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/User_input/Graphical | User input/Graphical |
In this task, the goal is to input a string and the integer 75000, from graphical user interface.
See also: User input/Text
| #PicoLisp | PicoLisp | (and
(call 'sh "-c"
(pack
"dialog \
--inputbox 'Input a string' 8 60 \
--inputbox 'Input a number' 8 20 \
2>"
(tmp "dlg") ) )
(split (in (tmp "dlg") (line)) "^I")
(cons (pack (car @)) (format (cadr @))) ) | Give a code snippet in #PicoLisp
In this task, the goal is to input a string and the integer 75000, from graphical user interface.
See also: User input/Text
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Hailstone_sequence | Hailstone sequence | The Hailstone sequence of numbers can be generated from a starting positive integer, n by:
If n is 1 then the sequence ends.
If n is even then the next n of the sequence = n/2
If n is odd then the next n of the sequence = (3 * n) + 1
The (unproven) Collatz conje... | #ACL2 | ACL2 | (defun hailstone (len)
(loop for x = len
then (if (evenp x)
(/ x 2)
(+ 1 (* 3 x)))
collect x until (= x 1)))
;; Must be tail recursive
(defun max-hailstone-start (limit mx curr)
(declare (xargs :mode :program))
(if (zp limit)
... | Give a code snippet in #ACL2
The Hailstone sequence of numbers can be generated from a starting positive integer, n by:
If n is 1 then the sequence ends.
If n is even then the next n of the sequence = n/2
If n is odd then the next n of the sequence = (3 * n) + 1
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Downward_for | Loops/Downward for | Task
Write a for loop which writes a countdown from 10 to 0.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within loop body... | #Avail | Avail | For each i from 10 to 0 by -1 do [Print: “i” ++ "\n";]; | Give a code snippet in #Avail
Task
Write a for loop which writes a countdown from 10 to 0.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increm... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Letter_frequency | Letter frequency | Task
Open a text file and count the occurrences of each letter.
Some of these programs count all characters (including punctuation),
but some only count letters A to Z.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequen... | #IS-BASIC | IS-BASIC | 100 PROGRAM "Letters.bas"
110 NUMERIC LETT(65 TO 90)
120 FOR I=65 TO 90
130 LET LETT(I)=0
140 NEXT
150 LET EOF=0
160 OPEN #1:"list.txt"
170 WHEN EXCEPTION USE IOERROR
180 DO
190 GET #1:A$
200 LET A$=UCASE$(A$)
210 IF A$>="A" AND A$<="Z" THEN LET LETT(ORD(A$))=LETT(ORD(A$))+1
220 LOOP UNTIL EOF
230 END... | Give a code snippet in #IS-BASIC
Task
Open a text file and count the occurrences of each letter.
Some of these programs count all characters (including punctuation),
but some only count letters A to Z.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Monty_Hall_problem | Monty Hall problem |
Suppose you're on a game show and you're given the choice of three doors.
Behind one door is a car; behind the others, goats.
The car and the goats were placed randomly behind the doors before the show.
Rules of the game
After you have chosen a door, the door remains closed for the time being.
The game show hos... | #BBC_BASIC | BBC BASIC | total% = 10000
FOR trial% = 1 TO total%
prize_door% = RND(3) : REM. The prize is behind this door
guess_door% = RND(3) : REM. The contestant guesses this door
IF prize_door% = guess_door% THEN
REM. The contestant guessed right, reveal either of the others
reveal_d... | Give a code snippet in #BBC_BASIC
Suppose you're on a game show and you're given the choice of three doors.
Behind one door is a car; behind the others, goats.
The car and the goats were placed randomly behind the doors before the show.
Rules of the game
After you have chosen a door, the door remains closed for... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Perfect_shuffle | Perfect shuffle | A perfect shuffle (or faro/weave shuffle) means splitting a deck of cards into equal halves, and perfectly interleaving them - so that you end up with the first card from the left half, followed by the first card from the right half, and so on:
7♠ 8♠ 9♠ J♠ Q♠ K♠→7♠ 8♠ 9♠
J♠ Q♠ K♠→7♠ J♠ 8♠ Q♠ 9♠ K♠
When you ... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | shuffle[deck_] := Apply[Riffle, TakeDrop[deck, Length[deck]/2]];
shuffleCount[n_] := Block[{count=0}, NestWhile[shuffle, shuffle[Range[n]], (count++; OrderedQ[#] )&];count];
Map[shuffleCount, {8, 24, 52, 100, 1020, 1024, 10000}] | Give a code snippet in #Mathematica.2FWolfram_Language
A perfect shuffle (or faro/weave shuffle) means splitting a deck of cards into equal halves, and perfectly interleaving them - so that you end up with the first card from the left half, followed by the first card from the right half, and so on:
7♠ 8♠ 9♠ J♠ Q♠ ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Password_generator | Password generator | Create a password generation program which will generate passwords containing random ASCII characters from the following groups:
lower-case letters: a ──► z
upper-case letters: A ──► Z
digits: 0 ──► 9
other printable characters: !"#$%&'()*+,-./:;<=>?@[]^_{|}~
(the above ch... | #Kotlin | Kotlin | // version 1.1.4-3
import java.util.Random
import java.io.File
val r = Random()
val rr = Random() // use a separate generator for shuffles
val ls = System.getProperty("line.separator")
var lower = "abcdefghijklmnopqrstuvwxyz"
var upper = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
var digit = "0123456789"
var other = """!"#$%... | Give a code snippet in #Kotlin
Create a password generation program which will generate passwords containing random ASCII characters from the following groups:
lower-case letters: a ──► z
upper-case letters: A ──► Z
digits: 0 ──► 9
other printable characters: !"#$%&'()*+,-.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_occurrences_of_a_substring | Count occurrences of a substring | Task
Create a function, or show a built-in function, to count the number of non-overlapping occurrences of a substring inside a string.
The function should take two arguments:
the first argument being the string to search, and
the second a substring to be searched for.
It should return an integer cou... | #Groovy | Groovy | println (('the three truths' =~ /th/).count)
println (('ababababab' =~ /abab/).count)
println (('abaabba*bbaba*bbab' =~ /a*b/).count)
println (('abaabba*bbaba*bbab' =~ /a\*b/).count) | Give a code snippet in #Groovy
Task
Create a function, or show a built-in function, to count the number of non-overlapping occurrences of a substring inside a string.
The function should take two arguments:
the first argument being the string to search, and
the second a substring to be searched for.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Number_reversal_game | Number reversal game | Task
Given a jumbled list of the numbers 1 to 9 that are definitely not in
ascending order.
Show the list, and then ask the player how many digits from the
left to reverse.
Reverse those digits, then ask again, until all the digits end up in ascending order.
The score is the count of the reversa... | #Io | Io | withRange := method( a, z,
Range clone setRange(a,z)
)
sorted := withRange(1,9) asList
numbers := sorted clone shuffle
while( numbers==sorted, numbers = numbers shuffle)
steps :=0
stdin := File standardInput
while( numbers != sorted,
writeln(numbers join(" "))
write("Reverse how many? ")
flipcount :... | Give a code snippet in #Io
Task
Given a jumbled list of the numbers 1 to 9 that are definitely not in
ascending order.
Show the list, and then ask the player how many digits from the
left to reverse.
Reverse those digits, then ask again, until all the digits end up in ascending order.
The score... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Juggler_sequence | Juggler sequence | Background of the juggler sequence:
Juggler sequences were publicized by an American mathematician and author Clifford A. Pickover. The name of the sequence gets it's name from the similarity of the rising and falling nature of the numbers in the sequences, much like balls in the hands of a juggler.
Descrip... | #Ruby | Ruby | def juggler(k) = k.even? ? Integer.sqrt(k) : Integer.sqrt(k*k*k)
(20..39).chain([113, 173, 193, 2183, 11229, 15065, 15845, 30817, 48443, 275485, 1267909, 2264915]).each do |k|
k1 = k
l = h = i = 0
until k == 1 do
h, i = k, l if k > h
l += 1
k = juggler(k)
end
if k1 < 40 then
puts "#{k1}: l[... | Give a code snippet in #Ruby
Background of the juggler sequence:
Juggler sequences were publicized by an American mathematician and author Clifford A. Pickover. The name of the sequence gets it's name from the similarity of the rising and falling nature of the numbers in the sequences, much like balls in the ... | 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... | #Java | Java | public class MagicSquare {
public static void main(String[] args) {
int n = 5;
for (int[] row : magicSquareOdd(n)) {
for (int x : row)
System.out.format("%2s ", x);
System.out.println();
}
System.out.printf("\nMagic constant: %d ", (n * n + 1... | Give a code snippet in #Java
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Metronome | Metronome |
The task is to implement a metronome.
The metronome should be capable of producing high and low audio beats, accompanied by a visual beat indicator, and the beat pattern and tempo should be configurable.
For the purpose of this task, it is acceptable to play sound files for production of the beat notes, and an ext... | #Ada | Ada |
with Ada.Text_IO; use Ada.Text_IO;
--This package is for the delay.
with Ada.Calendar; use Ada.Calendar;
--This package adds sound
with Ada.Characters.Latin_1;
procedure Main is
begin
Put_Line ("Hello, this is 60 BPM");
loop
Ada.Text_IO.Put (Ada.Characters.Latin_1.BEL);
delay 0.9;... | Give a code snippet in #Ada
The task is to implement a metronome.
The metronome should be capable of producing high and low audio beats, accompanied by a visual beat indicator, and the beat pattern and tempo should be configurable.
For the purpose of this task, it is acceptable to play sound files for production ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/ISBN13_check_digit | ISBN13 check digit | Task
Validate the check digit of an ISBN-13 code:
Multiply every other digit by 3.
Add these numbers and the other digits.
Take the remainder of this number after division by 10.
If it is 0, the ISBN-13 check digit is correct.
Use the following codes for testing:
978-1734314502 (good)
... | #Modula-2 | Modula-2 | MODULE ISBN;
FROM InOut IMPORT WriteString, WriteLn;
FROM Strings IMPORT Length;
PROCEDURE validISBN(s: ARRAY OF CHAR): BOOLEAN;
VAR total, i, length: CARDINAL;
BEGIN
total := 0;
length := Length(s);
IF (length # 14) OR (s[3] # '-') THEN
RETURN FALSE;
END;
FOR i := 0 TO length-1 DO
... | Give a code snippet in #Modula-2
Task
Validate the check digit of an ISBN-13 code:
Multiply every other digit by 3.
Add these numbers and the other digits.
Take the remainder of this number after division by 10.
If it is 0, the ISBN-13 check digit is correct.
Use the following codes for testing:
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #Tcl | Tcl | proc div_check {x y} {
if {[catch {expr {$x/$y}} result] == 0} {
puts "valid division: $x/$y=$result"
} else {
if {$result eq "divide by zero"} {
puts "caught division by zero: $x/$y -> $result"
} else {
puts "caught another error: $x/$y -> $result"
}
... | Give a code snippet in #Tcl
Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_subsequential_sum | Greatest subsequential sum | Task
Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one.
An empty subsequence is considered to have the sum of 0; thus if all elements are negative, the result must be th... | #C | C | #include "stdio.h"
typedef struct Range {
int start, end, sum;
} Range;
Range maxSubseq(const int sequence[], const int len) {
int maxSum = 0, thisSum = 0, i = 0;
int start = 0, end = -1, j;
for (j = 0; j < len; j++) {
thisSum += sequence[j];
if (thisSum < 0) {
i = j + ... | Give a code snippet in #C
Task
Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one.
An empty subsequence is considered to have the sum of 0; thus if all elements are nega... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Inheritance/Single | Inheritance/Single | This task is about derived types; for implementation inheritance, see Polymorphism.
Inheritance is an operation of type algebra that creates a new type from one or several parent types.
The obtained type is called derived type.
It inherits some of the properties of its parent types.
Usually inherited properties... | #Raku | Raku | class Animal {}
class Dog is Animal {}
class Cat is Animal {}
class Lab is Dog {}
class Collie is Dog {}
say Collie.^parents; # undefined type object
say Collie.new.^parents; # instantiated object | Give a code snippet in #Raku
This task is about derived types; for implementation inheritance, see Polymorphism.
Inheritance is an operation of type algebra that creates a new type from one or several parent types.
The obtained type is called derived type.
It inherits some of the properties of its parent types.... | 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 ... | #FreeBASIC | FreeBASIC | #define NAN 0.0/0.0 'dot product of different-dimensioned vectors is no more defined than 0/0
function dot( a() as double, b() as double ) as double
if ubound(a)<>ubound(b) then return NAN
dim as uinteger i
dim as double dp = 0.0
for i = 0 to ubound(a)
dp += a(i)*b(i)
next i
retur... | Give a code snippet in #FreeBASIC
Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Median | Averages/Median | Task[edit]
Write a program to find the median value of a vector of floating-point numbers.
The program need not handle the case where the vector is empty, but must handle the case where there are an even number of elements. In that case, return the average of the two middle values.
There are several approaches ... | #SenseTalk | SenseTalk | put the median of [4.1, 5.6, 7.2, 1.7, 9.3, 4.4, 3.2]
put the median of [4.1, 5.6, 7.2, 1.7, 9.3, 4.4, 3.2, 6.6]
put customMedian of [4.1, 5.6, 7.2, 1.7, 9.3, 4.4, 3.2]
put customMedian of [4.1, 5.6, 7.2, 1.7, 9.3, 4.4, 3.2, 6.6]
to handle customMedian of list
sort list
if the number of items in list is an even n... | Give a code snippet in #SenseTalk
Task[edit]
Write a program to find the median value of a vector of floating-point numbers.
The program need not handle the case where the vector is empty, but must handle the case where there are an even number of elements. In that case, return the average of the two middle val... | 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.
... | #XPL0 | XPL0 | real B1, B2, Ang;
[Text(0, " Bearing 1 Bearing 2 Difference");
loop [B1:= RlIn(1);
B2:= RlIn(1);
Ang:= B2 - B1;
while Ang > 180. do Ang:= Ang - 360.;
while Ang < -180. do Ang:= Ang + 360.;
CrLf(0);
RlOut(0, B1); ChOut(0, 9);
RlOut(0, B2); ChOu... | Give a code snippet in #XPL0
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/Julia_set | Julia set |
Task
Generate and draw a Julia set.
Related tasks
Mandelbrot Set
| #F.23 | F# |
let getJuliaValues width height centerX centerY zoom maxIter =
let initzx x = 1.5 * float(x - width/2) / (0.5 * zoom * float(width))
let initzy y = 1.0 * float(y - height/2) / (0.5 * zoom * float(height))
let calc y x =
let rec loop i zx zy =
if i=maxIter then 0
elif zx*zx + zy*zy >= 4.0 then i
... | Give a code snippet in #F.23
Task
Generate and draw a Julia set.
Related tasks
Mandelbrot Set
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #Visual_Basic_.NET | Visual Basic .NET | Console.WriteLine(Chr(97)) 'Prints a
Console.WriteLine(Asc("a")) 'Prints 97 | Give a code snippet in #Visual_Basic_.NET
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Uni... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/While | Loops/While | Task
Start an integer value at 1024.
Loop while it is greater than zero.
Print the value (with a newline) and divide it by two each time through the loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For... | #Elixir | Elixir | defmodule Loops do
def while(0), do: :ok
def while(n) do
IO.puts n
while( div(n,2) )
end
end
Loops.while(1024) | Give a code snippet in #Elixir
Task
Start an integer value at 1024.
Loop while it is greater than zero.
Print the value (with a newline) and divide it by two each time through the loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downwa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Program_termination | Program termination |
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks... | #Gema | Gema | Star Trek=@err{found a Star Trek reference\n}@abort | Give a code snippet in #Gema
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/... | 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... | #Plain_English | Plain English | Put "abcdef" into a string.
Slap a rider on the string. | Give a code snippet in #Plain_English
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 clearl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ... | #Elena | Elena | import extensions;
fibu(n)
{
int[] ac := new int[]{ 0,1 };
if (n < 2)
{
^ ac[n]
}
else
{
for(int i := 2, i <= n, i+=1)
{
int t := ac[1];
ac[1] := ac[0] + ac[1];
ac[0] := t
};
^ ac[1]
}
}
public program()
{
... | Give a code snippet in #Elena
The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are... | christopher/rosetta-code | |
http://rosettacode.org/wiki/The_Twelve_Days_of_Christmas | The Twelve Days of Christmas | Task
Write a program that outputs the lyrics of the Christmas carol The Twelve Days of Christmas.
The lyrics can be found here.
(You must reproduce the words in the correct order, but case, format, and punctuation are left to your discretion.)
Other tasks related to string operations:
Metrics
Array length
Stri... | #PHP | PHP |
<?php
header("Content-Type: text/plain; charset=UTF-8");
$days = array(
'first', 'second', 'third', 'fourth', 'fifth', 'sixth', 'seventh', 'eighth', 'ninth',
'tenth', 'eleventh', 'twelfth',
);
$gifts = array(
"A partridge in a pear tree",
"Two turtle doves",
"Three french hens",
"Four ca... | Give a code snippet in #PHP
Task
Write a program that outputs the lyrics of the Christmas carol The Twelve Days of Christmas.
The lyrics can be found here.
(You must reproduce the words in the correct order, but case, format, and punctuation are left to your discretion.)
Other tasks related to string operations:... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multiple_distinct_objects | Multiple distinct objects | Create a sequence (array, list, whatever) consisting of n distinct, initialized items of the same type. n should be determined at runtime.
By distinct we mean that if they are mutable, changes to one do not affect all others; if there is an appropriate equality operator they are considered unequal; etc. The code need ... | #M2000_Interpreter | M2000 Interpreter |
Module CheckIt {
Form 60, 40
Foo=Lambda Id=1 (m)->{
class Alfa {
x, id
Class:
Module Alfa(.x, .id) {}
}
=Alfa(m, id)
id++
}
Dim A(10)<<Foo(20)
\\ for each arrayitem call Foo(20)
... | Give a code snippet in #M2000_Interpreter
Create a sequence (array, list, whatever) consisting of n distinct, initialized items of the same type. n should be determined at runtime.
By distinct we mean that if they are mutable, changes to one do not affect all others; if there is an appropriate equality operator they ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Validate_International_Securities_Identification_Number | Validate International Securities Identification Number | An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond.
Task
Write a function or program that takes a string as input, and checks whether it is a valid ISIN.
It is only valid if it has the correct format, and the embedded c... | #Haskell | Haskell | module ISINVerification2 where
import Data.Char (isUpper, isDigit, digitToInt)
verifyISIN :: String -> Bool
verifyISIN isin =
correctFormat isin && mod (oddsum + multiplied_even_sum) 10 == 0
where
reverted = reverse $ convertToNumber isin
theOdds = fst $ collectOddandEven reverted
theEvens = snd $ c... | Give a code snippet in #Haskell
An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond.
Task
Write a function or program that takes a string as input, and checks whether it is a valid ISIN.
It is only valid if it has the corre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stable_marriage_problem | Stable marriage problem | Solve the Stable marriage problem using the Gale/Shapley algorithm.
Problem description
Given an equal number of men and women to be paired for marriage, each man ranks all the women in order of his preference and each woman ranks all the men in order of her preference.
A stable set of engagements for marriage is o... | #Wren | Wren | import "/dynamic" for Struct
var mPref = {
"abe": [
"abi", "eve", "cath", "ivy", "jan",
"dee", "fay", "bea", "hope", "gay"],
"bob": [
"cath", "hope", "abi", "dee", "eve",
"fay", "bea", "jan", "ivy", "gay"],
"col": [
"hope", "eve", "abi", "dee", "bea",
"fay",... | Give a code snippet in #Wren
Solve the Stable marriage problem using the Gale/Shapley algorithm.
Problem description
Given an equal number of men and women to be paired for marriage, each man ranks all the women in order of his preference and each woman ranks all the men in order of her preference.
A stable set of... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Doubly-linked_list/Element_definition | Doubly-linked list/Element definition | Task
Define the data structure for a doubly-linked list element.
The element should include a data member to hold its value and pointers to both the next element in the list and the previous element in the list.
The pointers should be mutable.
See also
Array
Associative array: Creation, Iteration
Collections
... | #Oz | Oz | fun {CreateNewNode Value}
node(prev:{NewCell _}
next:{NewCell _}
value:Value)
end | Give a code snippet in #Oz
Task
Define the data structure for a doubly-linked list element.
The element should include a data member to hold its value and pointers to both the next element in the list and the previous element in the list.
The pointers should be mutable.
See also
Array
Associative array: Creat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fork | Fork | Task
Spawn a new process which can run simultaneously with, and independently of, the original parent process.
| #Symsyn | Symsyn |
| parent
ssx 'R child'
wait 'childevent'
'child is running...' []
'child will end...' []
post 'dieevent'
delay 5000
| Give a code snippet in #Symsyn
Task
Spawn a new process which can run simultaneously with, and independently of, the original parent process.
| 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... | #Lua | Lua | num_iterations = 9
f = { 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0 }
function Output( f, l )
io.write( l, ": " )
for i = 1, #f do
local c
if f[i] == 1 then c = '#' else c = '_' end
io.write( c )
end
print ""
end
Output( f, 0 )
for l = 1, num_iterations do
... | Give a code snippet in #Lua
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 g... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Van_Eck_sequence | Van Eck sequence | The sequence is generated by following this pseudo-code:
A: The first term is zero.
Repeatedly apply:
If the last term is *new* to the sequence so far then:
B: The next term is zero.
Otherwise:
C: The next term is how far back this last term occured previously.
Example
Using ... | #BASIC | BASIC | 10 DEFINT A-Z
20 DIM E(1000)
30 FOR I=0 TO 999
40 FOR J=I-1 TO 0 STEP -1
50 IF E(J)=E(I) THEN E(I+1)=I-J: GOTO 80
60 NEXT J
70 E(I+1)=0
80 NEXT I
90 FOR I=0 TO 9: PRINT E(I);: NEXT
95 PRINT
100 FOR I=990 TO 999: PRINT E(I);: NEXT | Give a code snippet in #BASIC
The sequence is generated by following this pseudo-code:
A: The first term is zero.
Repeatedly apply:
If the last term is *new* to the sequence so far then:
B: The next term is zero.
Otherwise:
C: The next term is how far back this last term occured... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Image_noise | Image noise | Generate a random black and white 320x240 image continuously,
showing FPS (frames per second).
A sample image
| #D | D | import std.stdio, std.random, sdl.SDL;
void main() {
SDL_Init(SDL_INIT_TIMER | SDL_INIT_VIDEO);
auto surface = SDL_SetVideoMode(320,240,8, SDL_DOUBLEBUF|SDL_HWSURFACE);
uint frameNumber, totalTime, lastTime;
while (true) {
SDL_LockSurface(surface);
foreach (i; 0 .. surface.w * surface.h)
(cast... | Give a code snippet in #D
Generate a random black and white 320x240 image continuously,
showing FPS (frames per second).
A sample image
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Holidays_related_to_Easter | Holidays related to Easter | Task
Calculate the dates of:
Easter
Ascension Thursday
Pentecost
Trinity Sunday
Corpus Christi feast (for Catholic)
All Saints' Sunday (for Orthodox)
As an example, calculate for the first year of each century from;
years 400 to 2100 CE and for
years 2010 to 2020 CE.
Note
... | #C | C | #include <stdio.h>
typedef int year_t, month_t, week_t, day_t;
typedef struct{
year_t year; /* day_t year_day, */
month_t month; day_t month_day;/*
week_t week, */ day_t week_day; } date_t;
const char *mon_fmt[] = {0, "Jan", "Feb", "Mar", "Apr", "May", "Jun",
"Jul", "Aug", ... | Give a code snippet in #C
Task
Calculate the dates of:
Easter
Ascension Thursday
Pentecost
Trinity Sunday
Corpus Christi feast (for Catholic)
All Saints' Sunday (for Orthodox)
As an example, calculate for the first year of each century from;
years 400 to 2100 CE and for
years ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/CRC-32 | CRC-32 |
Task
Demonstrate a method of deriving the Cyclic Redundancy Check from within the language.
The result should be in accordance with ISO 3309, ITU-T V.42, Gzip and PNG.
Algorithms are described on Computation of CRC in Wikipedia.
This variant of CRC-32 uses LSB-first order, sets the initial CRC to FFFFFFFF16, and... | #Forth | Forth |
: crc/ ( n -- n ) 8 0 do dup 1 rshift swap 1 and if $edb88320 xor then loop ;
: crcfill 256 0 do i crc/ , loop ;
create crctbl crcfill
: crc+ ( crc n -- crc' ) over xor $ff and cells crctbl + @ swap 8 rshift xor ;
: crcbuf ( crc str len -- crc ) bounds ?do i c@ crc+ loop ;
$ffffffff s" The quick brown f... | Give a code snippet in #Forth
Task
Demonstrate a method of deriving the Cyclic Redundancy Check from within the language.
The result should be in accordance with ISO 3309, ITU-T V.42, Gzip and PNG.
Algorithms are described on Computation of CRC in Wikipedia.
This variant of CRC-32 uses LSB-first order, sets the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Median_filter | Median filter | The median filter takes in the neighbourhood the median color (see Median filter)
(to test the function below, you can use these input and output solutions)
| #Python | Python | import Image, ImageFilter
im = Image.open('image.ppm')
median = im.filter(ImageFilter.MedianFilter(3))
median.save('image2.ppm') | Give a code snippet in #Python
The median filter takes in the neighbourhood the median color (see Median filter)
(to test the function below, you can use these input and output solutions)
| 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... | #Eiffel | Eiffel | class
APPLICATION
create
make
feature {NONE} -- Initialization
make
local
numbers: ARRAY [STRING]
do
numbers := <<"MCMXC", "MMVIII", "MDCLXVI",
-- 1990 2008 1666
"MMMCLIX", "MCMLXXVII", "MMX">>
-- 3159 1977 2010
across numbers as ... | Give a code snippet in #Eiffel
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/Send_email | Send email | Task
Write a function to send an email.
The function should have parameters for setting From, To and Cc addresses; the Subject, and the message text, and optionally fields for the server name and login details.
If appropriate, explain what notifications of problems/success are given.
Solutions using libraries or f... | #Python | Python | import smtplib
def sendemail(from_addr, to_addr_list, cc_addr_list,
subject, message,
login, password,
smtpserver='smtp.gmail.com:587'):
header = 'From: %s\n' % from_addr
header += 'To: %s\n' % ','.join(to_addr_list)
header += 'Cc: %s\n' % ','.join(cc_addr_list)
... | Give a code snippet in #Python
Task
Write a function to send an email.
The function should have parameters for setting From, To and Cc addresses; the Subject, and the message text, and optionally fields for the server name and login details.
If appropriate, explain what notifications of problems/success are given.... | 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
... | #Seed7 | Seed7 | $ include "seed7_05.s7i";
const type: combinations is array array integer;
const func combinations: comb (in array integer: arr, in integer: k) is func
result
var combinations: combResult is combinations.value;
local
var integer: x is 0;
var integer: i is 0;
var array integer: suffix is 0 times ... | Give a code snippet in #Seed7
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Text_processing/1 | Text processing/1 | This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect once this task has been clarified. See this page's Talk page for discussion.
Often data is produced by one program, in the wrong format for later use by another program or person. In these situations another pr... | #C.2B.2B | C++ | #include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <iomanip>
#include <boost/lexical_cast.hpp>
#include <boost/algorithm/string.hpp>
using std::cout;
using std::endl;
const int NumFlags = 24;
int main()
{
std::fstream file("readings.txt");
int badCount = 0;
std::string... | Give a code snippet in #C.2B.2B
This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect once this task has been clarified. See this page's Talk page for discussion.
Often data is produced by one program, in the wrong format for later use by another program or perso... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Singly-linked_list/Traversal | Singly-linked list/Traversal | Traverse from the beginning of a singly-linked list to the end.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked ... | #Peloton | Peloton | <@ LETCNSLSTLIT>public holidays|開國紀念日^和平紀念日^婦女節、兒童節合併假期^清明節^國慶日^春節^端午節^中秋節^農曆除夕</@>
<@ OMT>From First to Last</@>
<@ ITEFORSZELSTLIT>public holidays|
<@ SAYLST>...</@><@ ACTMOVFWDLST>...</@>
</@>
<@ OMT>From Last to First (pointer is still at end of list)</@>
<@ ITEFORSZELSTLIT>public holidays|
<@ SAYLST>...</@><@ ACTM... | Give a code snippet in #Peloton
Traverse from the beginning of a singly-linked list to the end.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Defin... | 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... | #SQL_PL | SQL PL |
SET SERVEROUTPUT ON @
BEGIN
DECLARE NMBR VARCHAR(100) DEFAULT '1';
DECLARE J SMALLINT DEFAULT 1;
CALL DBMS_OUTPUT.PUT_LINE(NMBR);
WHILE (J < 10) DO
BEGIN
DECLARE I SMALLINT;
DECLARE SIZE SMALLINT;
DECLARE ACTUAL CHAR(1);
DECLARE REPEAT CHAR(1);
DECLARE RESULT VARCHAR(100);
DECLARE TIMES SMALLINT... | Give a code snippet in #SQL_PL
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 sequenc... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Write_language_name_in_3D_ASCII | Write language name in 3D ASCII | Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| #Haskell | Haskell | module Main where
{-
__ __ __ ___ ___
/\ \/\ \ /\ \ /\_ \ /\_ \
\ \ \_\ \ __ ____\ \ \/'\ __\//\ \ \//\ \
\ \ _ \ /'__`\ /',__\\ \ , < /'__`\\ \ \ \ \ \
\ \ \ \ \/\ \L\.\_/\__, `\\ \ \\`\ /\ __/ \_\ \_ \_\ \_
\ \_\ \_\ \__/.... | Give a code snippet in #Haskell
Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_elements_below_main_diagonal_of_matrix | Sum of elements below main diagonal of matrix | Task
Find and display the sum of elements that are below the main diagonal of a matrix.
The matrix should be a square matrix.
─── Matrix to be used: ───
[[1,3,7,8,10],
[2,4,16,14,4],
[3,1,9,18,11],
[12,14,17,18,20],
[7,1,3,9,5]]
| #C | C |
#include<stdlib.h>
#include<stdio.h>
typedef struct{
int rows,cols;
int** dataSet;
}matrix;
matrix readMatrix(char* dataFile){
FILE* fp = fopen(dataFile,"r");
matrix rosetta;
int i,j;
fscanf(fp,"%d%d",&rosetta.rows,&rosetta.cols);
rosetta.dataSet = (int**)malloc(rosetta.rows*sizeof(int*));
for(i=0;i... | Give a code snippet in #C
Task
Find and display the sum of elements that are below the main diagonal of a matrix.
The matrix should be a square matrix.
─── Matrix to be used: ───
[[1,3,7,8,10],
[2,4,16,14,4],
[3,1,9,18,11],
[12,14,17,18,20],
[7,1,3,9,5]]
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Comb_sort | Sorting algorithms/Comb sort | Sorting algorithms/Comb sort
You are encouraged to solve this task according to the task description, using any language you may know.
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 algor... | #360_Assembly | 360 Assembly | * Comb sort 23/06/2016
COMBSORT CSECT
USING COMBSORT,R13 base register
B 72(R15) skip savearea
DC 17F'0' savearea
STM R14,R12,12(R13) prolog
ST R13,4(R15) "
ST R15,8(R13) "
... | Give a code snippet in #360_Assembly
Sorting algorithms/Comb sort
You are encouraged to solve this task according to the task description, using any language you may know.
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 co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Summarize_and_say_sequence | Summarize and say sequence | There are several ways to generate a self-referential sequence. One very common one (the Look-and-say sequence) is to start with a positive integer, then generate the next term by concatenating enumerated groups of adjacent alike digits:
0, 10, 1110, 3110, 132110, 1113122110, 311311222110 ...
The terms generat... | #TXR | TXR | ;; Syntactic sugar for calling reduce-left
(defmacro reduce-with ((acc init item sequence) . body)
^(reduce-left (lambda (,acc ,item) ,*body) ,sequence ,init))
;; Macro similar to clojure's ->> and ->
(defmacro opchain (val . ops)
^[[chain ,*[mapcar [iffi consp (op cons 'op)] ops]] ,val])
;; Reduce integer to ... | Give a code snippet in #TXR
There are several ways to generate a self-referential sequence. One very common one (the Look-and-say sequence) is to start with a positive integer, then generate the next term by concatenating enumerated groups of adjacent alike digits:
0, 10, 1110, 3110, 132110, 1113122110, 311311... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Search_a_list_of_records | Search a list of records | Many programming languages provide convenient ways to look for a known value in a simple list of strings or numbers.
But what if the elements of the list are themselves compound records/objects/data-structures, and the search condition is more complex than a simple equality test?
Task[edit]
Write a function/method/et... | #Fortran | Fortran | MODULE SEMPERNOVIS !Keep it together.
TYPE CITYSTAT !Define a compound data type.
CHARACTER*28 NAME !Long enough?
REAL POPULATION !Accurate enough.
END TYPE CITYSTAT !Just two parts, but different types.
TYPE(CITYSTAT) CITY(10) !Righto, I'll have some.
DATA CITY/ !S... | Give a code snippet in #Fortran
Many programming languages provide convenient ways to look for a known value in a simple list of strings or numbers.
But what if the elements of the list are themselves compound records/objects/data-structures, and the search condition is more complex than a simple equality test?
Task... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_append | String append |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #JavaScript | JavaScript | var s1 = "Hello";
s1 += ", World!";
print(s1);
var s2 = "Goodbye";
// concat() returns the strings together, but doesn't edit existing string
// concat can also have multiple parameters
print(s2.concat(", World!")); | Give a code snippet in #JavaScript
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 Operat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Semiprime | Semiprime | Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers.
Semiprimes are also known as:
semi-primes
biprimes
bi-primes
2-almost primes
or simply: P2
Example
1679 = 23 × 73
(This particular number was chosen as the length of the Arecib... | #Rust | Rust | extern crate primal;
fn isqrt(n: usize) -> usize {
(n as f64).sqrt() as usize
}
fn is_semiprime(mut n: usize) -> bool {
let root = isqrt(n) + 1;
let primes1 = primal::Sieve::new(root);
let mut count = 0;
for i in primes1.primes_from(2).take_while(|&x| x < root) {
while n % i == 0 {
... | Give a code snippet in #Rust
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers.
Semiprimes are also known as:
semi-primes
biprimes
bi-primes
2-almost primes
or simply: P2
Example
1679 = 23 × 73
(This particular number was chos... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Polymorphism | Polymorphism | Task
Create two classes Point(x,y) and Circle(x,y,r) with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
| #EchoLisp | EchoLisp |
(struct Point ((real:x 0) (real:y 0)))
(struct Circle ((real:x 0) (real:y 0) (real:r 1)))
(define-method (print Point:p) (printf "📌 [%d %d]" p.x p.y))
(define-method (print Circle:c) (printf "⭕️ center:[%d %d] radius:%d" c.x c.y c.r))
(print (Point 5 6))
→ 📌 [5 6]
(print (Circle 2 3 4))
→ ⭕️ center:[2 3... | Give a code snippet in #EchoLisp
Task
Create two classes Point(x,y) and Circle(x,y,r) with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Stern-Brocot_sequence | Stern-Brocot sequence | For this task, the Stern-Brocot sequence is to be generated by an algorithm similar to that employed in generating the Fibonacci sequence.
The first and second members of the sequence are both 1:
1, 1
Start by considering the second member of the sequence
Sum the considered member of the sequence and its prece... | #Tcl | Tcl |
#!/usr/bin/env tclsh
#
package require generator ;# from tcllib
namespace eval stern-brocot {
proc generate {{count 100}} {
set seq {1 1}
set n 0
while {[llength $seq] < $count} {
lassign [lrange $seq $n $n+1] a b
lappend seq [expr {$a + $b}] $b
in... | Give a code snippet in #Tcl
For this task, the Stern-Brocot sequence is to be generated by an algorithm similar to that employed in generating the Fibonacci sequence.
The first and second members of the sequence are both 1:
1, 1
Start by considering the second member of the sequence
Sum the considered member ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Date_manipulation | Date manipulation | Task
Given the date string "March 7 2009 7:30pm EST",
output the time 12 hours later in any human-readable format.
As extra credit, display the resulting time in a time zone different from your own.
| #UNIX_Shell | UNIX Shell | epoch=$(date -d 'March 7 2009 7:30pm EST +12 hours' +%s)
date -d @$epoch
TZ=Asia/Shanghai date -d @$epoch | Give a code snippet in #UNIX_Shell
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/Mutual_recursion | Mutual recursion | Two functions are said to be mutually recursive if the first calls the second,
and in turn the second calls the first.
Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as:
F
(
0
)
=
1
;
M
(
0
)
=
0
F
(
n
)
=
n
−
M
(
F
(
n
−
1
)
)
,
... | #Euphoria | Euphoria | integer idM, idF
function F(integer n)
if n = 0 then
return 1
else
return n - call_func(idM,{F(n-1)})
end if
end function
idF = routine_id("F")
function M(integer n)
if n = 0 then
return 0
else
return n - call_func(idF,{M(n-1)})
end if
end function
idM = r... | Give a code snippet in #Euphoria
Two functions are said to be mutually recursive if the first calls the second,
and in turn the second calls the first.
Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as:
F
(
0
)
=
1
;
M
(
0
)
=
0
F
(... | 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... | #zkl | zkl | "http%3A%2F%2Ffoo%20bar%2F".pump(String, // push each char through these fcns:
fcn(c){ if(c=="%") return(Void.Read,2); return(Void.Skip,c) },// %-->read 2 chars else pass through
fcn(_,b,c){ (b+c).toInt(16).toChar() }) // "%" (ignored) "3"+"1"-->0x31-->"1" | Give a code snippet in #zkl
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/100_doors | 100 doors | There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #6, ...), and toggle it.
The third... | #ALGOL_68 | ALGOL 68 | # declare some constants #
INT limit = 100;
PROC doors = VOID:
(
MODE DOORSTATE = BOOL;
BOOL closed = FALSE;
BOOL open = NOT closed;
MODE DOORLIST = [limit]DOORSTATE;
DOORLIST the doors;
FOR i FROM LWB the doors TO UPB the doors DO the doors[i]:=closed OD;
FOR i FROM LWB the doors TO UPB the doors D... | Give a code snippet in #ALGOL_68
There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #6,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Truncate_a_file | Truncate a file | Task
Truncate a file to a specific length. This should be implemented as a routine that takes two parameters: the filename and the required file length (in bytes).
Truncation can be achieved using system or library calls intended for such a task, if such methods exist, or by creating a temporary file of a reduced... | #11l | 11l | F truncate_file(name, length)
I !fs:is_file(name)
R 0B
I length >= fs:file_size(name)
R 0B
fs:resize_file(name, length)
R 1B | Give a code snippet in #11l
Task
Truncate a file to a specific length. This should be implemented as a routine that takes two parameters: the filename and the required file length (in bytes).
Truncation can be achieved using system or library calls intended for such a task, if such methods exist, or by creating ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Grayscale_image | Grayscale image | Many image processing algorithms are defined for grayscale (or else monochromatic) images.
Task
Extend the data storage type defined on this page to support grayscale images.
Define two operations, one to convert a color image to a grayscale image and one for the backward conversion.
To get luminance of a color u... | #Python | Python | # String masquerading as ppm file (version P3)
import io
ppmfileout = io.StringIO('')
def togreyscale(self):
for h in range(self.height):
for w in range(self.width):
r, g, b = self.get(w, h)
l = int(0.2126 * r + 0.7152 * g + 0.0722 * b)
self.set(w, h, Colour(l, l, l))
... | Give a code snippet in #Python
Many image processing algorithms are defined for grayscale (or else monochromatic) images.
Task
Extend the data storage type defined on this page to support grayscale images.
Define two operations, one to convert a color image to a grayscale image and one for the backward conversion... | christopher/rosetta-code | |
http://rosettacode.org/wiki/IBAN | IBAN |
This page uses content from Wikipedia. The original article was at IBAN. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
The International Bank Account Number (IBAN) is an internationally agree... | #PHP | PHP |
<?php
function piece_wise($iban_all_digits) {
$remainder = NULL;
$slice = 9;
for ($i=0; $i<strlen($iban_all_digits); $i=$i+$slice)
{
if ($i>0)
{
$slice = 7;
}
$part = $remainder . substr($iban_all_digits, $i, $slice);
//echo "REMAINDER: " .... | Give a code snippet in #PHP
This page uses content from Wikipedia. The original article was at IBAN. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
The International Bank Account Number (IBAN) ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Flipping_bits_game | Flipping bits game | The game
Given an N×N square array of zeroes or ones in an initial configuration, and a target configuration of zeroes and ones.
The game is to transform one to the other in as few moves as possible by inverting whole numbered rows or whole lettered
columns at once (as one move).
In an inversion. any 1 ... | #Go | Go | package main
import (
"fmt"
"math/rand"
"time"
)
func main() {
rand.Seed(time.Now().UnixNano())
var n int = 3 // Change to define board size
var moves int = 0
a := make([][]int, n)
for i := range a {
a[i] = make([]int, n)
for j := range a {
a[i][j] = rand.Intn(2)
}
}
b := make([][]int,... | Give a code snippet in #Go
The game
Given an N×N square array of zeroes or ones in an initial configuration, and a target configuration of zeroes and ones.
The game is to transform one to the other in as few moves as possible by inverting whole numbered rows or whole lettered
columns at once (as one move).... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Taxicab_numbers | Taxicab numbers |
A taxicab number (the definition that is being used here) is a positive integer that can be expressed as the sum of two positive cubes in more than one way.
The first taxicab number is 1729, which is:
13 + 123 and also
93 + 103.
Taxicab numbers are also known as:
taxi numbers
tax... | #Clojure | Clojure | (ns test-project-intellij.core
(:gen-class))
(defn cube [x]
"Cube a number through triple multiplication"
(* x x x))
(defn sum3 [[i j]]
" [i j] -> i^3 + j^3"
(+ (cube i) (cube j)))
(defn next-pair [[i j]]
" Generate next [i j] pair of sequence (producing lower triangle pairs) "
(if (< j i)
[i ... | Give a code snippet in #Clojure
A taxicab number (the definition that is being used here) is a positive integer that can be expressed as the sum of two positive cubes in more than one way.
The first taxicab number is 1729, which is:
13 + 123 and also
93 + 103.
Taxicab numbers are also ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Pythagorean_means | Averages/Pythagorean means | Task[edit]
Compute all three of the Pythagorean means of the set of integers 1 through 10 (inclusive).
Show that
A
(
x
1
,
…
,
x
n
)
≥
G
(
x
1
,
…
,
x
n
)
≥
H
(
x
1
,
…
,
x
n
)
{\displaystyle A(x_{1},\ldots ,x_{n})\geq G(x_{1},\ldots ,x_{n})\geq H(x_{1},\ldots ,x_{n})}
for this set of p... | #PostScript | PostScript |
/pythamean{
/x exch def
/sum 0 def
/prod 1 def
/invsum 0 def
/i 1 def
x{
/sum sum i add def
/prod prod i mul def
/invsum invsum i -1 exp add def
/i i 1 add def
}repeat
(Arithmetic Mean : ) print
sum x div =
(Geometric Mean : ) print
prod x -1 exp exp =
(Harmonic Mean : ) print
x invsum div =
}def
10 pythamean
| Give a code snippet in #PostScript
Task[edit]
Compute all three of the Pythagorean means of the set of integers 1 through 10 (inclusive).
Show that
A
(
x
1
,
…
,
x
n
)
≥
G
(
x
1
,
…
,
x
n
)
≥
H
(
x
1
,
…
,
x
n
)
{\displaystyle A(x_{1},\ldots ,x_{n})\geq G(x_{1},\ldots ,x_{n})\geq H(x_{1}... | 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,... | #Octave | Octave | % test a bit; lsb is 1 (like built-in bit* ops)
function b = bittst(n, p)
b = bitand(n, 2^(p-1)) > 0;
endfunction
function f = Mfactor(p)
% msb is the index of the first non-zero bit
[b, msb] = max(bitand(p, 2 .^ [32:-1:1]) > 0);
maxk = floor(sqrt(intmax()) / p);
for k = 1 : maxk
q = 2*p*k + 1;
if ... | Give a code snippet in #Octave
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Total_circles_area | Total circles area | Total circles area
You are encouraged to solve this task according to the task description, using any language you may know.
Example circles
Example circles filtered
Given some partially overlapping circles on the plane, compute and show the total area covered by them, with four or six (or a little more) decimal dig... | #Tcl | Tcl | set circles {
1.6417233788 1.6121789534 0.0848270516
-1.4944608174 1.2077959613 1.1039549836
0.6110294452 -0.6907087527 0.9089162485
0.3844862411 0.2923344616 0.2375743054
-0.2495892950 -0.3832854473 1.0845181219
1.7813504266 1.6178237031 0.8162655711
-0.1985249206 -0.8343333301 0.05... | Give a code snippet in #Tcl
Total circles area
You are encouraged to solve this task according to the task description, using any language you may know.
Example circles
Example circles filtered
Given some partially overlapping circles on the plane, compute and show the total area covered by them, with four or six (... | 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... | #PL.2FI | PL/I | declare WS widechar (13) initial ('Hello world.');
put ('Character length=', length (WS));
put skip list ('Byte length=', size(WS));
declare SM graphic (13) initial ('Hello world');
put ('Character length=', length(SM));
put skip list ('Byte length=', size(trim(SM))); | Give a code snippet in #PL.2FI
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 con... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Word_frequency | Word frequency | Task
Given a text file and an integer n, print/display the n most
common words in the file (and the number of their occurrences) in decreasing frequency.
For the purposes of this task:
A word is a sequence of one or more contiguous letters.
You are free to define what a letter is.
Undersc... | #ALGOL_68 | ALGOL 68 | # find the n most common words in a file #
# use the associative array in the Associate array/iteration task #
# but with integer values #
PR read "aArrayBase.a68" PR
MODE AAKEY = STRING;
MODE AAVALUE = INT;
AAVALUE init element value = 0;
# re... | Give a code snippet in #ALGOL_68
Task
Given a text file and an integer n, print/display the n most
common words in the file (and the number of their occurrences) in decreasing frequency.
For the purposes of this task:
A word is a sequence of one or more contiguous letters.
You are free to define... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mutual_recursion | Mutual recursion | Two functions are said to be mutually recursive if the first calls the second,
and in turn the second calls the first.
Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as:
F
(
0
)
=
1
;
M
(
0
)
=
0
F
(
n
)
=
n
−
M
(
F
(
n
−
1
)
)
,
... | #REBOL | REBOL | rebol [
Title: "Mutual Recursion"
URL: http://rosettacode.org/wiki/Mutual_Recursion
References: [http://en.wikipedia.org/wiki/Hofstadter_sequence#Hofstadter_Female_and_Male_sequences]
]
f: func [
"Female."
n [integer!] "Value."
] [either 0 = n [1][n - m f n - 1]]
m: func [
"Male."
n [integer!] "Value."... | Give a code snippet in #REBOL
Two functions are said to be mutually recursive if the first calls the second,
and in turn the second calls the first.
Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as:
F
(
0
)
=
1
;
M
(
0
)
=
0
F
(
n
... | 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... | #Raku | Raku | 2e2 # same as 200e0, 2e2, 200.0e0 and 2.0e2
6.02e23
-2e48
1e-9
1e0 | Give a code snippet in #Raku
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/A... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Search_a_list | Search a list | Task[edit]
Find the index of a string (needle) in an indexable, ordered collection of strings (haystack).
Raise an exception if the needle is missing.
If there is more than one occurrence then return the smallest index to the needle.
Extra credit
Return the largest index to a needle that has multiple occurrences in ... | #Run_BASIC | Run BASIC | haystack$ = ("Zig Zag Wally Ronald Bush Krusty Charlie Bush Bozo Bush ")
needle$ = "Zag Wally Bush Chicken"
while word$(needle$,i+1," ") <> ""
i = i + 1
thisNeedle$ = word$(needle$,i," ") + " "
j = instr(haystack$,thisNeedle$)
k1 = 0
k = instr(haystack$,thisNeedle$,j+1)
while k <> 0
k1 = k
k... | Give a code snippet in #Run_BASIC
Task[edit]
Find the index of a string (needle) in an indexable, ordered collection of strings (haystack).
Raise an exception if the needle is missing.
If there is more than one occurrence then return the smallest index to the needle.
Extra credit
Return the largest index to a needl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Semiprime | Semiprime | Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers.
Semiprimes are also known as:
semi-primes
biprimes
bi-primes
2-almost primes
or simply: P2
Example
1679 = 23 × 73
(This particular number was chosen as the length of the Arecib... | #Perl | Perl | use ntheory "is_semiprime";
for ([1..100], [1675..1681], [2,4,99,100,1679,5030,32768,1234567,9876543,900660121]) {
print join(" ",grep { is_semiprime($_) } @$_),"\n";
} | Give a code snippet in #Perl
Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers.
Semiprimes are also known as:
semi-primes
biprimes
bi-primes
2-almost primes
or simply: P2
Example
1679 = 23 × 73
(This particular number was chos... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Validate_International_Securities_Identification_Number | Validate International Securities Identification Number | An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond.
Task
Write a function or program that takes a string as input, and checks whether it is a valid ISIN.
It is only valid if it has the correct format, and the embedded c... | #PicoLisp | PicoLisp | (de isin (Str)
(let Str (mapcar char (chop Str))
(and
(= 12 (length Str))
(<= 65 (car Str) 90)
(<= 65 (cadr Str) 90)
(luhn
(pack
(mapcar
'((N)
(- N (if (<= 48 N 57) 48 55)) )
Str ) ) ) ) ) )
... | Give a code snippet in #PicoLisp
An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond.
Task
Write a function or program that takes a string as input, and checks whether it is a valid ISIN.
It is only valid if it has the corr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Catalan_numbers/Pascal%27s_triangle | Catalan numbers/Pascal's triangle | Task
Print out the first 15 Catalan numbers by extracting them from Pascal's triangle.
See
Catalan Numbers and the Pascal Triangle. This method enables calculation of Catalan Numbers using only addition and subtraction.
Catalan's Triangle for a Number Triangle that generates Catalan Numbers using onl... | #Visual_Basic | Visual Basic |
Sub catalan()
Const n = 15
Dim t(n + 2) As Long
Dim i As Integer, j As Integer
t(1) = 1
For i = 1 To n
For j = i + 1 To 2 Step -1
t(j) = t(j) + t(j - 1)
Next j
t(i + 1) = t(i)
For j = i + 2 To 2 Step -1
t(j) = t(j) + t(j - 1)
Next j
... | Give a code snippet in #Visual_Basic
Task
Print out the first 15 Catalan numbers by extracting them from Pascal's triangle.
See
Catalan Numbers and the Pascal Triangle. This method enables calculation of Catalan Numbers using only addition and subtraction.
Catalan's Triangle for a Number Triangle th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Quicksort | Sorting algorithms/Quicksort |
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
... | #EasyLang | EasyLang | data[] = [ 29 4 72 44 55 26 27 77 92 5 ]
#
func qsort left right . .
while left < right
swap data[(left + right) / 2] data[left]
mid = left
for i = left + 1 to right
if data[i] < data[left]
mid += 1
swap data[i] data[mid]
.
.
swap data[left] data[mid]
call qsort le... | Give a code snippet in #EasyLang
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/Benford%27s_law | Benford's law |
This page uses content from Wikipedia. The original article was at Benford's_law. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Benford's law, also called the first-digit law, refers to the freque... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols nobinary
runSample(arg)
return
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method brenfordDeveation(nlist = Rexx[]) public static
observed = 0
loop n_ over nlist
d1 = n_.left(1)
if d1 = 0 then iterat... | Give a code snippet in #NetRexx
This page uses content from Wikipedia. The original article was at Benford's_law. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Benford's law, also called the firs... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_block_comments | Strip block comments | A block comment begins with a beginning delimiter and ends with a ending delimiter, including the delimiters. These delimiters are often multi-character sequences.
Task
Strip block comments from program text (of a programming language much like classic C).
Your demos should at least handle simple, non-ne... | #ALGOL_W | ALGOL W | begin
% strips block comments from a source %
% the source is read from standard input and the result written to %
% standard output, The comment start text is in cStart and the ending %
% is in cEnd. ... | Give a code snippet in #ALGOL_W
A block comment begins with a beginning delimiter and ends with a ending delimiter, including the delimiters. These delimiters are often multi-character sequences.
Task
Strip block comments from program text (of a programming language much like classic C).
Your demos shou... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Append_a_record_to_the_end_of_a_text_file | Append a record to the end of a text file | Many systems offer the ability to open a file for writing, such that any data written will be appended to the end of the file. Further, the file operations will always adjust the position pointer to guarantee the end of the file, even in a multitasking environment.
This feature is most useful in the case of log files,... | #C | C | #include <stdio.h>
#include <string.h>
/* note that UID & GID are of type "int" */
typedef const char *STRING;
typedef struct{STRING fullname, office, extension, homephone, email; } gecos_t;
typedef struct{STRING account, password; int uid, gid; gecos_t gecos; STRING directory, shell; } passwd_t;
#define GECOS_FMT "%... | Give a code snippet in #C
Many systems offer the ability to open a file for writing, such that any data written will be appended to the end of the file. Further, the file operations will always adjust the position pointer to guarantee the end of the file, even in a multitasking environment.
This feature is most usefu... | 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... | #Arturo | Arturo | compose: function [f,g] ->
return function [x].import:[f,g][
call f @[call g @[x]]
]
splitupper: compose 'split 'upper
print call 'splitupper ["done"] | Give a code snippet in #Arturo
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 ... | 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.... | #Ring | Ring |
# Project: Attractive Numbers
decomp = []
nump = 0
see "Attractive Numbers up to 120:" + nl
while nump < 120
decomp = []
nump = nump + 1
for i = 1 to nump
if isPrime(i) and nump%i = 0
add(decomp,i)
dec = nump/i
while dec%i = 0
add(decomp,i)
dec = dec/i
end
... | Give a code snippet in #Ring
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
Sh... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Draw_a_clock | Draw a clock | Task
Draw a clock.
More specific:
Draw a time keeping device. It can be a stopwatch, hourglass, sundial, a mouth counting "one thousand and one", anything. Only showing the seconds is required, e.g.: a watch with just a second hand will suffice. However, it must clearly change every second, and the change must cy... | #Yabasic | Yabasic | clear screen
open window 300,100
backcolor 0, 0, 0
window origin "cc"
// Display digital clock
sub digital_clock()
local t$(1), void
static as$
void = token(time$, t$(), "-")
if t$(3) <> as$ then
draw_clock(t$(1), t$(2), t$(3))
as$ = t$(3)
end if
end sub
sub draw_clock(hour$,... | Give a code snippet in #Yabasic
Task
Draw a clock.
More specific:
Draw a time keeping device. It can be a stopwatch, hourglass, sundial, a mouth counting "one thousand and one", anything. Only showing the seconds is required, e.g.: a watch with just a second hand will suffice. However, it must clearly change eve... | 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.
| #Wren | Wren | /* keyboard_macros.wren */
var GrabModeAsync = 1
var Mod1Mask = 1 << 3
var KeyPress = 2
var XK_F6 = 0xffc3
var XK_F7 = 0xffc4
foreign class XEvent {
construct new() {}
foreign eventType
}
foreign class XDisplay {
construct openDisplay(displayName) {}
foreign defaultRootWindow()
... | Give a code snippet in #Wren
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/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... | #REBOL | REBOL | rebol []
horner: func [coeffs x] [
result: 0
foreach i reverse coeffs [
result: (result * x) + i
]
return result
]
print horner [-19 7 -4 6] 3 | Give a code snippet in #REBOL
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
)
{\... | christopher/rosetta-code | |
http://rosettacode.org/wiki/McNuggets_problem | McNuggets problem | Wikipedia
The McNuggets version of the coin problem was introduced by Henri Picciotto,
who included it in his algebra textbook co-authored with Anita Wah. Picciotto
thought of the application in the 1980s while dining with his son at
McDonald's, working the problem out on a napkin. A McNugget number is
the total number... | #BCPL | BCPL | get "libhdr"
manifest $( limit = 100 $)
let start() be
$( let flags = vec limit
for i = 0 to limit do flags!i := false
for a = 0 to limit by 6
for b = a to limit by 9
for c = b to limit by 20
do flags!c := true
for i = limit to 0 by -1
unless flags!i
... | Give a code snippet in #BCPL
Wikipedia
The McNuggets version of the coin problem was introduced by Henri Picciotto,
who included it in his algebra textbook co-authored with Anita Wah. Picciotto
thought of the application in the 1980s while dining with his son at
McDonald's, working the problem out on a napkin. A McNug... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pentagram | Pentagram |
A pentagram is a star polygon, consisting of a central pentagon of which each side forms the base of an isosceles triangle. The vertex of each triangle, a point of the star, is 36 degrees.
Task
Draw (or print) a regular pentagram, in any orientation. Use a different color (or token) for stroke and fill, and backg... | #AutoHotkey | AutoHotkey |
#Include Gdip.ahk ; https://autohotkey.com/boards/viewtopic.php?f=6&t=6517
Width :=A_ScreenWidth, Height := A_ScreenHeight
Gui, 1: +E0x20 +Caption +E0x80000 +LastFound +AlwaysOnTop +ToolWindow +OwnDialogs
Gui, 1: Show, NA
hwnd1 := WinExist()
OnExit, Exit
If !pToken := Gdip_Startup()
{
MsgBox, 48, gdiplus error!, G... | Give a code snippet in #AutoHotkey
A pentagram is a star polygon, consisting of a central pentagon of which each side forms the base of an isosceles triangle. The vertex of each triangle, a point of the star, is 36 degrees.
Task
Draw (or print) a regular pentagram, in any orientation. Use a different color (or t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Happy_numbers | Happy numbers | From Wikipedia, the free encyclopedia:
A happy number is defined by the following process:
Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in a cycle which does not inclu... | #TUSCRIPT | TUSCRIPT | $$ MODE TUSCRIPT
SECTION check
IF (n!=1) THEN
n = STRINGS (n,":>/:")
LOOP/CLEAR nr=n
square=nr*nr
n=APPEND (n,square)
ENDLOOP
n=SUM(n)
r_table=QUOTES (n)
BUILD R_TABLE/word/EXACT chk=r_table
IF (seq.ma.chk) THEN
status="next"
ELSE
seq=APPEND (seq,n)
ENDIF
RELEASE r_ta... | Give a code snippet in #TUSCRIPT
From Wikipedia, the free encyclopedia:
A happy number is defined by the following process:
Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endless... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Boolean_values | Boolean values | Task
Show how to represent the boolean states "true" and "false" in a language.
If other objects represent "true" or "false" in conditionals, note it.
Related tasks
Logical operations
| #Crystal | Crystal | if false
puts "false"
elsif nil
puts "nil"
elsif Pointer(Nil).new 0
puts "null pointer"
elsif true && "any other value"
puts "finally true!"
end | Give a code snippet in #Crystal
Task
Show how to represent the boolean states "true" and "false" in a language.
If other objects represent "true" or "false" in conditionals, note it.
Related tasks
Logical operations
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_in_factors | Count in factors | Task
Write a program which counts up from 1, displaying each number as the multiplication of its prime factors.
For the purpose of this task, 1 (unity) may be shown as itself.
Example
2 is prime, so it would be shown as itself.
6 is not prime; it would be shown as
2
×
3
{\di... | #Vlang | Vlang | fn main() {
println("1: 1")
for i := 2; ; i++ {
print("$i: ")
mut x := ''
for n, f := i, 2; n != 1; f++ {
for m := n % f; m == 0; m = n % f {
print('$x$f')
x = "×"
n /= f
}
}
println('')
}
} | Give a code snippet in #Vlang
Task
Write a program which counts up from 1, displaying each number as the multiplication of its prime factors.
For the purpose of this task, 1 (unity) may be shown as itself.
Example
2 is prime, so it would be shown as itself.
6 is not prime; it would... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Wieferich_primes | Wieferich primes |
This page uses content from Wikipedia. The original article was at Wieferich prime. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In number theory, a Wieferich prime is a prime number p such th... | #FreeBASIC | FreeBASIC |
#include "isprime.bas"
function iswief( byval p as uinteger ) as boolean
if not isprime(p) then return 0
dim as integer q = 1, p2 = p^2
while p>1
q=(2*q) mod p2
p = p - 1
wend
if q=1 then return 1 else return 0
end function
for i as uinteger = 1 to 5000
if iswief(i) then pr... | Give a code snippet in #FreeBASIC
This page uses content from Wikipedia. The original article was at Wieferich prime. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In number theory, a Wieferich ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Combinations_and_permutations | Combinations and permutations |
This page uses content from Wikipedia. The original article was at Combination. 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)
This page uses content from Wikipedia. The original article was at P... | #Perl | Perl | use strict;
use warnings;
showoff( "Permutations", \&P, "P", 1 .. 12 );
showoff( "Combinations", \&C, "C", map $_*10, 1..6 );
showoff( "Permutations", \&P_big, "P", 5, 50, 500, 1000, 5000, 15000 );
showoff( "Combinations", \&C_big, "C", map $_*100, 1..10 );
sub showoff {
my ($text, $code, $fname, @n) = @_;
print ... | Give a code snippet in #Perl
This page uses content from Wikipedia. The original article was at Combination. 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)
This page uses content from Wikipedia.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Run-length_encoding | Run-length encoding | Run-length encoding
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression... | #8086_Assembly | 8086 Assembly | .model small ; 128k .exe file
.stack 1024 ; load SP with 0400h
.data ; no data segment needed
.code
start:
mov ax,@code
mov ds,ax
mov es,ax
mov si,offset TestString
mov di,offset OutputRam
cld
compressRLE:
lodsb
cmp al,0 ;null te... | Give a code snippet in #8086_Assembly
Run-length encoding
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provid... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Digital_root/Multiplicative_digital_root | Digital root/Multiplicative digital root | The multiplicative digital root (MDR) and multiplicative persistence (MP) of a number,
n
{\displaystyle n}
, is calculated rather like the Digital root except digits are multiplied instead of being added:
Set
m
{\displaystyle m}
to
n
{\displaystyle n}
and
i
{\displaystyle i}
to
0
... | #Julia | Julia |
function digitalmultroot{S<:Integer,T<:Integer}(n::S, bs::T=10)
-1 < n && 1 < bs || throw(DomainError())
ds = n
pers = 0
while bs <= ds
ds = prod(digits(ds, bs))
pers += 1
end
return (pers, ds)
end
| Give a code snippet in #Julia
The multiplicative digital root (MDR) and multiplicative persistence (MP) of a number,
n
{\displaystyle n}
, is calculated rather like the Digital root except digits are multiplied instead of being added:
Set
m
{\displaystyle m}
to
n
{\displaystyle n}
and
i
... | 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
| #Oforth | Oforth | 16 "sqrt" asMethod perform | Give a code snippet in #Oforth
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/Pi | Pi |
Create a program to continually calculate and output the next decimal digit of
π
{\displaystyle \pi }
(pi).
The program should continue forever (until it is aborted by the user) calculating and outputting each decimal digit in succession.
The output should be a decimal sequence beginning 3.14159265 ...... | #D | D | import std.stdio, std.conv, std.string;
struct PiDigits {
immutable uint nDigits;
int opApply(int delegate(ref string /*chunk of pi digit*/) dg){
// Maximum width for correct output, for type ulong.
enum size_t width = 9;
enum ulong scale = 10UL ^^ width;
enum ulong initDig... | Give a code snippet in #D
Create a program to continually calculate and output the next decimal digit of
π
{\displaystyle \pi }
(pi).
The program should continue forever (until it is aborted by the user) calculating and outputting each decimal digit in succession.
The output should be a decimal sequence... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Move-to-front_algorithm | Move-to-front algorithm | Given a symbol table of a zero-indexed array of all possible input symbols
this algorithm reversibly transforms a sequence
of input symbols into an array of output numbers (indices).
The transform in many cases acts to give frequently repeated input symbols
lower indices which is useful in some compression algorithms... | #C.23 | C# |
using System;
using System.Collections.Generic;
using System.Text;
namespace MoveToFront
{
class Program
{
private static char[] symbolTable;
private static void setSymbolTable()
{
symbolTable = "abcdefghijklmnopqrstuvwxyz".ToCharArray();
}
private stati... | Give a code snippet in #C.23
Given a symbol table of a zero-indexed array of all possible input symbols
this algorithm reversibly transforms a sequence
of input symbols into an array of output numbers (indices).
The transform in many cases acts to give frequently repeated input symbols
lower indices which is useful ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Bead_sort | Sorting algorithms/Bead 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
... | #PowerShell | PowerShell | Function BeadSort ( [Int64[]] $indata )
{
if( $indata.length -gt 1 )
{
$min = $indata[ 0 ]
$max = $indata[ 0 ]
for( $i = 1; $i -lt $indata.length; $i++ )
{
if( $indata[ $i ] -lt $min )
{
$min = $indata[ $i ]
}
if( $indata[ $i ] -gt $max ) {
$max = $indata[ $i ]
}
} #Find the min & max... | Give a code snippet in #PowerShell
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Qui... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Generate_lower_case_ASCII_alphabet | Generate lower case ASCII alphabet | Task
Generate an array, list, lazy sequence, or even an indexable string of all the lower case ASCII characters, from a to z. If the standard library contains such a sequence, show how to access it, but don't fail to show how to generate a similar sequence.
For this basic task use a reliable style of coding, a sty... | #Elixir | Elixir | iex(1)> Enum.to_list(?a .. ?z)
'abcdefghijklmnopqrstuvwxyz'
iex(2)> Enum.to_list(?a .. ?z) |> List.to_string
"abcdefghijklmnopqrstuvwxyz" | Give a code snippet in #Elixir
Task
Generate an array, list, lazy sequence, or even an indexable string of all the lower case ASCII characters, from a to z. If the standard library contains such a sequence, show how to access it, but don't fail to show how to generate a similar sequence.
For this basic task use a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Filter | Filter | Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| #Z80_Assembly | Z80 Assembly | TestArray_Metadata:
byte 4,4 ;4 rows, 4 columns.
TestArray:
byte 0,1,2,3
byte 4,5,6,7
byte 8,9,10,11
byte 12,13,14,15
OutputArray_Metadata:
byte 2,4
OutputArray:
ds 8,0 ;16 bytes each equaling zero
FilterEvenValues:
ld hl,TestArray_Metadata
ld a,(hl)
inc hl
ld b,(hl)
inc hl ;LD HL,TestA... | Give a code snippet in #Z80_Assembly
Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| 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... | #Forth | Forth | \ Gforth 0.7.9_20211014
: fusc ( n -- n) \ input n -- output fusc(n)
dup dup 0= swap 1 = or \ n = 0 or 1
if exit \ return n
else dup 2 mod 0= \ test even
if 2/ recurse \ even fusc(n)= fusc(n/2)
else du... | Give a code snippet in #Forth
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 st... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Host_introspection | Host introspection | Print the word size and endianness of the host machine.
See also: Variable size/Get
| #Action.21 | Action! | PROC Main()
PrintE("All Atari 8-bit computers use little-endian word of 16-bits size.")
RETURN | Give a code snippet in #Action.21
Print the word size and endianness of the host machine.
See also: Variable size/Get
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Happy_numbers | Happy numbers | From Wikipedia, the free encyclopedia:
A happy number is defined by the following process:
Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in a cycle which does not inclu... | #Phix | Phix | function is_happy(integer n)
sequence seen = {}
while n>1 do
seen &= n
integer k = 0
while n>0 do
k += power(remainder(n,10),2)
n = floor(n/10)
end while
n = k
if find(n,seen) then
return false
end if
end while
r... | Give a code snippet in #Phix
From Wikipedia, the free encyclopedia:
A happy number is defined by the following process:
Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stair-climbing_puzzle | Stair-climbing puzzle | From Chung-Chieh Shan (LtU):
Your stair-climbing robot has a very simple low-level API: the "step" function takes no argument and attempts to climb one step as a side effect. Unfortunately, sometimes the attempt fails and the robot clumsily falls one step instead. The "step" function detects what happens and returns a... | #SAS | SAS |
%macro step();
%sysfunc(round(%sysfunc(ranuni(0))))
%mend step;
| Give a code snippet in #SAS
From Chung-Chieh Shan (LtU):
Your stair-climbing robot has a very simple low-level API: the "step" function takes no argument and attempts to climb one step as a side effect. Unfortunately, sometimes the attempt fails and the robot clumsily falls one step instead. The "step" function detec... | christopher/rosetta-code |
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