find the roots of a quadratic equation, i.e., solve the equation
a
x
2
+
b
x
+
c
=
0
{\displaystyle ax^{2}+bx+c=0}
.
Your program must correctly handle n... | #Java | Java | public class QuadraticRoots {
private static class Complex {
double re, im;
public Complex(double re, double im) {
this.re = re;
this.im = im;
}
@Override
public boolean equals(Object obj) {
if (obj == this) {return true;}
i... | Give a code snippet in #Java
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Write a program to find the roots of a quadratic equation, i.e., solve the equation
a
x
2
+
b
x
+
c
=
0
{\displaystyle ax^{2}+bx+c=0}
.
Your p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Special_variables | Special variables | Special variables have a predefined meaning within a computer programming language.
Task
List the special variables used within the language.
| #D | D | func Integer.Double() {
this + this
}
print(8.Double()) | Give a code snippet in #D
Special variables have a predefined meaning within a computer programming language.
Task
List the special variables used within the language.
| 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... | #PL.2FI | PL/I | *process or(!) source attributes xref;
joseph: Proc Options(main);
/* REXX **************************************************************
* 15.11.2012 Walter Pachl - my own solution
* 16.11.2012 Walter Pachl generalized n prisoners + w killing distance
* and s=number of survivors
* 03.05.2... | Give a code snippet in #PL.2FI
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
{... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Leap_year | Leap year | Task
Determine whether a given year is a leap year in the Gregorian calendar.
See also
Leap year (wiki)
| #Julia | Julia | isleap(yr::Integer) = yr % 4 == 0 && (yr < 1582 || yr % 400 == 0 || yr % 100 != 0)
@assert all(isleap, [2400, 2012, 2000, 1600, 1500, 1400])
@assert !any(isleap, [2100, 2014, 1900, 1800, 1700, 1499]) | Give a code snippet in #Julia
Task
Determine whether a given year is a leap year in the Gregorian calendar.
See also
Leap year (wiki)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
Other tasks re... | #Clipper | Clipper | Replicate( "Ha", 5 ) | Give a code snippet in #Clipper
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Standard_error | Hello world/Standard error | Hello world/Standard error is part of Short Circuit's Console Program Basics selection.
A common practice in computing is to send error messages
to a different output stream than normal text console messages.
The normal messages print to what is called "standard output" or "standard out".
The error messages print to ... | #C | C | #include <stdio.h>
int main()
{
fprintf(stderr, "Goodbye, ");
fputs("World!\n", stderr);
return 0;
} | Give a code snippet in #C
Hello world/Standard error is part of Short Circuit's Console Program Basics selection.
A common practice in computing is to send error messages
to a different output stream than normal text console messages.
The normal messages print to what is called "standard output" or "standard out".
T... | 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... | #11l | 11l | F zigzag(n)
F compare(xy)
V (x, y) = xy
R (x + y, I (x + y) % 2 {-y} E y)
V xs = 0 .< n
R Dict(enumerate(sorted((multiloop(xs, xs, (x, y) -> (x, y))), key' compare)), (n, index) -> (index, n))
F printzz(myarray)
V n = Int(myarray.len ^ 0.5 + 0.5)
V xs = 0 .< n
print((xs.map(y -> @xs.map(... | Give a code snippet in #11l
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 encod... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #J | J | variable=: ''
0=#variable
1
0<#variable
0 | Give a code snippet in #J
Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Unbias_a_random_generator | Unbias a random generator |
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to create a function/method/sub... | #Rust | Rust | #![feature(inclusive_range_syntax)]
extern crate rand;
use rand::Rng;
fn rand_n<R: Rng>(rng: &mut R, n: u32) -> usize {
rng.gen_weighted_bool(n) as usize // maps `false` to 0 and `true` to 1
}
fn unbiased<R: Rng>(rng: &mut R, n: u32) -> usize {
let mut bit = rand_n(rng, n);
while bit == rand_n(rng, ... | Give a code snippet in #Rust
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Retrieve_and_search_chat_history | Retrieve and search chat history | Task
Summary: Find and print the mentions of a given string in the recent chat logs from a chatroom. Only use your programming language's standard library.
Details:
The Tcl Chatroom is an online chatroom. Its conversations are logged. It's useful to know if someone has mentioned you or your project in the chatroom r... | #Go | Go | package main
import (
"fmt"
"io/ioutil"
"log"
"net/http"
"os"
"strings"
"time"
)
func get(url string) (res string, err error) {
resp, err := http.Get(url)
if err != nil {
return "", err
}
buf, err := ioutil.ReadAll(resp.Body)
if err != nil {
return "", err
}
return string(buf), nil
}
func grep(n... | Give a code snippet in #Go
Task
Summary: Find and print the mentions of a given string in the recent chat logs from a chatroom. Only use your programming language's standard library.
Details:
The Tcl Chatroom is an online chatroom. Its conversations are logged. It's useful to know if someone has mentioned you or yo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ordered_partitions | Ordered partitions | In this task we want to find the ordered partitions into fixed-size blocks.
This task is related to Combinations in that it has to do with discrete mathematics and moreover a helper function to compute combinations is (probably) needed to solve this task.
p
a
r
t
i
t
i
o
n
s
(
a
r
g
1
,
a
r
g
2
,
... | #Nim | Nim | import algorithm, math, sequtils, strutils
type Partition = seq[seq[int]]
func isIncreasing(s: seq[int]): bool =
## Return true if the sequence is sorted in increasing order.
var prev = 0
for val in s:
if prev >= val: return false
prev = val
result = true
iterator partitions(lengths: varargs[i... | Give a code snippet in #Nim
In this task we want to find the ordered partitions into fixed-size blocks.
This task is related to Combinations in that it has to do with discrete mathematics and moreover a helper function to compute combinations is (probably) needed to solve this task.
p
a
r
t
i
t
i
o
n
s
(
a
r
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Damm_algorithm | Damm algorithm | The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors.
The algorithm is named after H. Michael Damm.
Task
Verify the checksum, stored as last digit of an input.
| #MAD | MAD | NORMAL MODE IS INTEGER
R VERIFY DAMM CHECKSUM OF NUMBER
INTERNAL FUNCTION(CKNUM)
VECTOR VALUES DAMMIT =
0 0,3,1,7,5,9,8,6,4,2
1 , 7,0,9,2,1,5,4,8,6,3
2 , 4,2,0,6,8,7,1,3,5,9
3 , 1,7,5,0,9,8,3,4,2,6
4... | Give a code snippet in #MAD
The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors.
The algorithm is named after H. Michael Damm.
Task
Verify the checksum, stored as last digit of an input.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Super-d_numbers | Super-d numbers | A super-d number is a positive, decimal (base ten) integer n such that d × nd has at least d consecutive digits d where
2 ≤ d ≤ 9
For instance, 753 is a super-3 number because 3 × 7533 = 1280873331.
Super-d numbers are also shown on MathWorld™ as super-d or super-d.
Task
Write a... | #D | D | import std.bigint;
import std.conv;
import std.stdio;
import std.string;
void main() {
auto rd = ["22", "333", "4444", "55555", "666666", "7777777", "88888888", "999999999"];
BigInt one = 1;
BigInt nine = 9;
for (int ii = 2; ii <= 9; ii++) {
writefln("First 10 super-%d numbers:", ii);
... | Give a code snippet in #D
A super-d number is a positive, decimal (base ten) integer n such that d × nd has at least d consecutive digits d where
2 ≤ d ≤ 9
For instance, 753 is a super-3 number because 3 × 7533 = 1280873331.
Super-d numbers are also shown on MathWorld™ as super-d or ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Integer_comparison | Integer comparison |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Modula-2 | Modula-2 | MODULE IntCompare;
IMPORT InOut;
VAR
A, B: INTEGER;
BEGIN
InOut.ReadInt(A);
InOut.ReadInt(B);
InOut.WriteInt(A, 1);
IF A < B THEN
InOut.WriteString(' is less than ')
ELSIF A = B THEN
InOut.WriteString(' is equal to ')
ELSE
InOut.WriteString(' is greater than ')
END;
InOut.WriteInt(... | Give a code snippet in #Modula-2
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operatio... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Harshad_or_Niven_series | Harshad or Niven series | The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits.
For example, 42 is a Harshad number as 42 is divisible by (4 + 2) without remainder.
Assume that the series is defined as the numbers in increasing order.
Task
The task is to create a function/method/... | #PicoLisp | PicoLisp |
#if niven number, return it.
(de niven (N)
(if (=0 (% N (apply + (getN N)))) N) )
#function which creates a list of numbers from input
(de getN (N)
(mapcar format (chop N)) )
#This function generates niven number list
(de nivGen (R N)
(extract niven (range R N)) )
#print 1st 20 niven numbers and 1st ni... | Give a code snippet in #PicoLisp
The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits.
For example, 42 is a Harshad number as 42 is divisible by (4 + 2) without remainder.
Assume that the series is defined as the numbers in increasing order.
Task
The ta... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fixed_length_records | Fixed length records | Fixed length read/write
Before terminals, computers commonly used punch card readers or paper tape input.
A common format before these devices were superseded by terminal technology was based on the Hollerith code, Hollerith code.
These input devices handled 80 columns per card and had a limited character set, encod... | #Phix | Phix | without js -- file i/o
constant sample_text = """
Line 1...1.........2.........3.........4.........5.........6.........7.........8
Line 2
Line 3
Line 4
Line 6
Line 7
Indented line 8............................................................
Line 9 ... | Give a code snippet in #Phix
Fixed length read/write
Before terminals, computers commonly used punch card readers or paper tape input.
A common format before these devices were superseded by terminal technology was based on the Hollerith code, Hollerith code.
These input devices handled 80 columns per card and had ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Quaternion_type | Quaternion type | Quaternions are an extension of the idea of complex numbers.
A complex number has a real and complex part, sometimes written as a + bi,
where a and b stand for real numbers, and i stands for the square root of minus 1.
An example of a complex number might be -3 + 2i,
wher... | #jq | jq | def Quaternion(q0;q1;q2;q3): { "q0": q0, "q1": q1, "q2": q2, "q3": q3, "type": "Quaternion" };
# promotion of a real number to a quaternion
def Quaternion(r): if (r|type) == "number" then Quaternion(r;0;0;0) else r end;
# thoroughly recursive pretty-print
def pp:
def signage: if . >= 0 then "+ \(.)" else "- \... | Give a code snippet in #jq
Quaternions are an extension of the idea of complex numbers.
A complex number has a real and complex part, sometimes written as a + bi,
where a and b stand for real numbers, and i stands for the square root of minus 1.
An example of a complex number mig... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Split_a_character_string_based_on_change_of_character | Split a character string based on change of character |
Task
Split a (character) string into comma (plus a blank) delimited
strings based on a change of character (left to right).
Show the output here (use the 1st example below).
Blanks should be treated as any other character (except
they are problematic to display clearly). The same applies
to commas.
Fo... | #C.23 | C# | using System;
using System.Linq;
using System.Collections.Generic;
public class Program
{
string s = @"gHHH5YY++///\";
Console.WriteLine(s.RunLengthSplit().Delimit(", "));
}
public static class Extensions
{
public static IEnumerable<string> RunLengthSplit(this string source) {
using (var enumera... | Give a code snippet in #C.23
Task
Split a (character) string into comma (plus a blank) delimited
strings based on a change of character (left to right).
Show the output here (use the 1st example below).
Blanks should be treated as any other character (except
they are problematic to display clearly). The... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_comparison | String comparison |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Factor | Factor | USING: ascii math.order sorting.human ;
IN: scratchpad "foo" "bar" = . ! compare for equality
f
IN: scratchpad "foo" "bar" = not . ! compare for inequality
t
IN: scratchpad "foo" "bar" before? . ! lexically ordered before?
f
IN: scratchpad "foo" "bar" after? . ! lexically ordered after?
t
IN: scratchpad "Foo" "foo" <... | Give a code snippet in #Factor
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #OCaml | OCaml | let get g x y =
try g.(x).(y)
with _ -> 0
let neighbourhood g x y =
(get g (x-1) (y-1)) +
(get g (x-1) (y )) +
(get g (x-1) (y+1)) +
(get g (x ) (y-1)) +
(get g (x ) (y+1)) +
(get g (x+1) (y-1)) +
(get g (x+1) (y )) +
(get g (x+1) (y+1))
let next_cell g x y =
let n = neighbourhood g x y i... | Give a code snippet in #OCaml
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/Dutch_national_flag_problem | Dutch national flag problem |
The Dutch national flag is composed of three coloured bands in the order:
red (top)
then white, and
lastly blue (at the bottom).
The problem posed by Edsger Dijkstra is:
Given a number of red, blue and white balls in random order, arrange them in the order of the colours in the Dutch national fla... | #Ceylon | Ceylon | import ceylon.random {
DefaultRandom
}
abstract class Colour(name, ordinal) of red | white | blue satisfies Comparable<Colour> {
shared String name;
shared Integer ordinal;
string => name;
compare(Colour other) => this.ordinal <=> other.ordinal;
}
object red extends Colour("red", 0) {}
object white extends ... | Give a code snippet in #Ceylon
The Dutch national flag is composed of three coloured bands in the order:
red (top)
then white, and
lastly blue (at the bottom).
The problem posed by Edsger Dijkstra is:
Given a number of red, blue and white balls in random order, arrange them in the order of the c... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_length | String length | Task
Find the character and byte length of a string.
This means encodings like UTF-8 need to be handled properly, as there is not necessarily a one-to-one relationship between bytes and characters.
By character, we mean an individual Unicode code point, not a user-visible grapheme containing combining characters.
F... | #Wren | Wren | System.print("møøse".bytes.count)
System.print("𝔘𝔫𝔦𝔠𝔬𝔡𝔢".bytes.count)
System.print("J̲o̲s̲é̲".bytes.count) | Give a code snippet in #Wren
Task
Find the character and byte length of a string.
This means encodings like UTF-8 need to be handled properly, as there is not necessarily a one-to-one relationship between bytes and characters.
By character, we mean an individual Unicode code point, not a user-visible grapheme conta... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Shell_sort | Sorting algorithms/Shell 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
... | #PureBasic | PureBasic | #STEP=2.2
Procedure Shell_sort(Array A(1))
Protected l=ArraySize(A()), increment=Int(l/#STEP)
Protected i, j, temp
While increment
For i= increment To l
j=i
temp=A(i)
While j>=increment And A(j-increment)>temp
A(j)=A(j-increment)
j-increment
Wend
A(j)=temp
N... | Give a code snippet in #PureBasic
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bioinformatics/base_count | Bioinformatics/base count | Given this string representing ordered DNA bases:
CGTAAAAAATTACAACGTCCTTTGGCTATCTCTTAAACTCCTGCTAAATG
CTCGTGCTTTCCAATTATGTAAGCGTTCCGAGACGGGGTGGTCGATTCTG
AGGACAAAGGTCAAGATGGAGCGCATCGAACGCAATAAGGATCATTTGAT
GGGACGTTTCGTCGACAAAGTCTTGTTTCGAGAGTAACGGCTACCGTCTT
CGATTCTGCTTATAACACTATGTTCTTATGAAATGGATGTTCTGAGTTGG
TCAGTCCCAATGTG... | #Forth | Forth |
( Gforth 0.7.3 )
: dnacode s" CGTAAAAAATTACAACGTCCTTTGGCTATCTCTTAAACTCCTGCTAAATGCTCGTGCTTTCCAATTATGTAAGCGTTCCGAGACGGGGTGGTCGATTCTGAGGACAAAGGTCAAGATGGAGCGCATCGAACGCAATAAGGATCATTTGATGGGACGTTTCGTCGACAAAGTCTTGTTTCGAGAGTAACGGCTACCGTCTTCGATTCTGCTTATAACACTATGTTCTTATGAAATGGATGTTCTGAGTTGGTCAGTCCCAATGTGCGGGGTTTCTTTTAGTACGTCG... | Give a code snippet in #Forth
Given this string representing ordered DNA bases:
CGTAAAAAATTACAACGTCCTTTGGCTATCTCTTAAACTCCTGCTAAATG
CTCGTGCTTTCCAATTATGTAAGCGTTCCGAGACGGGGTGGTCGATTCTG
AGGACAAAGGTCAAGATGGAGCGCATCGAACGCAATAAGGATCATTTGAT
GGGACGTTTCGTCGACAAAGTCTTGTTTCGAGAGTAACGGCTACCGTCTT
CGATTCTGCTTATAACACTATGTTCTTATGAAAT... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dynamic_variable_names | Dynamic variable names | Task
Create a variable with a user-defined name.
The variable name should not be written in the program text, but should be taken from the user dynamically.
See also
Eval in environment is a similar task.
| #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Type DynamicVariable
As String name
As String value
End Type
Function FindVariableIndex(a() as DynamicVariable, v as String, nElements As Integer) As Integer
v = LCase(Trim(v))
For i As Integer = 1 To nElements
If a(i).name = v Then Return i
Next
Return 0
End Function
Dim As Int... | Give a code snippet in #FreeBASIC
Task
Create a variable with a user-defined name.
The variable name should not be written in the program text, but should be taken from the user dynamically.
See also
Eval in environment is a similar task.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/File_modification_time | File modification time | Task
Get and set the modification time of a file.
| #C | C | #include <sys/stat.h>
#include <stdio.h>
#include <time.h>
#include <utime.h>
const char *filename = "input.txt";
int main() {
struct stat foo;
time_t mtime;
struct utimbuf new_times;
if (stat(filename, &foo) < 0) {
perror(filename);
return 1;
}
mtime = foo.st_mtime; /* seconds since the epoch... | Give a code snippet in #C
Task
Get and set the modification time of a file.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Compile-time_calculation | Compile-time calculation | Some programming languages allow calculation of values at compile time.
Task
Calculate 10! (ten factorial) at compile time.
Print the result when the program is run.
Discuss what limitations apply to compile-time calculations in your language.
| #Haskell | Haskell | module Factorial where
import Language.Haskell.TH.Syntax
fact n = product [1..n]
factQ :: Integer -> Q Exp
factQ = lift . fact | Give a code snippet in #Haskell
Some programming languages allow calculation of values at compile time.
Task
Calculate 10! (ten factorial) at compile time.
Print the result when the program is run.
Discuss what limitations apply to compile-time calculations in your language.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Rename_a_file | Rename a file | Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has the rights to do so.
(In unix-type s... | #Run_BASIC | Run BASIC | a$ = shell$("RENAME input.txt output.txt")
a$ = shell$("RENAME docs mydocs")
a$ = shell$("RENAME \input.txt \output.txt")
a$ = shell$("RENAME \docs \mydocs") | Give a code snippet in #Run_BASIC
Task
Rename:
a file called input.txt into output.txt and
a directory called docs into mydocs.
This should be done twice:
once "here", i.e. in the current working directory and once in the filesystem root.
It can be assumed that the user has th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Pancake_sort | Sorting algorithms/Pancake 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
... | #Quackery | Quackery | [ split reverse join ] is flip ( [ n --> [ )
[ 0 swap behead swap
witheach
[ 2dup > iff
[ nip nip
i^ 1+ swap ]
else drop ]
drop ] is smallest ( [ --> n )
[ dup size times
[ dup i^ split nip
smallest i^ + flip
i^ flip ] ] i... | Give a code snippet in #Quackery
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Maple | Maple |
with(LinearAlgebra):
ReducedRowEchelonForm(<<1,2,-2>|<2,3,0>|<-1,-1,-3>|<-4,-11,22>>);
| Give a code snippet in #Maple
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 convenien... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Leap_year | Leap year | Task
Determine whether a given year is a leap year in the Gregorian calendar.
See also
Leap year (wiki)
| #Modula-2 | Modula-2 | MODULE LeapYear;
FROM FormatString IMPORT FormatString;
FROM Terminal IMPORT WriteString,ReadChar;
PROCEDURE IsLeapYear(year : INTEGER) : BOOLEAN;
BEGIN
IF year MOD 100 = 0 THEN
RETURN year MOD 400 = 0;
END;
RETURN year MOD 4 = 0
END IsLeapYear;
PROCEDURE Print(year : INTEGER);
VAR
buf : ARR... | Give a code snippet in #Modula-2
Task
Determine whether a given year is a leap year in the Gregorian calendar.
See also
Leap year (wiki)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #PowerShell | PowerShell |
&{}
| Give a code snippet in #PowerShell
Task
Create the simplest possible program that is still considered "correct."
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Check_output_device_is_a_terminal | Check output device is a terminal | Task
Demonstrate how to check whether the output device is a terminal or not.
Related task
Check input device is a terminal
| #UNIX_Shell | UNIX Shell | #!/bin/sh
if [ -t 1 ]
then
echo "Output is a terminal"
else
echo "Output is NOT a terminal" >/dev/tty
fi | Give a code snippet in #UNIX_Shell
Task
Demonstrate how to check whether the output device is a terminal or not.
Related task
Check input device is a terminal
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Anti-primes | Anti-primes | The anti-primes
(or highly composite numbers, sequence A002182 in the OEIS)
are the natural numbers with more factors than any smaller than itself.
Task
Generate and show here, the first twenty anti-primes.
Related tasks
Factors of an integer
Sieve of Eratosthenes
| #AppleScript | AppleScript | on factorCount(n)
set counter to 0
set sqrt to n ^ 0.5
set limit to sqrt div 1
if (limit = sqrt) then
set counter to counter + 1
set limit to limit - 1
end if
repeat with i from limit to 1 by -1
if (n mod i is 0) then set counter to counter + 2
end repeat
return... | Give a code snippet in #AppleScript
The anti-primes
(or highly composite numbers, sequence A002182 in the OEIS)
are the natural numbers with more factors than any smaller than itself.
Task
Generate and show here, the first twenty anti-primes.
Related tasks
Factors of an integer
Sieve of Eratosthenes
| 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... | #Factor | Factor | USING: io kernel math.ranges prettyprint random sequences ;
10 [ 20 [ 20 [1,b] random ] replicate ] replicate ! make a table of random values
[ [ dup pprint bl 20 = ] find nl drop ] find 2drop ! print values until 20 is found | Give a code snippet in #Factor
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 m... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_matching | String matching |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #GML | GML | #define charMatch
{
first = "qwertyuiop";
// Determining if the first string starts with second string
second = "qwerty";
if (string_pos(second, first) > 0) {
show_message("'" + first + "' starts with '" + second + "'");
} else {
show_message("'" + first + "' does not start with '... | Give a code snippet in #GML
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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,... | #Modula-2 | Modula-2 | VAR staticArray: ARRAY [1..10] OF INTEGER; | Give a code snippet in #Modula-2
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 re... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_and_product_of_an_array | Sum and product of an array | Task
Compute the sum and product of an array of integers.
| #F.C5.8Drmul.C3.A6 | Fōrmulæ | Public Sub Main()
Dim iList As Integer[] = [1, 2, 3, 4, 5]
Dim iSum, iCount As Integer
Dim iPrd As Integer = 1
For iCount = 0 To iList.Max
iSum += iList[iCount]
iPrd *= iList[iCount]
Next
Print "The Sum =\t" & iSum
Print "The Product =\t" & iPrd
End | Give a code snippet in #F.C5.8Drmul.C3.A6
Task
Compute the sum and product of an array of integers.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Concurrent_computing | Concurrent computing | Task
Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order.
Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
| #PowerShell | PowerShell | $Strings = "Enjoy","Rosetta","Code"
$SB = {param($String)Write-Output $String}
foreach($String in $Strings) {
Start-Job -ScriptBlock $SB -ArgumentList $String | Out-Null
}
Get-Job | Wait-Job | Receive-Job
Get-Job | Remove-Job | Give a code snippet in #PowerShell
Task
Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order.
Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in y... | 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
| #dc | dc | 1000 sn [ n = number of iterations ]sx
2574k [ precision to use during computation ]sx
1 d se sf [ set e and f to 1 ]sx
0 si [ set i to 0 ]sx
[ [ p = begin ]sx
lf li 1 + d si * sf [ f = f*(++i) ]sx
le 1 lf / + se [... | Give a code snippet in #dc
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/Simulate_input/Mouse | Simulate input/Mouse | #FreeBASIC | FreeBASIC | #include "fbgfx.bi"
#define rect 4
Windowtitle "Mouse events"
Screen 19,32
Dim Shared As Integer xres, yres
Screeninfo xres, yres
Type box
As Single x, y, z
As String caption
As Uinteger textcol, boxcol
End Type
Dim Shared As box label(rect,1)
Dim Shared As box button(rect,1)
Dim Shared As Boolean fla... | Give a code snippet in #FreeBASIC
| christopher/rosetta-code | ||
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #LotusScript | LotusScript | Sub Click()
'a few declarations as example
Dim s as New NotesSession ' declaring a New NotesSession actually returns the current, active NotesSession
Dim i as Integer ' i = 0
Dim s as String ' s= ""
Dim v as Variant ' v is nothing
Dim l as Long ' l = 0
Dim doc as NotesDocument 'doc is EMTPY
'...
End Sub
| Give a code snippet in #LotusScript
Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Ackermann_function | Ackermann function | The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
n
+
1
if
m
=
0
A
(
m
... | #Eiffel | Eiffel |
note
description: "Example of Ackerman function"
synopsis: "[
The EIS link below (in Eiffel Studio) will launch in either an in-IDE browser or
and external browser (your choice). The protocol informs Eiffel Studio about what
program to use to open the `src' reference, which can be URI, PDF, or DOC. See
seco... | Give a code snippet in #Eiffel
The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/First-class_functions | First-class functions | A language has first-class functions if it can do each of the following without recursively invoking a compiler or interpreter or otherwise metaprogramming:
Create new functions from preexisting functions at run-time
Store functions in collections
Use functions as arguments to other functions
Use functions as retu... | #Bracmat | Bracmat | ( (sqrt=.!arg^1/2)
& (log=.e\L!arg)
& (A=x2d (=.!arg^2) log (=.!arg*pi))
& ( B
= d2x sqrt (=.e^!arg) (=.!arg*pi^-1)
)
& ( compose
= f g
. !arg:(?f.?g)
& '(.($f)$(($g)$!arg))
)
& whl
' ( !A:%?F ?A
& !B:%?G ?B
& out$((compose$(!F.!G))$3210)
)
) | Give a code snippet in #Bracmat
A language has first-class functions if it can do each of the following without recursively invoking a compiler or interpreter or otherwise metaprogramming:
Create new functions from preexisting functions at run-time
Store functions in collections
Use functions as arguments to other... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number/With_feedback | Guess the number/With feedback | Task
Write a game (computer program) that follows the following rules:
The computer chooses a number between given set limits.
The player is asked for repeated guesses until the the target number is guessed correctly
At each guess, the computer responds with whether the guess is:
higher than the target,
equal to... | #Locomotive_Basic | Locomotive Basic | 10 CLS:RANDOMIZE TIME
20 PRINT "Please specify lower and upper limits":guess=0
30 INPUT " (must be positive integers) :", first, last
40 IF first<1 OR last<1 THEN 20
50 num=INT(RND*(last-first+1)+first)
60 WHILE num<>guess
70 INPUT "Your guess? ", guess
80 IF guess<num THEN PRINT "too small!"
90 IF guess>num THEN PRIN... | Give a code snippet in #Locomotive_Basic
Task
Write a game (computer program) that follows the following rules:
The computer chooses a number between given set limits.
The player is asked for repeated guesses until the the target number is guessed correctly
At each guess, the computer responds with whether the gu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitwise_operations | Bitwise operations |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Kotlin | Kotlin | /* for symmetry with Kotlin's other binary bitwise operators
we wrap Java's 'rotate' methods as infix functions */
infix fun Int.rol(distance: Int): Int = Integer.rotateLeft(this, distance)
infix fun Int.ror(distance: Int): Int = Integer.rotateRight(this, distance)
fun main(args: Array<String>) {
// inferred... | Give a code snippet in #Kotlin
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Swift_2 | Swift | struct RecursiveFunc<F> {
let o : RecursiveFunc<F> -> F
}
func Y<A, B>(f: (A -> B) -> A -> B) -> A -> B {
let r = RecursiveFunc<A -> B> { w in f { w.o(w)($0) } }
return r.o(r)
}
let fac = Y { (f: Int -> Int) in
{ $0 <= 1 ? 1 : $0 * f($0-1) }
}
let fib = Y { (f: Int -> Int) in
{ $0 <= 2 ? 1 : f($0-1)+f($0-... | Give a code snippet in #Swift_2
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Chinese_zodiac | Chinese zodiac | Traditionally, the Chinese have counted years using two simultaneous cycles, one of length 10 (the "celestial stems") and one of length 12 (the "terrestrial branches"); the combination results in a repeating 60-year pattern. Mapping the branches to twelve traditional animal deities results in the well-known "Chinese zo... | #uBasic.2F4tH | uBasic/4tH | dim @y(2) ' yin or yang
dim @e(5) ' the elements
dim @a(12) ' the animals
Push Dup("yang"), Dup("yin") ' fill Ying/Yang table
For i = 1 to 0 step -1 : @y(i) = Pop() : Next i
' fill El... | Give a code snippet in #uBasic.2F4tH
Traditionally, the Chinese have counted years using two simultaneous cycles, one of length 10 (the "celestial stems") and one of length 12 (the "terrestrial branches"); the combination results in a repeating 60-year pattern. Mapping the branches to twelve traditional animal deities... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_an_object_at_a_given_address | Create an object at a given address |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #C.2B.2B | C++ | #include <string>
#include <iostream>
int main()
{
// Allocate enough memory to hold an instance of std::string
char* data = new char[sizeof(std::string)];
// use placement new to construct a std::string in the memory we allocated previously
std::string* stringPtr = new (data) std::string("ABCD");
... | Give a code snippet in #C.2B.2B
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operation... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Magic_squares_of_odd_order | Magic squares of odd order | A magic square is an NxN square matrix whose numbers (usually integers) consist of consecutive numbers arranged so that the sum of each row and column, and both long (main) diagonals are equal to the same sum (which is called the magic number or magic constant).
The numbers are usually (but not always) t... | #Nim | Nim | import strutils
proc magic(n: int) =
let length = len($(n * n))
for row in 1 .. n:
for col in 1 .. n:
let cell = (n * ((row + col - 1 + n div 2) mod n) +
((row + 2 * col - 2) mod n) + 1)
stdout.write ($cell).align(length), ' '
echo ""
echo "\nAll sum to magic number ", (n *... | Give a code snippet in #Nim
A magic square is an NxN square matrix whose numbers (usually integers) consist of consecutive numbers arranged so that the sum of each row and column, and both long (main) diagonals are equal to the same sum (which is called the magic number or magic constant).
The numbers a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pascal%27s_triangle/Puzzle | Pascal's triangle/Puzzle | This puzzle involves a Pascals Triangle, also known as a Pyramid of Numbers.
[ 151]
[ ][ ]
[40][ ][ ]
[ ][ ][ ][ ]
[ X][11][ Y][ 4][ Z]
Each brick of the pyramid is the sum of the two bricks situated below it.
Of the three missing numbers at the base of the pyramid,
the... | #PARI.2FGP | PARI/GP |
Pascals_triangle_puzzle(topvalue=151,leftsidevalue=40,bottomvalue1=11,bottomvalue2=4) = {
y=(topvalue-(4*(bottomvalue1+bottomvalue2)))/7;
x=leftsidevalue-(y+2*bottomvalue1);
z=y-x;
print(x","y","z); }
| Give a code snippet in #PARI.2FGP
This puzzle involves a Pascals Triangle, also known as a Pyramid of Numbers.
[ 151]
[ ][ ]
[40][ ][ ]
[ ][ ][ ][ ]
[ X][11][ Y][ 4][ Z]
Each brick of the pyramid is the sum of the two bricks situated below it.
Of the three missing numb... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Bubble_sort | Sorting algorithms/Bubble sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Dyalect | Dyalect | func bubbleSort(list) {
var done = false
while !done {
done = true
for i in 1..(list.Length()-1) {
if list[i - 1] > list[i] {
var x = list[i]
list[i] = list[i - 1]
list[i - 1] = x
done = false
}
}
... | Give a code snippet in #Dyalect
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Power_set | Power set | A set is a collection (container) of certain values,
without any particular order, and no repeated values.
It corresponds with a finite set in mathematics.
A set can be implemented as an associative array (partial mapping)
in which the value of each key-value pair is ignored.
Given a set S, the power set (or pow... | #Icon_and_Unicon | Icon and Unicon |
procedure power_set (s)
result := set ()
if *s = 0
then insert (result, set ()) # empty set
else {
head := set(?s) # take a random element
# and find powerset of remaining part of set
tail_pset := power_set (x -- head)
result ++:= tail_pset # add powerset of remainder to results
... | Give a code snippet in #Icon_and_Unicon
A set is a collection (container) of certain values,
without any particular order, and no repeated values.
It corresponds with a finite set in mathematics.
A set can be implemented as an associative array (partial mapping)
in which the value of each key-value pair is ignor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Extend_your_language | Extend your language | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua... | #ATS | ATS | (* Languages with pattern matching ALREADY HAVE THIS! *)
fn
func (pred1 : bool, pred2 : bool) : void =
case+ (pred1, pred2) of
| (true, true) => println! ("(true, true)")
| (true, false) => println! ("(true, false)")
| (false, true) => println! ("(false, true)")
| (false, false) => println! ("(false, false)... | Give a code snippet in #ATS
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. b... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Consecutive_primes_with_ascending_or_descending_differences | Consecutive primes with ascending or descending differences | Task
Find and display here on this page, the longest sequence of consecutive prime numbers where the differences between the primes are strictly ascending.
Do the same for sequences of primes where the differences are strictly descending.
In both cases, show the sequence for primes < 1,000,000.
If there... | #ALGOL_68 | ALGOL 68 | BEGIN # find sequences of primes where the gaps between the elements #
# are strictly ascending/descending #
# reurns a list of primes up to n #
PROC prime list = ( INT n )[]INT:
BEGIN
# sieve the primes to n #
INT no = 0, yes = 1;
[ ... | Give a code snippet in #ALGOL_68
Task
Find and display here on this page, the longest sequence of consecutive prime numbers where the differences between the primes are strictly ascending.
Do the same for sequences of primes where the differences are strictly descending.
In both cases, show the sequence for p... | 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 ... | #SPARK | SPARK | with Spark_IO;
--# inherit Spark_IO;
--# main_program;
procedure Dot_Product_Main
--# global in out Spark_IO.Outputs;
--# derives Spark_IO.Outputs from *;
is
Limit : constant := 1000;
type V_Elem is range -Limit .. Limit;
V_Size : constant := 100;
type V_Index is range 1 .. V_Size;
type Vector is array(V... | Give a code snippet in #SPARK
Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Substitution_cipher | Substitution cipher | Substitution Cipher Implementation - File Encryption/Decryption
Task
Encrypt a input/source file by replacing every upper/lower case alphabets of the source file with another predetermined upper/lower case alphabets or symbols and save it into another output/encrypted file and then again convert that output/encrypt... | #Wren | Wren | var key = "]kYV}(!7P$n5_0i R:?jOWtF/=-pe'AD&@r6\%ZXs\"v*N[#wSl9zq2^+g;LoB`aGh{3.HIu4fbK)mU8|dMET><,Qc\\C1yxJ"
var encode = Fn.new { |s|
var res = ""
for (c in s) res = res + key[c.bytes[0] - 32]
return res
}
var decode = Fn.new { |s|
var res = ""
for (c in s) res = res + String.fromByte(key.inde... | Give a code snippet in #Wren
Substitution Cipher Implementation - File Encryption/Decryption
Task
Encrypt a input/source file by replacing every upper/lower case alphabets of the source file with another predetermined upper/lower case alphabets or symbols and save it into another output/encrypted file and then aga... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Middle_three_digits | Middle three digits | Task
Write a function/procedure/subroutine that is called with an integer value and returns the middle three digits of the integer if possible or a clear indication of an error if this is not possible.
Note: The order of the middle digits should be preserved.
Your function should be tested with the following values;... | #Ring | Ring |
n = 1234567
middle(n)
func middle nr
mnr = floor(len(string(nr))/2)
lennr = len(string(nr))
if lennr = 3 see "" + nr + nl
but lennr < 3 see "Number must have at least three digits"
but lennr%2=0 see "Number must have an odd number of digits"
else cnr = substr(string(nr),mnr,3) see cnr ... | Give a code snippet in #Ring
Task
Write a function/procedure/subroutine that is called with an integer value and returns the middle three digits of the integer if possible or a clear indication of an error if this is not possible.
Note: The order of the middle digits should be preserved.
Your function should be tes... | christopher/rosetta-code | |
http://rosettacode.org/wiki/UTF-8_encode_and_decode | UTF-8 encode and decode | As described in UTF-8 and in Wikipedia, UTF-8 is a popular encoding of (multi-byte) Unicode code-points into eight-bit octets.
The goal of this task is to write a encoder that takes a unicode code-point (an integer representing a unicode character) and returns a sequence of 1-4 bytes representing that character in the... | #Lua | Lua |
-- Accept an integer representing a codepoint.
-- Return the values of the individual octets.
function encode (codepoint)
local codepoint_str = utf8.char(codepoint)
local result = {}
for i = 1, #codepoint_str do
result[#result + 1] = string.unpack("B", codepoint_str, i)
end
return table.unpack(resul... | Give a code snippet in #Lua
As described in UTF-8 and in Wikipedia, UTF-8 is a popular encoding of (multi-byte) Unicode code-points into eight-bit octets.
The goal of this task is to write a encoder that takes a unicode code-point (an integer representing a unicode character) and returns a sequence of 1-4 bytes repre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Window_creation/X11 | Window creation/X11 | Task
Create a simple X11 application, using an X11 protocol library such as Xlib or XCB, that draws a box and "Hello World" in a window.
Implementations of this task should avoid using a toolkit as much as possible.
| #TXR | TXR | /* window_creation_x11.wren */
var KeyPressMask = 1 << 0
var ExposureMask = 1 << 15
var KeyPress = 2
var Expose = 12
foreign class XGC {
construct default(display, screenNumber) {}
}
foreign class XEvent {
construct new() {}
foreign eventType
}
foreign class XDisplay {
construct open... | Give a code snippet in #TXR
Task
Create a simple X11 application, using an X11 protocol library such as Xlib or XCB, that draws a box and "Hello World" in a window.
Implementations of this task should avoid using a toolkit as much as possible.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Last_letter-first_letter | Last letter-first letter | A certain children's game involves starting with a word in a particular category. Each participant in turn says a word, but that word must begin with the final letter of the previous word. Once a word has been given, it cannot be repeated. If an opponent cannot give a word in the category, they fall out of the ga... | #Scala | Scala | object LastLetterFirstLetterNaive extends App {
def solve(names: Set[String]) = {
def extend(solutions: List[List[String]]): List[List[String]] = {
val more = solutions.flatMap{solution =>
val lastLetter = solution.head takeRight 1
(names -- solution).filter(_.take(1) equalsIgnoreCase lastLe... | Give a code snippet in #Scala
A certain children's game involves starting with a word in a particular category. Each participant in turn says a word, but that word must begin with the final letter of the previous word. Once a word has been given, it cannot be repeated. If an opponent cannot give a word in the ca... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #F.23 | F# | //val inline factorial :
// ^a -> ^a
// when ^a : (static member get_One : -> ^a) and
// ^a : (static member ( + ) : ^a * ^a -> ^a) and
// ^a : (static member ( * ) : ^a * ^a -> ^a)
let inline factorial n = Seq.reduce (*) [ LanguagePrimitives.GenericOne .. n ] | Give a code snippet in #F.23
Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a nu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Look-and-say_sequence | Look-and-say sequence | The Look and say sequence is a recursively defined sequence of numbers studied most notably by John Conway.
The look-and-say sequence is also known as the Morris Number Sequence, after cryptographer Robert Morris, and the puzzle What is the next number in the sequence 1, 11, 21, 1211, 11122... | #ERRE | ERRE |
PROGRAM LOOK
PROCEDURE LOOK_AND_SAY(N$->N$)
LOCAL I%,J%,C$,O$
I%=1
REPEAT
C$=MID$(N$,I%,1)
J%=I%+1
WHILE MID$(N$,J%,1)=C$ DO
J%+=1
END WHILE
O$+=MID$(STR$(J%-I%),2)+C$
I%=J%
UNTIL I%>LEN(N$)
N$=O$
END PROCEDURE
BEGIN
NUM... | Give a code snippet in #ERRE
The Look and say sequence is a recursively defined sequence of numbers studied most notably by John Conway.
The look-and-say sequence is also known as the Morris Number Sequence, after cryptographer Robert Morris, and the puzzle What is the next number in the sequence ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Zero_to_the_zero_power | Zero to the zero power | Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0**0 or 0^0 at compile time, ... | #NewLISP | NewLISP | (pow 0 0) | Give a code snippet in #NewLISP
Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0**0 o... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tau_function | Tau function | Given a positive integer, count the number of its positive divisors.
Task
Show the result for the first 100 positive integers.
Related task
Tau number
| #AArch64_Assembly | AArch64 Assembly |
/* ARM assembly AARCH64 Raspberry PI 3B or android 64 bits */
/* program taufunction64.s */
/*******************************************/
/* Constantes file */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly*/
.include ".... | Give a code snippet in #AArch64_Assembly
Given a positive integer, count the number of its positive divisors.
Task
Show the result for the first 100 positive integers.
Related task
Tau number
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Roman_numerals/Decode | Roman numerals/Decode | Task
Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer.
You don't need to validate the form of the Roman numeral.
Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately,
starting with the leftmost decima... | #XQuery | XQuery |
xquery version "3.1";
declare function local:decode-roman-numeral($roman-numeral as xs:string) {
$roman-numeral
=> upper-case()
=> for-each(
function($roman-numeral-uppercase) {
analyze-string($roman-numeral-uppercase, ".")/fn:match
! map { "M": 1000, "D": 500, "C": 10... | Give a code snippet in #XQuery
Task
Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer.
You don't need to validate the form of the Roman numeral.
Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately,
s... | 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 ... | #Julia | Julia | function levendist(s::AbstractString, t::AbstractString)
ls, lt = length.((s, t))
ls == 0 && return lt
lt == 0 && return ls
s₁, t₁ = s[2:end], t[2:end]
ld₁ = levendist(s₁, t₁)
s[1] == t[1] ? ld₁ : 1 + min(ld₁, levendist(s, t₁), levendist(s₁, t))
end
@show levendist("kitten", "sitting") # 3
@... | Give a code snippet in #Julia
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 com... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Square_but_not_cube | Square but not cube | Task
Show the first 30 positive integers which are squares but not cubes of such integers.
Optionally, show also the first 3 positive integers which are both squares and cubes, and mark them as such.
| #C | C | #include <stdio.h>
#include <math.h>
int main() {
int n = 1, count = 0, sq, cr;
for ( ; count < 30; ++n) {
sq = n * n;
cr = (int)cbrt((double)sq);
if (cr * cr * cr != sq) {
count++;
printf("%d\n", sq);
}
else {
printf("%d is square an... | Give a code snippet in #C
Task
Show the first 30 positive integers which are squares but not cubes of such integers.
Optionally, show also the first 3 positive integers which are both squares and cubes, and mark them as such.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Palindrome_detection | Palindrome detection | A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibly as a wrapper to the first) which ... | #Potion | Potion | # The readable recursive version
palindrome_i = (s, b, e):
if (e <= b): true.
elsif (s ord(b) != s ord(e)): false.
else: palindrome_i(s, b+1, e-1).
.
palindrome = (s):
palindrome_i(s, 0, s length - 1).
palindrome(argv(1)) | Give a code snippet in #Potion
A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibly a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Lucas-Lehmer_test | Lucas-Lehmer test | Lucas-Lehmer Test:
for
p
{\displaystyle p}
an odd prime, the Mersenne number
2
p
−
1
{\displaystyle 2^{p}-1}
is prime if and only if
2
p
−
1
{\displaystyle 2^{p}-1}
divides
S
(
p
−
1
)
{\displaystyle S(p-1)}
where
S
(
n
+
1
)
=
(
S
(
n
)
)
2
−
2
{\displaystyle S(n+1)=(... | #langur | langur | val .isPrime = f .i == 2 or
.i > 2 and not any f(.x) .i div .x, pseries 2 to .i ^/ 2
val .isMersennePrime = f(.p) {
if .p == 2: return true
if not .isPrime(.p): return false
val .mp = 2 ^ .p - 1
for[.s=4] of 3 to .p {
.s = (.s ^ 2 - 2) rem .mp
} == 0
}
writeln join " ", map f $"M\.... | Give a code snippet in #langur
Lucas-Lehmer Test:
for
p
{\displaystyle p}
an odd prime, the Mersenne number
2
p
−
1
{\displaystyle 2^{p}-1}
is prime if and only if
2
p
−
1
{\displaystyle 2^{p}-1}
divides
S
(
p
−
1
)
{\displaystyle S(p-1)}
where
S
(
n
+
1
)
=
(
S
(
n
)
)
2... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Keyboard_macros | Keyboard macros | Show how to link user defined methods to user defined keys.
An example of this is the facility provided by emacs for key bindings.
These key bindings may be application-specific or system-wide; state which you have done.
| #JavaScript | JavaScript | document.onkeydown = function(evt) {
if (evt.keyCode === 118) {
alert("You pressed F7!");
return false;
}
} | Give a code snippet in #JavaScript
Show how to link user defined methods to user defined keys.
An example of this is the facility provided by emacs for key bindings.
These key bindings may be application-specific or system-wide; state which you have done.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Dragon_curve | Dragon curve |
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by a left dragon, at 90-degree an... | #Run_BASIC | Run BASIC | graphic #g, 600,600
RL$ = "R"
loc = 90
pass = 0
[loop]
#g "cls ; home ; north ; down ; fill black"
for i =1 to len(RL$)
v = 255 * i /len(RL$)
#g "color "; v; " 120 "; 255 -v
#g "go "; loc
if mid$(RL$,i,1) ="R" then #g "turn 90" else #g "turn -90"
next i
#g "color 255 120 0"
#g "go "; loc
LR$ =""
for... | Give a code snippet in #Run_BASIC
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence:_smallest_number_greater_than_previous_term_with_exactly_n_divisors | Sequence: smallest number greater than previous term with exactly n divisors | Calculate the sequence where each term an is the smallest natural number greater than the previous term, that has exactly n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
See also
OEIS:A069654
Related tasks
Sequence: smallest number with exactly n divisors
Sequence: nth ... | #Raku | Raku | sub div-count (\x) {
return 2 if x.is-prime;
+flat (1 .. x.sqrt.floor).map: -> \d {
unless x % d { my \y = x div d; y == d ?? y !! (y, d) }
}
}
my $limit = 15;
my $m = 1;
put "First $limit terms of OEIS:A069654";
put (1..$limit).map: -> $n { my $ = $m = first { $n == .&div-count }, $m..Inf };
| Give a code snippet in #Raku
Calculate the sequence where each term an is the smallest natural number greater than the previous term, that has exactly n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
See also
OEIS:A069654
Related tasks
Sequence: smallest number with exac... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multi-dimensional_array | Multi-dimensional array | For the purposes of this task, the actual memory layout or access method of this data structure is not mandated.
It is enough to:
State the number and extent of each index to the array.
Provide specific, ordered, integer indices for all dimensions of the array together with a new value to update the indexed value.
... | #Ada | Ada |
type Grade is range 0..100;
subtype Lower_Case is Character range 'a'..'z';
subtype Natural is Integer range 0..Integer'Last;
subtype Positive is Integer range 1..Integer'Last;
type Deflection is range -180..180;
| Give a code snippet in #Ada
For the purposes of this task, the actual memory layout or access method of this data structure is not mandated.
It is enough to:
State the number and extent of each index to the array.
Provide specific, ordered, integer indices for all dimensions of the array together with a new value ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Copy_a_string | Copy a string | This task is about copying a string.
Task
Where it is relevant, distinguish between copying the contents of a string
versus making an additional reference to an existing string.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
W... | #F.23 | F# | let str = "hello"
let additionalReference = str
let deepCopy = System.String.Copy( str )
printfn "%b" <| System.Object.ReferenceEquals( str, additionalReference ) // prints true
printfn "%b" <| System.Object.ReferenceEquals( str, deepCopy ) // prints false | Give a code snippet in #F.23
This task is about copying a string.
Task
Where it is relevant, distinguish between copying the contents of a string
versus making an additional reference to an existing string.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty st... | christopher/rosetta-code | |
http://rosettacode.org/wiki/RSA_code | RSA code | Given an RSA key (n,e,d), construct a program to encrypt and decrypt plaintext messages strings.
Background
RSA code is used to encode secret messages. It is named after Ron Rivest, Adi Shamir, and Leonard Adleman who published it at MIT in 1977. The advantage of this type of encryption is that you can distribute the... | #Haskell | Haskell | module RSAMaker
where
import Data.Char ( chr )
encode :: String -> [Integer]
encode s = map (toInteger . fromEnum ) s
rsa_encode :: Integer -> Integer -> [Integer] -> [Integer]
rsa_encode n e numbers = map (\num -> mod ( num ^ e ) n ) numbers
rsa_decode :: Integer -> Integer -> [Integer] -> [Integer]
rsa_deco... | Give a code snippet in #Haskell
Given an RSA key (n,e,d), construct a program to encrypt and decrypt plaintext messages strings.
Background
RSA code is used to encode secret messages. It is named after Ron Rivest, Adi Shamir, and Leonard Adleman who published it at MIT in 1977. The advantage of this type of encrypti... | christopher/rosetta-code | |
http://rosettacode.org/wiki/URL_decoding | URL decoding | This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unencoded form "http://foo bar/".
Th... | #11l | 11l | F url_decode(s)
V r = ‘’
V i = 0
L i < s.len
I s[i] == ‘%’
[Byte] b
L i < s.len & s[i] == ‘%’
i++
b.append(Int(s[i.+2], radix' 16))
i += 2
r ‘’= b.decode(‘utf-8’)
E
r ‘’= s[i]
i++
R r
print(url_decode(‘http%3A%2F%... | Give a code snippet in #11l
This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unencoded fo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Last_Friday_of_each_month | Last Friday of each month | Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24
2012-03-30
2012-04-27
2012-05-25
20... | #SQL | SQL |
SELECT to_char( next_day( last_day( add_months( to_date(
:yr||'01','yyyymm' ),level-1))-7,'Fri') ,'yyyy-mm-dd Dy') lastfriday
FROM dual
CONNECT BY level <= 12;
| Give a code snippet in #SQL
Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24
2012-0... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_comments_from_a_string | Strip comments from a string | Strip comments from a string
You are encouraged to solve this task according to the task description, using any language you may know.
The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line.
Whitespace debacle: There is s... | #Python | Python | def remove_comments(line, sep):
for s in sep:
i = line.find(s)
if i >= 0:
line = line[:i]
return line.strip()
# test
print remove_comments('apples ; pears # and bananas', ';#')
print remove_comments('apples ; pears # and bananas', '!')
| Give a code snippet in #Python
Strip comments from a string
You are encouraged to solve this task according to the task description, using any language you may know.
The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gaussian_elimination | Gaussian elimination | Task
Solve Ax=b using Gaussian elimination then backwards substitution.
A being an n by n matrix.
Also, x and b are n by 1 vectors.
To improve accuracy, please use partial pivoting and scaling.
See also
the Wikipedia entry: Gaussian elimination
| #Stata | Stata | void gauss(real matrix a, real matrix b, real scalar det) {
real scalar i,j,n,s
real vector js
det = 1
n = rows(a)
for (i=1; i<n; i++) {
maxindex(abs(a[i::n,i]), 1, js=., .)
j = js[1]+i-1
if (j!=i) {
a[(i\j),i..n] = a[(j\i),i..n]
b[(i\j),.] = b[(j\i),.]
det = -det
}
for (j=i+1; j<=n; j++) {
... | Give a code snippet in #Stata
Task
Solve Ax=b using Gaussian elimination then backwards substitution.
A being an n by n matrix.
Also, x and b are n by 1 vectors.
To improve accuracy, please use partial pivoting and scaling.
See also
the Wikipedia entry: Gaussian elimination
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Dimensions | Terminal control/Dimensions | Determine the height and width of the terminal, and store this information into variables for subsequent use.
| #Go | Go | package main
import (
"fmt"
"os"
"golang.org/x/crypto/ssh/terminal"
)
func main() {
w, h, err := terminal.GetSize(int(os.Stdout.Fd()))
if err != nil {
fmt.Println(err)
return
}
fmt.Println(h, w)
} | Give a code snippet in #Go
Determine the height and width of the terminal, and store this information into variables for subsequent use.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Solve_a_Numbrix_puzzle | Solve a Numbrix puzzle | Numbrix puzzles are similar to Hidato.
The most important difference is that it is only possible to move 1 node left, right, up, or down (sometimes referred to as the Von Neumann neighborhood).
Published puzzles also tend not to have holes in the grid and may not always indicate the end node.
Two examples follow:
Exam... | #11l | 11l | V neighbours = [[-1, 0], [0, -1], [1, 0], [0, 1]]
[Int] exists
V lastNumber = 0
V wid = 0
V hei = 0
F find_next(pa, x, y, z)
L(i) 4
V a = x + :neighbours[i][0]
V b = y + :neighbours[i][1]
I a C -1 <.< :wid & b C -1 <.< :hei
I pa[a][b] == z
R (a, b)
R (-1, -1)
F find_solu... | Give a code snippet in #11l
Numbrix puzzles are similar to Hidato.
The most important difference is that it is only possible to move 1 node left, right, up, or down (sometimes referred to as the Von Neumann neighborhood).
Published puzzles also tend not to have holes in the grid and may not always indicate the end nod... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_a_series | Sum of a series | Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1
n
1
k
2
{\displa... | #ALGOL_68 | ALGOL 68 | MODE RANGE = STRUCT(INT lwb, upb);
PROC sum = (PROC (INT)LONG REAL f, RANGE range)LONG REAL:(
LONG REAL sum := LENG 0.0;
FOR i FROM lwb OF range TO upb OF range DO
sum := sum + f(i)
OD;
sum
);
test:(
RANGE range = (1,1000);
PROC f = (INT x)LONG REAL: LENG REAL(1) / LENG REAL(x)**2;
print(("Sum of... | Give a code snippet in #ALGOL_68
Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Attractive_numbers | Attractive numbers | A number is an attractive number if the number of its prime factors (whether distinct or not) is also prime.
Example
The number 20, whose prime decomposition is 2 × 2 × 5, is an attractive number because the number of its prime factors (3) is also prime.
Task
Show sequence items up to 120.... | #PL.2FM | PL/M | 100H:
BDOS: PROCEDURE (F, ARG); DECLARE F BYTE, ARG ADDRESS; GO TO 5; END BDOS;
EXIT: PROCEDURE; CALL BDOS(0,0); END EXIT;
PUT$CHAR: PROCEDURE (CH); DECLARE CH BYTE; CALL BDOS(2,CH); END PUT$CHAR;
DECLARE MAXIMUM LITERALLY '120';
PRINT4: PROCEDURE (N);
DECLARE (N, MAGN, Z) BYTE;
CALL PUT$CHAR(' ');
MAGN... | Give a code snippet in #PL.2FM
A number is an attractive number if the number of its prime factors (whether distinct or not) is also prime.
Example
The number 20, whose prime decomposition is 2 × 2 × 5, is an attractive number because the number of its prime factors (3) is also prime.
Task
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Text | Hello world/Text | Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
Hello world/Web server
| #IS-BASIC | IS-BASIC | PRINT "Hello world!" | Give a code snippet in #IS-BASIC
Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard erro... | christopher/rosetta-code |
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