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/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... | #Avail | Avail | Assert: 7! = 5040; | Give a code snippet in #Avail
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 n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Program_name | Program name | The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal A... | #Blue | Blue | global _start
: syscall ( num:eax -- result:eax ) syscall ;
: exit ( status:edi -- noret ) 60 syscall ;
: bye ( -- noret ) 0 exit ;
: write ( buf:esi len:edx fd:edi -- ) 1 syscall drop ;
1 const stdout
: print ( buf len -- ) stdout write ;
: newline ( -- ) s" \n" print ;
: println ( buf len -- ) print newli... | Give a code snippet in #Blue
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nested_function | Nested function | In many languages, functions can be nested, resulting in outer functions and inner functions. The inner function can access variables from the outer function. In most languages, the inner function can also modify variables in the outer function.
Task
Write a program consisting of two nested functions that prints t... | #ATS | ATS |
(* ****** ****** *)
//
#include
"share/atspre_staload.hats"
//
(* ****** ****** *)
fun
MakeList
(
sep: string
) : void = let
//
var count: int = 0
//
val count =
$UNSAFE.cast{ref(int)}(addr@count)
//
fun
MakeItem
(
item: string
) : void = let
val () = !count := !count+1
in
println! (!count, sep, item)
end... | Give a code snippet in #ATS
In many languages, functions can be nested, resulting in outer functions and inner functions. The inner function can access variables from the outer function. In most languages, the inner function can also modify variables in the outer function.
Task
Write a program consisting of two n... | 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 ... | #Common_Lisp | Common Lisp | (defun dot-product (a b)
(apply #'+ (mapcar #'* (coerce a 'list) (coerce b 'list)))) | Give a code snippet in #Common_Lisp
Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Abundant,_deficient_and_perfect_number_classifications | Abundant, deficient and perfect number classifications | These define three classifications of positive integers based on their proper divisors.
Let P(n) be the sum of the proper divisors of n where the proper divisors are all positive divisors of n other than n itself.
if P(n) < n then n is classed as deficient (OEIS A005100).
if P(n)... | #AArch64_Assembly | AArch64 Assembly |
/* ARM assembly AARCH64 Raspberry PI 3B or android 64 bits */
/* program numberClassif64.s */
/*******************************************/
/* Constantes file */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly*/
.include "... | Give a code snippet in #AArch64_Assembly
These define three classifications of positive integers based on their proper divisors.
Let P(n) be the sum of the proper divisors of n where the proper divisors are all positive divisors of n other than n itself.
if P(n) < n then n is classed as... | 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.
| #HicEst | HicEst |
CHARACTER date="March 7 2009 7:30pm EST", am_pm, result*20
EDIT(Text=date, Parse=cMonth, GetPosition=next)
month = 1 + EDIT(Text='January,February,March,April,May,June,July,August,September,October,November,December', Right=cMonth, Count=',' )
READ(Text=date(next:)) day, year, hour, minute, am_pm
hou... | Give a code snippet in #HicEst
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/Draw_a_sphere | Draw a sphere | Task
Draw a sphere.
The sphere can be represented graphically, or in ASCII art, depending on the language capabilities.
Either static or rotational projection is acceptable for this task.
Related tasks
draw a cuboid
draw a rotating cube
write language name in 3D ASCII
draw a Deathstar
| #LaTeX | LaTeX | \documentclass{minimal}
\usepackage{tikz}
\usetikzlibrary{shadings}
\begin{document}
\begin{tikzpicture}
\shade[ball color=black] (0,0) circle (4);
\end{tikzpicture}
\end{document} | Give a code snippet in #LaTeX
Task
Draw a sphere.
The sphere can be represented graphically, or in ASCII art, depending on the language capabilities.
Either static or rotational projection is acceptable for this task.
Related tasks
draw a cuboid
draw a rotating cube
write language name in 3D ASCII
draw a De... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Binary_search | Binary search | A binary search divides a range of values into halves, and continues to narrow down the field of search until the unknown value is found. It is the classic example of a "divide and conquer" algorithm.
As an analogy, consider the children's game "guess a number." The scorer has a secret number, and will only tell the p... | #Futhark | Futhark |
fun main(as: [n]int, value: int): int =
let low = 0
let high = n-1
loop ((low,high)) = while low <= high do
-- invariants: value > as[i] for all i < low
-- value < as[i] for all i > high
let mid = (low+high) / 2
in if as[mid] > value
then (low, mid - 1)
else if as[mid] ... | Give a code snippet in #Futhark
A binary search divides a range of values into halves, and continues to narrow down the field of search until the unknown value is found. It is the classic example of a "divide and conquer" algorithm.
As an analogy, consider the children's game "guess a number." The scorer has a secret... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Subtractive_generator | Subtractive generator | A subtractive generator calculates a sequence of random numbers, where each number is congruent to the subtraction of two previous numbers from the sequence.
The formula is
r
n
=
r
(
n
−
i
)
−
r
(
n
−
j
)
(
mod
m
)
{\displaystyle r_{n}=r_{(n-i)}-r_{(n-j)}{\pmod {m}}}
for some fixed values of... | #Elixir | Elixir | defmodule Subtractive do
def new(seed) when seed in 0..999_999_999 do
s = Enum.reduce(1..53, [1, seed], fn _,[a,b|_]=acc -> [b-a | acc] end)
|> Enum.reverse
|> List.to_tuple
state = for i <- 1..55, do: elem(s, rem(34*i, 55))
{:ok, _pid} = Agent.start_link(fn -> state end, name: :Subtractiv... | Give a code snippet in #Elixir
A subtractive generator calculates a sequence of random numbers, where each number is congruent to the subtraction of two previous numbers from the sequence.
The formula is
r
n
=
r
(
n
−
i
)
−
r
(
n
−
j
)
(
mod
m
)
{\displaystyle r_{n}=r_{(n-i)}-r_{(n-j)}{\pmod ... | 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... | #DCL | DCL | $ write sys$output f$fao( "!AS!-!AS!-!AS!-!AS!-!AS", "ha" )
$ write sys$output f$fao( "!12*d" ) | Give a code snippet in #DCL
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/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 |... | #PicoLisp | PicoLisp | : (pre? "ab" "abcd")
-> "abcd"
: (pre? "xy" "abcd")
-> NIL
: (sub? "bc" "abcd")
-> "abcd"
: (sub? "xy" "abcd")
-> NIL
: (tail (chop "cd") (chop "abcd"))
-> ("c" "d")
: (tail (chop "xy") (chop "abcd"))
-> NIL
(de positions (Pat Str)
(setq Pat (chop Pat))
(make
(for ((I . L) (chop Str) L (cdr L))
... | Give a code snippet in #PicoLisp
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/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #LiveCode | LiveCode | function reverseString S
repeat with i = length(S) down to 1
put char i of S after R
end repeat
return R
end reverseString | Give a code snippet in #LiveCode
Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Em... | christopher/rosetta-code | |
http://rosettacode.org/wiki/One-dimensional_cellular_automata | One-dimensional cellular automata | Assume an array of cells with an initial distribution of live and dead cells,
and imaginary cells off the end of the array having fixed values.
Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the current generation.
If, in the follow... | #Scala | Scala | def cellularAutomata(s: String) = {
def it = Iterator.iterate(s) ( generation =>
("_%s_" format generation).iterator
sliding 3
map (_ count (_ == '#'))
map Map(2 -> "#").withDefaultValue("_")
mkString
)
(it drop 1) zip it takeWhile Function.tupled(_ != _) map (_._2) foreach println
} | Give a code snippet in #Scala
Assume an array of cells with an initial distribution of live and dead cells,
and imaginary cells off the end of the array having fixed values.
Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the current... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Associative_array/Iteration | Associative array/Iteration | Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked ... | #Vala | Vala |
using Gee;
void main(){
// declare HashMap
var map = new HashMap<string, double?>();
// set 3 entries
map["pi"] = 3.14;
map["e"] = 2.72;
map["golden"] = 1.62;
// iter... | Give a code snippet in #Vala
Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Comp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fairshare_between_two_and_more | Fairshare between two and more | The Thue-Morse sequence is a sequence of ones and zeros that if two people
take turns in the given order, the first persons turn for every '0' in the
sequence, the second for every '1'; then this is shown to give a fairer, more
equitable sharing of resources. (Football penalty shoot-outs for example, might
not favour t... | #zkl | zkl | fcn fairShare(n,b){ // b<=36
n.pump(List,'wrap(n){ n.toString(b).split("").apply("toInt",b).sum(0)%b })
}
foreach b in (T(2,3,5,11)){
println("%2d: %s".fmt(b,fairShare(25,b).pump(String,"%2d ".fmt)));
} | Give a code snippet in #zkl
The Thue-Morse sequence is a sequence of ones and zeros that if two people
take turns in the given order, the first persons turn for every '0' in the
sequence, the second for every '1'; then this is shown to give a fairer, more
equitable sharing of resources. (Football penalty shoot-outs fo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/RIPEMD-160 | RIPEMD-160 | RIPEMD-160 is another hash function; it computes a 160-bit message digest.
There is a RIPEMD-160 home page, with test vectors and pseudocode for RIPEMD-160.
For padding the message, RIPEMD-160 acts like MD4 (RFC 1320).
Find the RIPEMD-160 message digest of a string of octets.
Use the ASCII encoded string “Rosetta Cod... | #Scala | Scala | import org.bouncycastle.crypto.digests.RIPEMD160Digest
object RosettaRIPEMD160 extends App {
val (raw, messageDigest) = ("Rosetta Code".getBytes("US-ASCII"), new RIPEMD160Digest())
messageDigest.update(raw, 0, raw.length)
val out = Array.fill[Byte](messageDigest.getDigestSize())(0)
messageDigest.doFinal(out, ... | Give a code snippet in #Scala
RIPEMD-160 is another hash function; it computes a 160-bit message digest.
There is a RIPEMD-160 home page, with test vectors and pseudocode for RIPEMD-160.
For padding the message, RIPEMD-160 acts like MD4 (RFC 1320).
Find the RIPEMD-160 message digest of a string of octets.
Use the AS... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Towers_of_Hanoi | Towers of Hanoi | Task
Solve the Towers of Hanoi problem with recursion.
| #Ursala | Ursala | #import nat
move = ~&al^& ^rlPlrrPCT/~&arhthPX ^|W/~& ^|G/predecessor ^/~&htxPC ~&zyxPC
#show+
main = ^|T(~&,' -> '--)* move/4 <'start','end','middle'> | Give a code snippet in #Ursala
Task
Solve the Towers of Hanoi problem with recursion.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #Perl | Perl | use strict;
sub halve { int((shift) / 2); }
sub double { (shift) * 2; }
sub iseven { ((shift) & 1) == 0; }
sub ethiopicmult
{
my ($plier, $plicand, $tutor) = @_;
print "ethiopic multiplication of $plier and $plicand\n" if $tutor;
my $r = 0;
while ($plier >= 1)
{
$r += $plicand unless iseven($pl... | Give a code snippet in #Perl
Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and wr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Perfect_totient_numbers | Perfect totient numbers | Generate and show here, the first twenty Perfect totient numbers.
Related task
Totient function
Also see
the OEIS entry for perfect totient numbers.
mrob list of the first 54
| #PL.2FM | PL/M | 100H:
BDOS: PROCEDURE (FN, ARG); DECLARE FN BYTE, ARG ADDRESS; GO TO 5; END BDOS;
EXIT: PROCEDURE; CALL BDOS(0,0); END EXIT;
PRINT: PROCEDURE (S); DECLARE S ADDRESS; CALL BDOS(9,S); END PRINT;
PRINT$NUMBER: PROCEDURE (N);
DECLARE S (7) BYTE INITIAL ('..... $');
DECLARE (N, P) ADDRESS, C BASED P BYTE;
P = ... | Give a code snippet in #PL.2FM
Generate and show here, the first twenty Perfect totient numbers.
Related task
Totient function
Also see
the OEIS entry for perfect totient numbers.
mrob list of the first 54
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Almost_prime | Almost prime | A k-Almost-prime is a natural number
n
{\displaystyle n}
that is the product of
k
{\displaystyle k}
(possibly identical) primes.
Example
1-almost-primes, where
k
=
1
{\displaystyle k=1}
, are the prime numbers themselves.
2-almost-primes, where
k
=
2
{\displaystyl... | #Modula-2 | Modula-2 | MODULE AlmostPrime;
FROM FormatString IMPORT FormatString;
FROM Terminal IMPORT WriteString,WriteLn,ReadChar;
PROCEDURE KPrime(n,k : INTEGER) : BOOLEAN;
VAR p,f : INTEGER;
BEGIN
f := 0;
p := 2;
WHILE (f<k) AND (p*p<=n) DO
WHILE n MOD p = 0 DO
n := n DIV p;
INC(f)
EN... | Give a code snippet in #Modula-2
A k-Almost-prime is a natural number
n
{\displaystyle n}
that is the product of
k
{\displaystyle k}
(possibly identical) primes.
Example
1-almost-primes, where
k
=
1
{\displaystyle k=1}
, are the prime numbers themselves.
2-almost-primes, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #PureBasic | PureBasic | Procedure Recur(n)
PrintN(str(n))
Recur(n+1)
EndProcedure
Recur(1) | Give a code snippet in #PureBasic
Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Special_variables | Special variables | Special variables have a predefined meaning within a computer programming language.
Task
List the special variables used within the language.
| #Phix | Phix | - Global variables start with an asterisk '*'
- Functions and other global symbols start with a lower case letter
- Locally bound symbols start with an upper case letter
- Local functions start with an underscore '_'
- Classes start with a plus-sign '+', where the first letter
- is in lower case for abstract classes... | Give a code snippet in #Phix
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/Barnsley_fern | Barnsley fern |
A Barnsley fern is a fractal named after British mathematician Michael Barnsley and can be created using an iterated function system (IFS).
Task
Create this fractal fern, using the following transformations:
ƒ1 (chosen 1% of the time)
xn + 1 = 0
yn + 1 = 0.16 yn
ƒ2 (chosen 85% of the time)
... | #Scala | Scala | import java.awt._
import java.awt.image.BufferedImage
import javax.swing._
object BarnsleyFern extends App {
SwingUtilities.invokeLater(() =>
new JFrame("Barnsley Fern") {
private class BarnsleyFern extends JPanel {
val dim = 640
val img = new BufferedImage(dim, dim, BufferedImage.TY... | Give a code snippet in #Scala
A Barnsley fern is a fractal named after British mathematician Michael Barnsley and can be created using an iterated function system (IFS).
Task
Create this fractal fern, using the following transformations:
ƒ1 (chosen 1% of the time)
xn + 1 = 0
yn + 1 = 0.16 yn
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/100_prisoners | 100 prisoners |
The Problem
100 prisoners are individually numbered 1 to 100
A room having a cupboard of 100 opaque drawers numbered 1 to 100, that cannot be seen from outside.
Cards numbered 1 to 100 are placed randomly, one to a drawer, and the drawers all closed; at the start.
Prisoners start outside the room
They can decid... | #Maple | Maple | p:=simplify(1-product(1-1/(2*n-k),k=0..n-1));
# p=1/2 | Give a code snippet in #Maple
The Problem
100 prisoners are individually numbered 1 to 100
A room having a cupboard of 100 opaque drawers numbered 1 to 100, that cannot be seen from outside.
Cards numbered 1 to 100 are placed randomly, one to a drawer, and the drawers all closed; at the start.
Prisoners start o... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest ... | #XPL0 | XPL0 | include c:\cxpl\codes; \intrinsic 'code' declarations
func real Power(X, Y); \X raised to the Y power
real X, Y;
return Exp(Y*Ln(X));
real E, Pi;
[Format(4, 16); \places shown before and after .
E:= Exp(1.0);
RlOut(0, E); CrLf(0);
RlOut(0, Ln(E)); CrLf(0);... | Give a code snippet in #XPL0
Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "ma... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Animation | Animation |
Animation is integral to many parts of GUIs, including both the fancy effects when things change used in window managers, and of course games. The core of any animation system is a scheme for periodically changing the display while still remaining responsive to the user. This task demonstrates this.
Task
Creat... | #Wren | Wren | import "graphics" for Canvas, Color
import "dome" for Window
import "input" for Mouse
var RIGHT = true
class Animation {
construct new() {
Window.title = "Animation"
_fore = Color.white
}
init() {
_text = "Hello World! "
_frame = 0
Canvas.print(_text, 10, 10, _f... | Give a code snippet in #Wren
Animation is integral to many parts of GUIs, including both the fancy effects when things change used in window managers, and of course games. The core of any animation system is a scheme for periodically changing the display while still remaining responsive to the user. This task dem... | 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)
| #J | J | isLeap=: 0 -/@:= 4 100 400 |/ ] | Give a code snippet in #J
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/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
| #Plain_English | Plain English | \This prints Hello World within the CAL-4700 IDE.
\...and backslashes are comments!
To run:
Start up.
Write "Hello World!" to the console.
Wait for the escape key.
Shut down. | Give a code snippet in #Plain_English
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... | 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... | #Visual_Basic_.NET | Visual Basic .NET | Imports System.Numerics
Module Module1
Sub Main()
Dim rd = {"22", "333", "4444", "55555", "666666", "7777777", "88888888", "999999999"}
Dim one As BigInteger = 1
Dim nine As BigInteger = 9
For ii = 2 To 9
Console.WriteLine("First 10 super-{0} numbers:", ii)
... | Give a code snippet in #Visual_Basic_.NET
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Literals/String | Literals/String | Task
Show literal specification of characters and strings.
If supported, show how the following work:
verbatim strings (quotes where escape sequences are quoted literally)
here-strings
Also, discuss which quotes expand variables.
Related tasks
Special characters
Here document
Other tasks r... | #Emacs_Lisp | Emacs Lisp | "This is a string." | Give a code snippet in #Emacs_Lisp
Task
Show literal specification of characters and strings.
If supported, show how the following work:
verbatim strings (quotes where escape sequences are quoted literally)
here-strings
Also, discuss which quotes expand variables.
Related tasks
Special characte... | christopher/rosetta-code | |
http://rosettacode.org/wiki/21_game | 21 game | 21 game
You are encouraged to solve this task according to the task description, using any language you may know.
21 is a two player game, the game is played by choosing
a number (1, 2, or 3) to be added to the running total.
The game is won by the player whose chosen number causes the running total
to reach exactly ... | #Perl | Perl | print <<'HERE';
The 21 game. Each player chooses to add 1, 2, or 3 to a running total.
The player whose turn it is when the total reaches 21 wins. Enter q to quit.
HERE
my $total = 0;
while () {
print "Running total is: $total\n";
my ($me,$comp);
while () {
print 'What number do you play> ';
... | Give a code snippet in #Perl
21 game
You are encouraged to solve this task according to the task description, using any language you may know.
21 is a two player game, the game is played by choosing
a number (1, 2, or 3) to be added to the running total.
The game is won by the player whose chosen number causes the r... | 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... | #C.23 | C# | using System;
class Program
{
static void Main(string[] args)
{
const int from = 1;
const int to = 10;
int randomNumber = new Random().Next(from, to);
int guessedNumber;
Console.Write("The number is between {0} and {1}. ", from, to);
while (true)
{
... | Give a code snippet in #C.23
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:
hig... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Infinite | Loops/Infinite | Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within l... | #Stata | Stata | while 1 {
display "SPAM"
} | Give a code snippet in #Stata
Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loop... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Narcissist | Narcissist | Quoting from the Esolangs wiki page:
A narcissist (or Narcissus program) is the decision-problem version of a quine.
A quine, when run, takes no input, but produces a copy of its own source code at its output. In contrast, a narcissist reads a string of symbols from its input, and produces no output except a "1" o... | #Nim | Nim |
import strutils; let a = "import strutils; let a = $#; echo ord(stdin.readAll == a % (chr(34) & a & chr(34)) & chr(10))"; echo ord(stdin.readAll == a % (chr(34) & a & chr(34)) & chr(10))
| Give a code snippet in #Nim
Quoting from the Esolangs wiki page:
A narcissist (or Narcissus program) is the decision-problem version of a quine.
A quine, when run, takes no input, but produces a copy of its own source code at its output. In contrast, a narcissist reads a string of symbols from its input, and prod... | christopher/rosetta-code | |
http://rosettacode.org/wiki/24_game | 24 game | The 24 Game tests one's mental arithmetic.
Task
Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed.
The program should prompt for the player to enter an arithmetic expression using just those, and all of those four digits, used exactly once each. T... | #Huginn | Huginn | #! /bin/sh
exec huginn --no-argv -E "${0}"
#! huginn
import Algorithms as algo;
import Mathematics as math;
import RegularExpressions as re;
make_game( rndGen_ ) {
board = "";
for ( i : algo.range( 4 ) ) {
board += ( " " + string( character( rndGen_.next() + integer( '1' ) ) ) );
}
return ( board.strip(... | Give a code snippet in #Huginn
The 24 Game tests one's mental arithmetic.
Task
Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed.
The program should prompt for the player to enter an arithmetic expression using just those, and all of those four d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For | Loops/For | “For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code.
Common extensions of this allow other counting patterns or iterating over abstract structures other than the integers.
... | #Picat | Picat | go =>
N = 5,
foreach(I in 1..N)
foreach(_J in 1..I)
print("*")
end,
nl
end. | Give a code snippet in #Picat
“For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code.
Common extensions of this allow other counting patterns or iterating over abstract structu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #MMIX | MMIX | A IS 17
B IS 34
pliar IS $255 % designating main registers
pliand GREG
acc GREG
str IS pliar % reuse reg $255 for printing
LOC Data_Segment
GREG @
BUF OCTA #3030303030303030 % reserve a buffer that is big enough to hold
OCTA #3030303030303030 % a max (signed) 64 bit integer:
OCTA #3030300a00000000 % 2^63 ... | Give a code snippet in #MMIX
Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and wr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roots_of_unity | Roots of unity | The purpose of this task is to explore working with complex numbers.
Task
Given n, find the nth roots of unity.
| #CoffeeScript | CoffeeScript | # Find the n nth-roots of 1
nth_roots_of_unity = (n) ->
(complex_unit_vector(2*Math.PI*i/n) for i in [1..n])
complex_unit_vector = (rad) ->
new Complex(Math.cos(rad), Math.sin(rad))
class Complex
constructor: (@real, @imag) ->
toString: ->
round_z = (n) ->
if Math.abs(n) < 0.00005 then 0 else n
... | Give a code snippet in #CoffeeScript
The purpose of this task is to explore working with complex numbers.
Task
Given n, find the nth roots of unity.
| 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)=(... | #Burlesque | Burlesque | 607rz2en{J4{J.*2.-2{th}c!**-..%}#R2.-E!n!it}f[2+]{2\/**-.}m[p^ | Give a code snippet in #Burlesque
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
)
)... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Send_an_unknown_method_call | Send an unknown method call | Task
Invoke an object method where the name of the method to be invoked can be generated at run time.
Related tasks
Respond to an unknown method call.
Runtime evaluation
| #Scala | Scala | class Example {
def foo(x: Int): Int = 42 + x
}
object Main extends App {
val example = new Example
val meth = example.getClass.getMethod("foo", classOf[Int])
assert(meth.invoke(example, 5.asInstanceOf[AnyRef]) == 47.asInstanceOf[AnyRef], "Not confirm expectation.")
println(s"Successfully completed with... | Give a code snippet in #Scala
Task
Invoke an object method where the name of the method to be invoked can be generated at run time.
Related tasks
Respond to an unknown method call.
Runtime evaluation
| 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
| #Nemerle | Nemerle | def isTerm = System.Console.IsOutputRedirected; | Give a code snippet in #Nemerle
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/Classes | Classes | In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T.
The first type T from the class T sometimes is called the root type of the class.
A class of types itself, a... | #Transd | Transd | #lang transd
class Point : {
x: Double(),
y: Double(),
@init: (λ v Vector<Double>() (= x (get v 0)) (= y (get v 1))),
print: (λ (textout "Point(" x "; " y ")\n" ))
}
MainModule: {
v_: [[1.0, 2.0], [3.0, 4.0]],
_start: (λ
// creating an instance of class
(with pt Point([5.0, 6.0])
... | Give a code snippet in #Transd
In object-oriented programming class is a set (a transitive closure) of types bound by the relation of inheritance. It is said that all types derived from some base type T and the type T itself form a class T.
The first type T from the class T sometimes is called the root type of the cl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/XML/XPath | XML/XPath | Perform the following three XPath queries on the XML Document below:
//item[1]: Retrieve the first "item" element
//price/text(): Perform an action on each "price" element (print it out)
//name: Get an array of all the "name" elements
XML Document:
<inventory title="OmniCorp Store #45x10^3">
<section name="heal... | #Perl | Perl | use XML::XPath qw();
my $x = XML::XPath->new('<inventory ... </inventory>');
[$x->findnodes('//item[1]')->get_nodelist]->[0];
print $x->findnodes_as_string('//price');
$x->findnodes('//name')->get_nodelist; | Give a code snippet in #Perl
Perform the following three XPath queries on the XML Document below:
//item[1]: Retrieve the first "item" element
//price/text(): Perform an action on each "price" element (print it out)
//name: Get an array of all the "name" elements
XML Document:
<inventory title="OmniCorp Store #4... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Variable-length_quantity | Variable-length quantity | Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable.
Task
With above operations,
convert these two numbers 0x200000 (209... | #Perl | Perl |
use warnings;
use strict;
for my $testcase (
0, 0xa, 123, 254, 255, 256,
257, 65534, 65535, 65536, 65537, 0x1fffff,
0x200000
)
{
my @vlq = vlq_encode($testcase);
printf "%8s %12s %8s\n", $testcase, ( join ':', @vlq ), vlq_decode(@vlq);
}
sub vlq_encode {
my @vlq;
my $binary... | Give a code snippet in #Perl
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable.
Task
With above operations,
convert t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Brownian_tree | Brownian tree | Brownian tree
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw a Brownian Tree.
A Brownian Tree is generated as a result of an initial seed, followed by the interaction of two processes.
The initial "seed" is placed somewhere wi... | #Julia | Julia | using Images, FileIO
function main(h::Integer, w::Integer, side::Bool=false)
W0 = w >> 1
H0 = h >> 1
@inline function motecolor(x::Integer, y::Integer)
h = clamp(180 * (atan2(y - H0, x - W0) / π + 1.0), 0.0, 360.0)
return HSV(h, 0.5, 0.5)
end
img = zeros(RGB{N0f8}, h, w)
img[... | Give a code snippet in #Julia
Brownian tree
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw a Brownian Tree.
A Brownian Tree is generated as a result of an initial seed, followed by the interaction of two processes.
The initia... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_common_directory_path | Find common directory path | Create a routine that, given a set of strings representing directory paths and a single character directory separator, will return a string representing that part of the directory tree that is common to all the directories.
Test your routine using the forward slash '/' character as the directory separator and the foll... | #PicoLisp | PicoLisp | (de commonPath (Lst Chr)
(glue Chr
(make
(apply find
(mapcar '((L) (split (chop L) Chr)) Lst)
'(@ (or (pass <>) (nil (link (next))))) ) ) ) ) | Give a code snippet in #PicoLisp
Create a routine that, given a set of strings representing directory paths and a single character directory separator, will return a string representing that part of the directory tree that is common to all the directories.
Test your routine using the forward slash '/' character as th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included) | Arbitrary-precision integers (included) | Using the in-built capabilities of your language, calculate the integer value of:
5
4
3
2
... | #Emacs_Lisp | Emacs Lisp | (let* ((integer-width (* 65536 16)) ; raise bignum limit from 65536 bits to avoid overflow error
(answer (number-to-string (expt 5 (expt 4 (expt 3 2)))))
(length (length answer)))
(message "%s has %d digits"
(if (> length 40)
(format "%s...%s"
(substring answer 0 20)
(subst... | Give a code snippet in #Emacs_Lisp
Using the in-built capabilities of your language, calculate the integer value of:
5
4
3
2
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Walk_a_directory/Recursively | Walk a directory/Recursively | Task
Walk a given directory tree and print files matching a given pattern.
Note: This task is for recursive methods. These tasks should read an entire directory tree, not a single directory.
Note: Please be careful when running any code examples found here.
Related task
Walk a directory/Non-recursively ... | #F.23 | F# | open System.IO
let rec getAllFiles dir pattern =
seq { yield! Directory.EnumerateFiles(dir, pattern)
for d in Directory.EnumerateDirectories(dir) do
yield! getAllFiles d pattern }
getAllFiles "c:\\temp" "*.xml"
|> Seq.iter (printfn "%s") | Give a code snippet in #F.23
Task
Walk a given directory tree and print files matching a given pattern.
Note: This task is for recursive methods. These tasks should read an entire directory tree, not a single directory.
Note: Please be careful when running any code examples found here.
Related task
Walk ... | 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... | #Vala | Vala |
void main(){
const int from = 1;
const int to = 100;
int random = Random.int_range(from, to);
int guess = 0;
while (guess != random){
stdout.printf("Guess the target number that's between %d and %d.\n", from, to);
string? num = stdin.read_line ();
num.canon("0123456789", '!'); // replaces any charac... | Give a code snippet in #Vala
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:
hig... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Angle_difference_between_two_bearings | Angle difference between two bearings | Finding the angle between two bearings is often confusing.[1]
Task
Find the angle which is the result of the subtraction b2 - b1, where b1 and b2 are the bearings.
Input bearings are expressed in the range -180 to +180 degrees.
The result is also expressed in the range -180 to +180 degrees.
... | #Sidef | Sidef | func bearingAngleDiff(b1, b2) {
(var b = ((b2 - b1 + 720) % 360)) > 180 ? (b - 360) : b
}
printf("%25s %25s %25s\n", "B1", "B2", "Difference")
printf("%25s %25s %25s\n", "-"*20, "-"*20, "-"*20)
for b1,b2 in ([
20, 45
-45, ... | Give a code snippet in #Sidef
Finding the angle between two bearings is often confusing.[1]
Task
Find the angle which is the result of the subtraction b2 - b1, where b1 and b2 are the bearings.
Input bearings are expressed in the range -180 to +180 degrees.
The result is also expressed in the range ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Brownian_tree | Brownian tree | Brownian tree
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw a Brownian Tree.
A Brownian Tree is generated as a result of an initial seed, followed by the interaction of two processes.
The initial "seed" is placed somewhere wi... | #Common_Lisp | Common Lisp | ;;; brownian.lisp
;;; sbcl compile: first load and then (sb-ext:save-lisp-and-die "brownian" :executable t :toplevel #'brownian::main)
(ql:quickload "cl-gd")
(defpackage #:brownian
(:use #:cl #:cl-gd))
(in-package #:brownian)
(defvar *size* 512)
(defparameter bitmap (make-array *size*))
(dotimes (i *size*)
(set... | Give a code snippet in #Common_Lisp
Brownian tree
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw a Brownian Tree.
A Brownian Tree is generated as a result of an initial seed, followed by the interaction of two processes.
The ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parameterized_SQL_statement | Parameterized SQL statement | SQL injection
Using a SQL update statement like this one (spacing is optional):
UPDATE players
SET name = 'Smith, Steve', score = 42, active = TRUE
WHERE jerseyNum = 99
Non-parameterized SQL is the GoTo statement of database programming. Don't do it, and make sure your coworkers don't either. | #Ada | Ada | -- Version for sqlite
with GNATCOLL.SQL_Impl; use GNATCOLL.SQL_Impl;
with GNATCOLL.SQL.Exec; use GNATCOLL.SQL.Exec;
with GNATCOLL.SQL.Sqlite; use GNATCOLL.SQL;
procedure Prepared_Query is
DB_Descr : Database_Description;
Conn : Database_Connection;
Query : Prepared_Statement;
--sqlite does no... | Give a code snippet in #Ada
SQL injection
Using a SQL update statement like this one (spacing is optional):
UPDATE players
SET name = 'Smith, Steve', score = 42, active = TRUE
WHERE jerseyNum = 99
Non-parameterized SQL is the GoTo statement of database programming. Don't do it, and make sure your coworkers don'... | 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... | #zkl | zkl | # Pyramid solver
# [151]
# [ ] [ ]
# [ 40] [ ] [ ]
# [ ] [ ] [ ] [ ]
#[ X ] [ 11] [ Y ] [ 4 ] [ Z ]
# Known: X - Y + Z = 0
p:=T( L(151), L(Void,Void), L(40,Void,Void), L(Void,Void,Void,Void),
L("X", 11, "Y", 4, "Z") );
addlConstraint:=Dictionary( "X",1, "Y",-1, "Z",1, ... | Give a code snippet in #zkl
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Binary_strings | Binary strings | Many languages have powerful and useful (binary safe) string manipulation functions, while others don't, making it harder for these languages to accomplish some tasks.
This task is about creating functions to handle binary strings (strings made of arbitrary bytes, i.e. byte strings according to Wikipedia) for those la... | #D | D | void main() /*@safe*/ {
import std.array: empty, replace;
import std.string: representation, assumeUTF;
// String creation (destruction is usually handled by
// the garbage collector).
ubyte[] str1;
// String assignments.
str1 = "blah".dup.representation;
// Hex string, same as "\x00... | Give a code snippet in #D
Many languages have powerful and useful (binary safe) string manipulation functions, while others don't, making it harder for these languages to accomplish some tasks.
This task is about creating functions to handle binary strings (strings made of arbitrary bytes, i.e. byte strings according... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fusc_sequence | Fusc sequence |
Definitions
The fusc integer sequence is defined as:
fusc(0) = 0
fusc(1) = 1
for n>1, the nth term is defined as:
if n is even; fusc(n) = fusc(n/2)
if n is odd; fusc(n) = fusc((n-1)/2) + fusc((n+1)/2)
Note that MathWorld's definition starts with unity, not zero. Th... | #CLU | CLU | fusc = iter () yields (int)
q: array[int] := array[int]$[1]
yield(0)
yield(1)
while true do
x: int := array[int]$reml(q)
array[int]$addh(q,x)
yield(x)
x := x + array[int]$bottom(q)
array[int]$addh(q,x)
yield(x)
end
end fusc
longest_fusc = iter ()... | Give a code snippet in #CLU
Definitions
The fusc integer sequence is defined as:
fusc(0) = 0
fusc(1) = 1
for n>1, the nth term is defined as:
if n is even; fusc(n) = fusc(n/2)
if n is odd; fusc(n) = fusc((n-1)/2) + fusc((n+1)/2)
Note that MathWorld's definition star... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #Lingo | Lingo | fp = xtra("fileIO").new()
fp.openFile(_movie.path & "input.txt", 1)
fileSize = fp.getLength()
repeat while TRUE
str = fp.readLine()
if str.char[1] = numtochar(10) then delete char 1 of str
if the last char of str = numtochar(13) then delete the last char of str
put str
if fp.getPosition()>=fileSize then exit ... | Give a code snippet in #Lingo
Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Safe_primes_and_unsafe_primes | Safe primes and unsafe primes | Definitions
A safe prime is a prime p and where (p-1)/2 is also prime.
The corresponding prime (p-1)/2 is known as a Sophie Germain prime.
An unsafe prime is a prime p and where (p-1)/2 isn't a prime.
An unsafe prime is a prime that isn't a safe prime.
Task
... | #F.23 | F# |
pCache |> Seq.filter(fun n->isPrime((n-1)/2)) |> Seq.take 35 |> Seq.iter (printf "%d ")
| Give a code snippet in #F.23
Definitions
A safe prime is a prime p and where (p-1)/2 is also prime.
The corresponding prime (p-1)/2 is known as a Sophie Germain prime.
An unsafe prime is a prime p and where (p-1)/2 isn't a prime.
An unsafe prime is a prime that isn't... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Exceptions | Exceptions | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
This task is to give an example of an exception handling routine
and to "throw" a new exception.
Related task
Exceptions Through Nested Calls
| #Slate | Slate | se@(SceneElement traits) doWithRestart: block
[
block handlingCases: {Abort -> [| :_ | ^ Nil]}
]. | Give a code snippet in #Slate
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
This task is to give an example of an exception handling routine
and to "throw" a new exception.
Related task
Exceptions... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Vector_products | Vector products | A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of numbers, (X, Y, Z) would repr... | #GLSL | GLSL |
vec3 a = vec3(3, 4, 5),b = vec3(4, 3, 5),c = vec3(-5, -12, -13);
float dotProduct(vec3 a, vec3 b)
{
return a.x*b.x+a.y*b.y+a.z*b.z;
}
vec3 crossProduct(vec3 a,vec3 b)
{
vec3 c = vec3(a.y*b.z - a.z*b.y, a.z*b.x - a.x*b.z, a.x*b.y- a.y*b.x);
return c;
}
float scalarTripleProduct(vec3 a,vec3 b,vec3 c)
{
retu... | Give a code snippet in #GLSL
A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of num... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic/Integer | Arithmetic/Integer |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Raku | Raku | my Int $a = get.floor;
my Int $b = get.floor;
say 'sum: ', $a + $b;
say 'difference: ', $a - $b;
say 'product: ', $a * $b;
say 'integer quotient: ', $a div $b;
say 'remainder: ', $a % $b;
say 'exponentiation: ', $a**$b; | Give a code snippet in #Raku
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
C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/A%2BB | A+B | A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated by space(s):
(
−
1000
≤... | #Rockstar | Rockstar |
Listen to A number
Listen to B
Say A number plus B
| Give a code snippet in #Rockstar
A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/War_card_game | War card game | War Card Game
Simulate the card game War. Use the Bicycle playing card manufacturer's rules. Show a game as played. User input is optional.
References:
Bicycle card company: War game site
Wikipedia: War (card game)
Related tasks:
Playing cards
Card shuffles
Deal cards for FreeCell
Poker hand_analyser
Go Fish... | #Lua | Lua | -- main.lua
function newGame ()
-- new deck
local deck = {}
for iSuit = 1, #CardSuits do
for iRank = 1, #CardRanks do
local card = {
iSuit = iSuit,
iRank = iRank,
suit = CardSuits[iSuit],
rank = iRank,
name = CardRanks[iRank] .. CardSuits[iSuit]
}
local i = math.random (#deck + 1)
t... | Give a code snippet in #Lua
War Card Game
Simulate the card game War. Use the Bicycle playing card manufacturer's rules. Show a game as played. User input is optional.
References:
Bicycle card company: War game site
Wikipedia: War (card game)
Related tasks:
Playing cards
Card shuffles
Deal cards for FreeCell
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_composition | Function composition | Task
Create a function, compose, whose two arguments f and g, are both functions with one argument.
The result of compose is to be a function of one argument, (lets call the argument x), which works like applying function f to the result of applying function g to x.
Example
compose... | #EchoLisp | EchoLisp |
;; By decreasing order of performance
;; 1) user definition : lambda and closure
(define (ucompose f g ) (lambda (x) ( f ( g x))))
(ucompose sin cos)
→ (🔒 λ (_x) (f (g _x)))
;; 2) built-in compose : lambda
(compose sin cos)
→ (λ (_#:g1002) (#apply-compose (#list #cos #sin) _#:g1002))
;; 3) compiled com... | Give a code snippet in #EchoLisp
Task
Create a function, compose, whose two arguments f and g, are both functions with one argument.
The result of compose is to be a function of one argument, (lets call the argument x), which works like applying function f to the result of applying function ... | 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.
| #C.2B.2B | C++ | #include <thread>
#include <iostream>
#include <vector>
#include <random>
#include <chrono>
int main()
{
std::random_device rd;
std::mt19937 eng(rd()); // mt19937 generator with a hardware random seed.
std::uniform_int_distribution<> dist(1,1000);
std::vector<std::thread> threads;
for(const auto& str: {"... | Give a code snippet in #C.2B.2B
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determinant_and_permanent | Determinant and permanent | For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while the permanent is given by
... | #zkl | zkl | var [const] GSL=Import("zklGSL"); // libGSL (GNU Scientific Library)
fcn perm(A){ // should verify A is square
numRows:=A.rows;
Utils.Helpers.permute(numRows.toList()).reduce( // permute(0,1,..numRows)
'wrap(s,pm){ s + numRows.reduce('wrap(x,i){ x*A[i,pm[i]] },1.0) },
0.0)
}
test:=fcn(A){
println... | Give a code snippet in #zkl
For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Caesar_cipher | Caesar cipher |
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A).
So key 2 encrypts "HI" to... | #Modula-2 | Modula-2 | MODULE CaesarCipher;
FROM Conversions IMPORT IntToStr;
FROM Terminal IMPORT WriteString, WriteLn, ReadChar;
TYPE String = ARRAY[0..64] OF CHAR;
PROCEDURE Encrypt(p : String; key : CARDINAL) : String;
VAR e : String;
VAR i,t : CARDINAL;
VAR c : CHAR;
BEGIN
FOR i:=0 TO HIGH(p) DO
IF p[i]=0C THEN BREAK; EN... | Give a code snippet in #Modula-2
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Factorions | Factorions |
Definition
A factorion is a natural number that equals the sum of the factorials of its digits.
Example
145 is a factorion in base 10 because:
1! + 4! + 5! = 1 + 24 + 120 = 145
It can be shown (see talk page) that no factorion in base 10 can exceed 1,499,999.
Task
Write a progr... | #Pascal | Pascal | program munchhausennumber;
{$IFDEF FPC}{$MODE objFPC}{$Optimization,On,all}{$ELSE}{$APPTYPE CONSOLE}{$ENDIF}
uses
sysutils;
type
tdigit = byte;
const
MAXBASE = 17;
var
DgtPotDgt : array[0..MAXBASE-1] of NativeUint;
dgtCnt : array[0..MAXBASE-1] of NativeInt;
cnt: NativeUint;
function convertToString(n:N... | Give a code snippet in #Pascal
Definition
A factorion is a natural number that equals the sum of the factorials of its digits.
Example
145 is a factorion in base 10 because:
1! + 4! + 5! = 1 + 24 + 120 = 145
It can be shown (see talk page) that no factorion in base 10 can exceed 1... | 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 |... | #Groovy | Groovy | def comparison = { a, b ->
println "a ? b = ${a} ? ${b} = a ${a < b ? '<' : a > b ? '>' : a == b ? '==' : '?'} b"
} | Give a code snippet in #Groovy
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/Least_common_multiple | Least common multiple | Least common multiple
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Compute the least common multiple (LCM) of two integers.
Given m and n, the least common multiple is the smallest positive integer that has both m and n as factor... | #ATS | ATS | #define ATS_DYNLOADFLAG 0 (* No initialization is needed. *)
#include "share/atspre_define.hats"
#include "share/atspre_staload.hats"
(********************************************************************)
(* *)
(* Declarations. ... | Give a code snippet in #ATS
Least common multiple
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Compute the least common multiple (LCM) of two integers.
Given m and n, the least common multiple is the smallest positive integer that has b... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_whitespace_from_a_string/Top_and_tail | Strip whitespace from a string/Top and tail | Task
Demonstrate how to strip leading and trailing whitespace from a string.
The solution should demonstrate how to achieve the following three results:
String with leading whitespace removed
String with trailing whitespace removed
String with both leading and trailing whitespace removed
For the purposes of thi... | #OCaml | OCaml | let left_pos s len =
let rec aux i =
if i >= len then None
else match s.[i] with
| ' ' | '\n' | '\t' | '\r' -> aux (succ i)
| _ -> Some i
in
aux 0
let right_pos s len =
let rec aux i =
if i < 0 then None
else match s.[i] with
| ' ' | '\n' | '\t' | '\r' -> aux (pred i)
| _ -> So... | Give a code snippet in #OCaml
Task
Demonstrate how to strip leading and trailing whitespace from a string.
The solution should demonstrate how to achieve the following three results:
String with leading whitespace removed
String with trailing whitespace removed
String with both leading and trailing whitespace re... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Evolutionary_algorithm | Evolutionary algorithm | Starting with:
The target string: "METHINKS IT IS LIKE A WEASEL".
An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent).
A fitness function that computes the ‘closeness’ of its argument to the target string.... | #AWK | AWK |
#!/bin/awk -f
function randchar(){
return substr(charset,randint(length(charset)+1),1)
}
function mutate(gene,rate ,l,newgene){
newgene = ""
for (l=1; l < 1+length(gene); l++){
if (rand() < rate)
newgene = newgene randchar()
else
newgene = newgene substr(gene,l,1)
}
return newgene
}
function fitness(gene,tar... | Give a code snippet in #AWK
Starting with:
The target string: "METHINKS IT IS LIKE A WEASEL".
An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent).
A fitness function that computes the ‘closeness’ of its a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Largest_number_divisible_by_its_digits | Largest number divisible by its digits | Task
Find the largest base 10 integer whose digits are all different, and is evenly divisible by each of its individual digits.
These numbers are also known as Lynch-Bell numbers, numbers n such that the
(base ten) digits are all different (and do not include zero) and n is divisible by each of it... | #Ruby | Ruby | magic_number = 9*8*7
div = 9876432.div(magic_number) * magic_number
candidates = div.step(0, -magic_number)
res = candidates.find do |c|
digits = c.digits
(digits & [0,5]).empty? && digits == digits.uniq
end
puts "Largest decimal number is #{res}" | Give a code snippet in #Ruby
Task
Find the largest base 10 integer whose digits are all different, and is evenly divisible by each of its individual digits.
These numbers are also known as Lynch-Bell numbers, numbers n such that the
(base ten) digits are all different (and do not include zero) and ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap | Bitmap | Show a basic storage type to handle a simple RGB raster graphics image,
and some primitive associated functions.
If possible provide a function to allocate an uninitialised image,
given its width and height, and provide 3 additional functions:
one to fill an image with a plain RGB color,
one to set a given pixe... | #RapidQ | RapidQ | DECLARE SUB PaintCanvas
CREATE form AS QForm
Width = 640
Height = 480
CREATE canvas AS QCanvas
Height = form.ClientHeight
Width = form.ClientWidth
OnPaint = PaintCanvas
END CREATE
END CREATE
SUB PaintCanvas
' Fill background
canvas.FillRect(0, 0, canvas.Width, canvas.Height, &H... | Give a code snippet in #RapidQ
Show a basic storage type to handle a simple RGB raster graphics image,
and some primitive associated functions.
If possible provide a function to allocate an uninitialised image,
given its width and height, and provide 3 additional functions:
one to fill an image with a plain RGB c... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic_evaluation | Arithmetic evaluation | Create a program which parses and evaluates arithmetic expressions.
Requirements
An abstract-syntax tree (AST) for the expression must be created from parsing the input.
The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.)
The ... | #Picat | Picat | main =>
print("Enter an expression: "),
Str = read_line(),
Exp = parse_term(Str),
Res is Exp,
printf("Result = %w\n", Res).
| Give a code snippet in #Picat
Create a program which parses and evaluates arithmetic expressions.
Requirements
An abstract-syntax tree (AST) for the expression must be created from parsing the input.
The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a si... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Compound_data_type | Compound data type |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Task
Create a compound data type:
Point(x,y)
A compound data type is one that holds multiple independent values.
Related task
Enumeration
S... | #Sidef | Sidef | struct Point {x, y};
var point = Point(1, 2);
say point.y; #=> 2 | Give a code snippet in #Sidef
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Task
Create a compound data type:
Point(x,y)
A compound data type is one that holds multiple independent values.
R... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case... | #Emacs_Lisp | Emacs Lisp | (setq my-variable (with-temp-buffer
(insert-file-contents "foo.txt")
(buffer-string))) | Give a code snippet in #Emacs_Lisp
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Literals/Floating_point | Literals/Floating point | Programming languages have different ways of expressing floating-point literals.
Task
Show how floating-point literals can be expressed in your language: decimal or other bases, exponential notation, and any other special features.
You may want to include a regular expression or BNF/ABNF/EBNF defining allowable fo... | #Eiffel | Eiffel |
1.
1.23
1e-5
.5
1.23E4
| Give a code snippet in #Eiffel
Programming languages have different ways of expressing floating-point literals.
Task
Show how floating-point literals can be expressed in your language: decimal or other bases, exponential notation, and any other special features.
You may want to include a regular expression or BNF... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Man_or_boy_test | Man or boy test | Man or boy test
You are encouraged to solve this task according to the task description, using any language you may know.
Background: The man or boy test was proposed by computer scientist Donald Knuth as a means of evaluating implementations of the ALGOL 60 programming language. The aim of the test was to distinguis... | #C | C | /* man-or-boy.c */
#include <stdio.h>
#include <stdlib.h>
// --- thunks
typedef struct arg
{
int (*fn)(struct arg*);
int *k;
struct arg *x1, *x2, *x3, *x4, *x5;
} ARG;
// --- lambdas
int f_1 (ARG* _) { return -1; }
int f0 (ARG* _) { return 0; }
int f1 (ARG* _) { return 1; }
// --- helper
in... | Give a code snippet in #C
Man or boy test
You are encouraged to solve this task according to the task description, using any language you may know.
Background: The man or boy test was proposed by computer scientist Donald Knuth as a means of evaluating implementations of the ALGOL 60 programming language. The aim of... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Factors_of_a_Mersenne_number | Factors of a Mersenne number | A Mersenne number is a number in the form of 2P-1.
If P is prime, the Mersenne number may be a Mersenne prime
(if P is not prime, the Mersenne number is also not prime).
In the search for Mersenne prime numbers it is advantageous to eliminate exponents by finding a small factor before starting a, potentially lengthy,... | #Lingo | Lingo | on modPow (b, e, m)
bits = getBits(e)
sq = 1
repeat while TRUE
tb = bits[1]
bits.deleteAt(1)
sq = sq*sq
if tb then sq=sq*b
sq = sq mod m
if bits.count=0 then return sq
end repeat
end
on getBits (n)
bits = []
f = 1
repeat while TRUE
bi... | Give a code snippet in #Lingo
A Mersenne number is a number in the form of 2P-1.
If P is prime, the Mersenne number may be a Mersenne prime
(if P is not prime, the Mersenne number is also not prime).
In the search for Mersenne prime numbers it is advantageous to eliminate exponents by finding a small factor before s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Egyptian_fractions | Egyptian fractions | An Egyptian fraction is the sum of distinct unit fractions such as:
1
2
+
1
3
+
1
16
(
=
43
48
)
{\displaystyle {\tfrac {1}{2}}+{\tfrac {1}{3}}+{\tfrac {1}{16}}\,(={\tfrac {43}{48}})}
Each fraction in the expression has a numerator equal to 1 (unity) and a denominator that... | #Kotlin | Kotlin | // version 1.2.10
import java.math.BigInteger
import java.math.BigDecimal
import java.math.MathContext
val bigZero = BigInteger.ZERO
val bigOne = BigInteger.ONE
val bdZero = BigDecimal.ZERO
val context = MathContext.UNLIMITED
fun gcd(a: BigInteger, b: BigInteger): BigInteger
= if (b == bigZero) a else gcd(b... | Give a code snippet in #Kotlin
An Egyptian fraction is the sum of distinct unit fractions such as:
1
2
+
1
3
+
1
16
(
=
43
48
)
{\displaystyle {\tfrac {1}{2}}+{\tfrac {1}{3}}+{\tfrac {1}{16}}\,(={\tfrac {43}{48}})}
Each fraction in the expression has a numerator equal to 1 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Associative_array/Iteration | Associative array/Iteration | Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked ... | #Prolog | Prolog |
assert( mymap(key1,value1) ).
assert( mymap(key2,value1) ).
| Give a code snippet in #Prolog
Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_definition | Function definition | A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract from showing how functions are ... | #AutoHotkey | AutoHotkey | MsgBox % multiply(10,2)
multiply(multiplicand, multiplier) {
Return (multiplicand * multiplier)
} | Give a code snippet in #AutoHotkey
A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to dist... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Base64_decode_data | Base64 decode data | See Base64 encode data.
Now write a program that takes the output of the Base64 encode data task as input and regenerate the original file.
When working on the VBA implementation I found several 'solutions' on the net, including one from the software maker himself, that showed output with incorrect padding. Obviously... | #Arturo | Arturo | text: "VG8gZXJyIGlzIGh1bWFuLCBidXQgdG8gcmVhbGx5IGZvdWwgdGhpbmdzIHVwIHlvdSBuZWVkIGEgY29tcHV0ZXIuCiAgICAtLSBQYXVsIFIuIEVocmxpY2g="
print decode text | Give a code snippet in #Arturo
See Base64 encode data.
Now write a program that takes the output of the Base64 encode data task as input and regenerate the original file.
When working on the VBA implementation I found several 'solutions' on the net, including one from the software maker himself, that showed output w... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Self-describing_numbers | Self-describing numbers | Self-describing numbers
You are encouraged to solve this task according to the task description, using any language you may know.
There are several so-called "self-describing" or "self-descriptive" integers.
An integer is said to be "self-describing" if it has the property that, when digit positions are labeled 0 to ... | #XPL0 | XPL0 | code ChOut=8, IntOut=11;
func SelfDesc(N); \Returns 'true' if N is self-describing
int N;
int Len, \length = number of digits in N
I, D;
char Digit(10), Count(10);
proc Num2Str(N); \Convert integer N to string in Digit
int N;
int R;
[N:= N/10;
... | Give a code snippet in #XPL0
Self-describing numbers
You are encouraged to solve this task according to the task description, using any language you may know.
There are several so-called "self-describing" or "self-descriptive" integers.
An integer is said to be "self-describing" if it has the property that, when dig... | christopher/rosetta-code | |
http://rosettacode.org/wiki/4-rings_or_4-squares_puzzle | 4-rings or 4-squares puzzle | 4-rings or 4-squares puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Replace a, b, c, d, e, f, and
g with the decimal
digits LOW ───► HIGH
such that the sum of the letters inside of each of the four large squares add up to
t... | #Fortran | Fortran | WRITE(...) FIRST,LAST,IF (UNIQUE) THEN "Distinct values only" ELSE "Repeated values allowed" FI // "." | Give a code snippet in #Fortran
4-rings or 4-squares puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Replace a, b, c, d, e, f, and
g with the decimal
digits LOW ───► HIGH
such that the sum of the letters inside of each of t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #MAXScript | MAXScript | -- Here
deleteFile "input.txt"
-- Root
deleteFile "\input.txt" | Give a code snippet in #MAXScript
Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Null_object | Null object |
Null (or nil) is the computer science concept of an undefined or unbound object.
Some languages have an explicit way to access the null object, and some don't.
Some languages distinguish the null object from undefined values, and some don't.
Task
Show how to access null in your language by checking to see if an ob... | #C.2B.2B | C++ | #include <iostream>
#include <cstdlib>
if (object == 0) {
std::cout << "object is null";
} | Give a code snippet in #C.2B.2B
Null (or nil) is the computer science concept of an undefined or unbound object.
Some languages have an explicit way to access the null object, and some don't.
Some languages distinguish the null object from undefined values, and some don't.
Task
Show how to access null in your lan... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Undefined_values | Undefined values | #Factor | Factor | 42 . ! 42 | Give a code snippet in #Factor
| christopher/rosetta-code | ||
http://rosettacode.org/wiki/Sorting_algorithms/Gnome_sort | Sorting algorithms/Gnome sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #SNOBOL4 | SNOBOL4 | *** GNOME SORT *****************************************************************
* GNOME(V) -- gnome sort of the numerical vector V.
*** HELPER FUNCTIONS ***********************************************************
* IDXMAX(V) -- highest index of vector V.
* IDXMIN(V) -- lowest index of vector V.
* NUMBER(V) --... | Give a code snippet in #SNOBOL4
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/Knuth_shuffle | Knuth shuffle | The Knuth shuffle (a.k.a. the Fisher-Yates shuffle) is an algorithm for randomly shuffling the elements of an array.
Task
Implement the Knuth shuffle for an integer array (or, if possible, an array of any type).
Specification
Given an array items with indices ranging from 0 to last, the algorithm can be d... | #Wren | Wren | import "random" for Random
var rand = Random.new()
var knuthShuffle = Fn.new { |a|
var i = a.count - 1
while (i >= 1) {
var j = rand.int(i + 1)
var t = a[i]
a[i] = a[j]
a[j] = t
i = i - 1
}
}
var tests = [ [], [10], [10, 20], [10, 20, 30] ]
for (a in tests) {
... | Give a code snippet in #Wren
The Knuth shuffle (a.k.a. the Fisher-Yates shuffle) is an algorithm for randomly shuffling the elements of an array.
Task
Implement the Knuth shuffle for an integer array (or, if possible, an array of any type).
Specification
Given an array items with indices ranging from 0 t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation | Horner's rule for polynomial evaluation | A fast scheme for evaluating a polynomial such as:
−
19
+
7
x
−
4
x
2
+
6
x
3
{\displaystyle -19+7x-4x^{2}+6x^{3}\,}
when
x
=
3
{\displaystyle x=3\;}
.
is to arrange the computation as follows:
(
(
(
(
0
)
x
+
6
)
x
+
(
−
4
)
)
x
+
7
)
x
+
(
−
19
)
{\displaystyle ((((0)x+6)x+(-4))x... | #C.23 | C# | using System;
using System.Linq;
class Program
{
static double Horner(double[] coefficients, double variable)
{
return coefficients.Reverse().Aggregate(
(accumulator, coefficient) => accumulator * variable + coefficient);
}
static void Main()
{
Console.WriteLine(H... | Give a code snippet in #C.23
A fast scheme for evaluating a polynomial such as:
−
19
+
7
x
−
4
x
2
+
6
x
3
{\displaystyle -19+7x-4x^{2}+6x^{3}\,}
when
x
=
3
{\displaystyle x=3\;}
.
is to arrange the computation as follows:
(
(
(
(
0
)
x
+
6
)
x
+
(
−
4
)
)
x
+
7
)
x
+
(
−
19
)
{\d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mayan_numerals | Mayan numerals | Task
Present numbers using the Mayan numbering system (displaying the Mayan numerals in a cartouche).
Mayan numbers
Normally, Mayan numbers are written vertically (top─to─bottom) with the most significant
numeral at the top (in the sense that decimal numbers are written left─to─right with the most signific... | #AppleScript | AppleScript | use AppleScript version "2.4"
use framework "Foundation"
use scripting additions
-- MAYAN NUMBERS ------------------------------------------
-- mayanNumber:: Int -> [[String]]
on mayanNumber(n)
showIntAtBase(20, my mayanDigit, n, {})
end mayanNumber
-- mayanDigit :: Int -> String
on mayanDigit(n)
if 0 < n... | Give a code snippet in #AppleScript
Task
Present numbers using the Mayan numbering system (displaying the Mayan numerals in a cartouche).
Mayan numbers
Normally, Mayan numbers are written vertically (top─to─bottom) with the most significant
numeral at the top (in the sense that decimal numbers are written... | christopher/rosetta-code | |
http://rosettacode.org/wiki/SHA-1 | SHA-1 | SHA-1 or SHA1 is a one-way hash function;
it computes a 160-bit message digest.
SHA-1 often appears in security protocols; for example,
many HTTPS websites use RSA with SHA-1 to secure their connections.
BitTorrent uses SHA-1 to verify downloads.
Git and Mercurial use SHA-1 digests to identify commits.
A US government... | #Elixir | Elixir |
iex(1)> :crypto.hash(:sha, "A string")
<<110, 185, 174, 8, 151, 66, 9, 104, 174, 225, 10, 43, 9, 92, 82, 190, 197, 150,
224, 92>>
| Give a code snippet in #Elixir
SHA-1 or SHA1 is a one-way hash function;
it computes a 160-bit message digest.
SHA-1 often appears in security protocols; for example,
many HTTPS websites use RSA with SHA-1 to secure their connections.
BitTorrent uses SHA-1 to verify downloads.
Git and Mercurial use SHA-1 digests to id... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nested_function | Nested function | In many languages, functions can be nested, resulting in outer functions and inner functions. The inner function can access variables from the outer function. In most languages, the inner function can also modify variables in the outer function.
Task
Write a program consisting of two nested functions that prints t... | #Sidef | Sidef | func make_list(separator = ') ') {
var count = 1
func make_item(item) {
[count++, separator, item].join
}
<first second third>.map(make_item).join("\n")
}
say make_list('. ') | Give a code snippet in #Sidef
In many languages, functions can be nested, resulting in outer functions and inner functions. The inner function can access variables from the outer function. In most languages, the inner function can also modify variables in the outer function.
Task
Write a program consisting of two... | christopher/rosetta-code | |
http://rosettacode.org/wiki/SQL-based_authentication | SQL-based authentication | This task has three parts:
Connect to a MySQL database (connect_db)
Create user/password records in the following table (create_user)
Authenticate login requests against the table (authenticate_user)
This is the table definition:
CREATE TABLE users (
userid INT PRIMARY KEY AUTO_INCREMENT,
username VARCHAR(... | #Phix | Phix | -- demo\rosetta\SQL-based_authentication.exw
without js -- (file i/o)
include pSQLite.e
include md5.exw
sqlite3_stmt pAddUser = NULL
procedure add_user(sqlite3 db, string name, pw)
if pAddUser=NULL then
pAddUser = sqlite3_prepare(db,"INSERT INTO users (username,pass_salt,pass_md5) VALUES(:name, :salt, :m... | Give a code snippet in #Phix
This task has three parts:
Connect to a MySQL database (connect_db)
Create user/password records in the following table (create_user)
Authenticate login requests against the table (authenticate_user)
This is the table definition:
CREATE TABLE users (
userid INT PRIMARY KEY AUTO_IN... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mayan_numerals | Mayan numerals | Task
Present numbers using the Mayan numbering system (displaying the Mayan numerals in a cartouche).
Mayan numbers
Normally, Mayan numbers are written vertically (top─to─bottom) with the most significant
numeral at the top (in the sense that decimal numbers are written left─to─right with the most signific... | #Go | Go | package main
import (
"fmt"
"strconv"
)
const (
ul = "╔"
uc = "╦"
ur = "╗"
ll = "╚"
lc = "╩"
lr = "╝"
hb = "═"
vb = "║"
)
var mayan = [5]string{
" ",
" ∙ ",
" ∙∙ ",
"∙∙∙ ",
"∙∙∙∙",
}
const (
m0 = " Θ "
m5 = "────"
)
func dec2vig(n uint64... | Give a code snippet in #Go
Task
Present numbers using the Mayan numbering system (displaying the Mayan numerals in a cartouche).
Mayan numbers
Normally, Mayan numbers are written vertically (top─to─bottom) with the most significant
numeral at the top (in the sense that decimal numbers are written left─to─... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Lah_numbers | Lah numbers | Lah numbers, sometimes referred to as Stirling numbers of the third kind, are coefficients of polynomial expansions expressing rising factorials in terms of falling factorials.
Unsigned Lah numbers count the number of ways a set of n elements can be partitioned into k non-empty linearly ordered subsets.
Lah numbers a... | #Prolog | Prolog | % Reference: https://en.wikipedia.org/wiki/Lah_number#Identities_and_relations
:- dynamic unsigned_lah_number_cache/3.
unsigned_lah_number(N, N, 1):-!.
unsigned_lah_number(_, 0, 0):-!.
unsigned_lah_number(N, K, 0):-
K > N,
!.
unsigned_lah_number(N, K, L):-
unsigned_lah_number_cache(N, K, L),
!.
unsigned_lah_num... | Give a code snippet in #Prolog
Lah numbers, sometimes referred to as Stirling numbers of the third kind, are coefficients of polynomial expansions expressing rising factorials in terms of falling factorials.
Unsigned Lah numbers count the number of ways a set of n elements can be partitioned into k non-empty linearly... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Factors_of_an_integer | Factors of an integer |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Relation | Relation |
program factors(num)
relation fact
insert 1
set i = 2
while i < num / 2
if num / i = floor(num/i)
insert i
end if
set i = i + 1
end while
insert num
print
end program
| Give a code snippet in #Relation
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/Top_rank_per_group | Top rank per group | Task
Find the top N salaries in each department, where N is provided as a parameter.
Use this data as a formatted internal data structure (adapt it to your language-native idioms, rather than parse at runtime), or identify your external data source:
Employee Name,Employee ID,Salary,Department
Tyler Bennett... | #Sidef | Sidef | var data = <<'EOF'.lines.map{ <name id salary dept> ~Z .split(',') -> flat.to_h }
Tyler Bennett,E10297,32000,D101
John Rappl,E21437,47000,D050
George Woltman,E00127,53500,D101
Adam Smith,E63535,18000,D202
Claire Buckman,E39876,27800,D202
David McClellan,E04242,41500,D101
Rich Holcomb,E01234,49500,D202
Nathan Adams,E412... | Give a code snippet in #Sidef
Task
Find the top N salaries in each department, where N is provided as a parameter.
Use this data as a formatted internal data structure (adapt it to your language-native idioms, rather than parse at runtime), or identify your external data source:
Employee Name,Employee ID,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Subleq | Subleq | Subleq is an example of a One-Instruction Set Computer (OISC).
It is named after its only instruction, which is SUbtract and Branch if Less than or EQual to zero.
Task
Your task is to create an interpreter which emulates a SUBLEQ machine.
The machine's memory consists of an array of signed integers. These integers... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | ClearAll[memory, MemoryGet, MemorySet, MemorySubtract]
memory = {15, 17, -1, 17, -1, -1, 16, 1, -1, 16, 3, -1, 15, 15, 0,
0, -1, 72, 101, 108, 108, 111, 44, 32, 119, 111, 114, 108, 100, 33,
10, 0};
MemoryGet[addr_] := memory[[addr + 1]]
MemorySet[addr_, value_] := memory[[addr + 1]] = value
MemorySubtract[addr1... | Give a code snippet in #Mathematica_.2F_Wolfram_Language
Subleq is an example of a One-Instruction Set Computer (OISC).
It is named after its only instruction, which is SUbtract and Branch if Less than or EQual to zero.
Task
Your task is to create an interpreter which emulates a SUBLEQ machine.
The machine's memory... | christopher/rosetta-code |
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