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/Video_display_modes | Video display modes | The task is to demonstrate how to switch video display modes within the language. A brief description of the supported video modes would be useful.
| #AmigaBASIC | AmigaBASIC | SCREEN 1,320,200,5,1 | Give a code snippet in #AmigaBASIC
The task is to demonstrate how to switch video display modes within the language. A brief description of the supported video modes would be useful.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Display_a_linear_combination | Display a linear combination | Task
Display a finite linear combination in an infinite vector basis
(
e
1
,
e
2
,
…
)
{\displaystyle (e_{1},e_{2},\ldots )}
.
Write a function that, when given a finite list of scalars
(
α
1
,
α
2
,
…
)
{\displaystyle (\alpha ^{1},\alpha ^{2},\ldots )}
,
creates a string representing t... | #jq | jq | def linearCombo:
reduce to_entries[] as {key: $k,value: $v} ("";
if $v == 0 then .
else
(if $v < 0 and length==0 then "-"
elif $v < 0 then " - "
elif $v > 0 and length==0 then ""
else " + "
end) as $sign
| ($v|fabs... | Give a code snippet in #jq
Task
Display a finite linear combination in an infinite vector basis
(
e
1
,
e
2
,
…
)
{\displaystyle (e_{1},e_{2},\ldots )}
.
Write a function that, when given a finite list of scalars
(
α
1
,
α
2
,
…
)
{\displaystyle (\alpha ^{1},\alpha ^{2},\ldots )}
,
cre... | 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.
| #Objeck | Objeck |
use Structure;
bundle Default {
class Evens {
function : Main(args : String[]) ~ Nil {
values := IntVector->New([1, 2, 3, 4, 5]);
f := Filter(Int) ~ Bool;
evens := values->Filter(f);
each(i : evens) {
evens->Get(i)->PrintLine();
};
}
function : Filter(v : Int)... | Give a code snippet in #Objeck
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/Fork | Fork | Task
Spawn a new process which can run simultaneously with, and independently of, the original parent process.
| #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols binary
runSample(arg)
return
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method runSample(arg) private static
do
pb = ProcessBuilder([String ''])
env = pb.environment()
currentuser = String env.g... | Give a code snippet in #NetRexx
Task
Spawn a new process which can run simultaneously with, and independently of, the original parent process.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Pointers_and_references | Pointers and references |
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 |... | #PureBasic | PureBasic | Define varA.i = 5, varB.i = 0, *myInteger.Integer
*myInteger = @varA ;set pointer to address of an integer variable
varB = *myInteger\i + 3 ;set variable to the 3 + value of dereferenced pointer, i.e varB = 8 | Give a code snippet in #PureBasic
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operati... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Compare_a_list_of_strings | Compare a list of strings | Task
Given a list of arbitrarily many strings, show how to:
test if they are all lexically equal
test if every string is lexically less than the one after it (i.e. whether the list is in strict ascending order)
Each of those two tests should result in a single true or false value, which could be used as t... | #Lua | Lua | function identical(t_str)
_, fst = next(t_str)
if fst then
for _, i in pairs(t_str) do
if i ~= fst then return false end
end
end
return true
end
function ascending(t_str)
prev = false
for _, i in ipairs(t_str) do
if prev and prev >= i then return false end
... | Give a code snippet in #Lua
Task
Given a list of arbitrarily many strings, show how to:
test if they are all lexically equal
test if every string is lexically less than the one after it (i.e. whether the list is in strict ascending order)
Each of those two tests should result in a single true or false va... | christopher/rosetta-code | |
http://rosettacode.org/wiki/AKS_test_for_primes | AKS test for primes | The AKS algorithm for testing whether a number is prime is a polynomial-time algorithm based on an elementary theorem about Pascal triangles.
The theorem on which the test is based can be stated as follows:
a number
p
{\displaystyle p}
is prime if and only if all the coefficients of the polynomial ... | #Phix | Phix | -- demo/rosetta/AKSprimes.exw
-- Does not work for primes above 53, which is actually beyond the original task anyway.
-- Translated from the C version, just about everything is (working) out-by-1, what fun.
sequence c = repeat(0,100)
procedure coef(integer n)
-- out-by-1, ie coef(1)==^0, coef(2)==^1, coef(3)==^2 e... | Give a code snippet in #Phix
The AKS algorithm for testing whether a number is prime is a polynomial-time algorithm based on an elementary theorem about Pascal triangles.
The theorem on which the test is based can be stated as follows:
a number
p
{\displaystyle p}
is prime if and only if all the c... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Newline_omission | Hello world/Newline omission | Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output.
Task
Display the string Goodbye, World! without a trailing newline.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Standard error
Hello world/Text
| #Agena | Agena | io.write( "Goodbye, World!" ) | Give a code snippet in #Agena
Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output.
Task
Display the string Goodbye, World! without a trailing newline.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Stand... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Playing_cards | Playing cards | Task
Create a data structure and the associated methods to define and manipulate a deck of playing cards.
The deck should contain 52 unique cards.
The methods must include the ability to:
make a new deck
shuffle (randomize) the deck
deal from the deck
print the current contents of a deck
Each card mu... | #BBC_BASIC | BBC BASIC | DIM Deck{ncards%, card&(51)}, Suit$(3), Rank$(12)
Suit$() = "Clubs", "Diamonds", "Hearts", "Spades"
Rank$() = "Ace", "Two", "Three", "Four", "Five", "Six", "Seven", \
\ "Eight", "Nine", "Ten", "Jack", "Queen", "King"
PRINT "Creating a new deck..."
PROCnewdeck(deck1{})
... | Give a code snippet in #BBC_BASIC
Task
Create a data structure and the associated methods to define and manipulate a deck of playing cards.
The deck should contain 52 unique cards.
The methods must include the ability to:
make a new deck
shuffle (randomize) the deck
deal from the deck
print the curre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Deconvolution/1D | Deconvolution/1D | The convolution of two functions
F
{\displaystyle {\mathit {F}}}
and
H
{\displaystyle {\mathit {H}}}
of
an integer variable is defined as the function
G
{\displaystyle {\mathit {G}}}
satisfying
G
(
n
)
=
∑
m
=
−
∞
∞
F
(
m
)
H
(
n
−
m
)
{\displaystyle G(n)=\sum _{m=-\inft... | #Java | Java | import java.util.Arrays;
public class Deconvolution1D {
public static int[] deconv(int[] g, int[] f) {
int[] h = new int[g.length - f.length + 1];
for (int n = 0; n < h.length; n++) {
h[n] = g[n];
int lower = Math.max(n - f.length + 1, 0);
for (int i = lower; i ... | Give a code snippet in #Java
The convolution of two functions
F
{\displaystyle {\mathit {F}}}
and
H
{\displaystyle {\mathit {H}}}
of
an integer variable is defined as the function
G
{\displaystyle {\mathit {G}}}
satisfying
G
(
n
)
=
∑
m
=
−
∞
∞
F
(
m
)
H
(
n
−
m
)
{\dis... | christopher/rosetta-code | |
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
| #AArch64_Assembly | AArch64 Assembly |
/* ARM assembly AARCH64 Raspberry PI 3B */
/* program inputWin64.s */
/*******************************************/
/* Constantes file */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly*/
.include "../includeConstantesARM... | Give a code snippet in #AArch64_Assembly
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/Levenshtein_distance | Levenshtein distance |
This page uses content from Wikipedia. The original article was at Levenshtein distance. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In information theory and computer science, the Levenshtein ... | #COBOL | COBOL |
identification division.
program-id. Levenshtein.
environment division.
configuration section.
repository.
function all intrinsic.
data division.
working-storage section.
77 string-a pic x(255).
77 string-b pic... | Give a code snippet in #COBOL
This page uses content from Wikipedia. The original article was at Levenshtein distance. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In information theory and com... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Trabb_Pardo%E2%80%93Knuth_algorithm | Trabb Pardo–Knuth algorithm | The TPK algorithm is an early example of a programming chrestomathy.
It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages.
The report traces the early history of work in developing computer languages in the 1940s and 1950s, giving several translations of... | #Julia | Julia | f(x) = √abs(x) + 5x^3
for i in reverse(split(readline()))
v = f(parse(Int, i))
println("$(i): ", v > 400 ? "TOO LARGE" : v)
end | Give a code snippet in #Julia
The TPK algorithm is an early example of a programming chrestomathy.
It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages.
The report traces the early history of work in developing computer languages in the 1940s and 1950s,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number/With_feedback_(player) | Guess the number/With feedback (player) | Task
Write a player for the game that follows the following rules:
The scorer will choose a number between set limits. The computer player will print a guess of the target number. The computer asks for a score of whether its guess is higher than, lower than, or equal to the target. The computer guesses, and the score... | #Action.21 | Action! | PROC Main()
BYTE n,min=[1],max=[100]
CHAR c
PrintF("Think a number in range %B-%B%E",min,max)
DO
n=(max+min) RSH 1
PrintF("My guess is %B%E",n)
PrintF("Is it (E)qual, (L)ower or (H)igher?")
c=GetD(7)
Put(c) PutE()
IF c='E THEN
Print("I guessed!")
EXIT
ELSEIF c='L THEN
... | Give a code snippet in #Action.21
Task
Write a player for the game that follows the following rules:
The scorer will choose a number between set limits. The computer player will print a guess of the target number. The computer asks for a score of whether its guess is higher than, lower than, or equal to the target. ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Look-and-say_sequence | Look-and-say sequence | The Look and say sequence is a recursively defined sequence of numbers studied most notably by John Conway.
The look-and-say sequence is also known as the Morris Number Sequence, after cryptographer Robert Morris, and the puzzle What is the next number in the sequence 1, 11, 21, 1211, 11122... | #Pascal | Pascal | program LookAndSayDemo(input, output);
{$IFDEF FPC}
{$MODE DELPHI}
{$ENDIF}
uses
SysUtils;
function LookAndSay(s: string): string;
var
item: char;
index: integer;
count: integer;
begin
Result := '';
item := s[1];
count := 1;
for index := 2 to length(s) do
if item = s[index] then
inc(co... | Give a code snippet in #Pascal
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/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 ... | #Swift | Swift | func perfectShuffle<T>(_ arr: [T]) -> [T]? {
guard arr.count & 1 == 0 else {
return nil
}
let half = arr.count / 2
var res = [T]()
for i in 0..<half {
res.append(arr[i])
res.append(arr[i + half])
}
return res
}
let decks = [
Array(1...8),
Array(1...24),
Array(1...52),
Array(1..... | Give a code snippet in #Swift
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cramer%27s_rule | Cramer's rule | linear algebra
Cramer's rule
system of linear equations
Given
{
a
1
x
+
b
1
y
+
c
1
z
=
d
1
a
2
x
+
b
2
y
+
c
2
z
=
d
2
a
3
x
+
b
3
y
+
c
3
z
=
d
3
{\displaystyle \left\{{\begin{matrix}a_{1}x+b_{1}y+c_{1}z&={\color {red}d_{1... | #11l | 11l | F det(mm)
V m = copy(mm)
V result = 1.0
L(j) 0 .< m.len
V imax = j
L(i) j + 1 .< m.len
I m[i][j] > m[imax][j]
imax = i
I imax != j
swap(&m[imax], &m[j])
result = -result
I abs(m[j][j]) < 1e-12
R Float.infinity
L(i) j + 1 .< m... | Give a code snippet in #11l
linear algebra
Cramer's rule
system of linear equations
Given
{
a
1
x
+
b
1
y
+
c
1
z
=
d
1
a
2
x
+
b
2
y
+
c
2
z
=
d
2
a
3
x
+
b
3
y
+
c
3
z
=
d
3
{\displaystyle \left\{{\begin{matrix}a_{1}x+b_{... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pick_random_element | Pick random element | Demonstrate how to pick a random element from a list.
| #PicoLisp | PicoLisp | (get Lst (rand 1 (length Lst))) | Give a code snippet in #PicoLisp
Demonstrate how to pick a random element from a list.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Regular_expressions | Regular expressions |
Task
match a string against a regular expression
substitute part of a string using a regular expression
| #GeneXus | GeneXus | &string = &string.ReplaceRegEx("^\s+|\s+$", "") // it's a trim!
&string = &string.ReplaceRegEx("Another (Match)", "Replacing $1") // Using replace groups | Give a code snippet in #GeneXus
Task
match a string against a regular expression
substitute part of a string using a regular expression
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number | Guess the number | Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a "Well guessed!" message, a... | #MiniScript | MiniScript | num = ceil(rnd*10)
while true
x = val(input("Your guess?"))
if x == num then
print "Well guessed!"
break
end if
end while | Give a code snippet in #MiniScript
Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pythagorean_quadruples | Pythagorean quadruples |
One form of Pythagorean quadruples is (for positive integers a, b, c, and d):
a2 + b2 + c2 = d2
An example:
22 + 32 + 62 = 72
which is:
4 + 9 + 36 = 49
Task
For positive integers up 2,200 (inclusive), for all values of ... | #Crystal | Crystal | n = 2200
l_add, l = Hash(Int32, Bool).new(false), Hash(Int32, Bool).new(false)
(1..n).each do |x|
x2 = x * x
(x..n).each { |y| l_add[x2 + y * y] = true }
end
s = 3
(1..n).each do |x|
s1 = s
s += 2
s2 = s
((x+1)..n).each do |y|
l[y] = true if l_add[s1]
s1 += s2
s2 += 2
end
end
puts (1..n)... | Give a code snippet in #Crystal
One form of Pythagorean quadruples is (for positive integers a, b, c, and d):
a2 + b2 + c2 = d2
An example:
22 + 32 + 62 = 72
which is:
4 + 9 + 36 = 49
Task
For positive integers up 2,200 (i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Cocktail_sort_with_shifting_bounds | Sorting algorithms/Cocktail sort with shifting bounds |
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
... | #Python | Python |
"""
Python example of
http://rosettacode.org/wiki/Sorting_algorithms/Cocktail_sort_with_shifting_bounds
based on
http://rosettacode.org/wiki/Sorting_algorithms/Cocktail_sort#Python
"""
def cocktailshiftingbounds(A):
beginIdx = 0
endIdx = len(A) - 1
while beginIdx <= endIdx:
newBegin... | Give a code snippet in #Python
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 s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nth_root | Nth root | Task
Implement the algorithm to compute the principal nth root
A
n
{\displaystyle {\sqrt[{n}]{A}}}
of a positive real number A, as explained at the Wikipedia page.
| #PureBasic | PureBasic | #Def_p=0.001
Procedure.d Nth_root(n.i, A.d, p.d=#Def_p)
Protected Dim x.d(1)
x(0)=A: x(1)=A/n
While Abs(x(1)-x(0))>p
x(0)=x(1)
x(1)=((n-1.0)*x(1)+A/Pow(x(1),n-1.0))/n
Wend
ProcedureReturn x(1)
EndProcedure
;//////////////////////////////
Debug "125'th root of 5642 is"
Debug Pow(5642,1/125)
Debug ... | Give a code snippet in #PureBasic
Task
Implement the algorithm to compute the principal nth root
A
n
{\displaystyle {\sqrt[{n}]{A}}}
of a positive real number A, as explained at the Wikipedia page.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Pascal%27s_triangle | Pascal's triangle | Pascal's triangle is an arithmetic and geometric figure often associated with the name of Blaise Pascal, but also studied centuries earlier in India, Persia, China and elsewhere.
Its first few rows look like this:
1
1 1
1 2 1
1 3 3 1
where each element of each row is either 1 or the sum of the two elemen... | #Delphi | Delphi | program PascalsTriangle;
procedure Pascal(r:Integer);
var
i, c, k:Integer;
begin
for i := 0 to r - 1 do
begin
c := 1;
for k := 0 to i do
begin
Write(c:3);
c := c * (i - k) div (k + 1);
end;
Writeln;
end;
end;
begin
Pascal(9);
end. | Give a code snippet in #Delphi
Pascal's triangle is an arithmetic and geometric figure often associated with the name of Blaise Pascal, but also studied centuries earlier in India, Persia, China and elsewhere.
Its first few rows look like this:
1
1 1
1 2 1
1 3 3 1
where each element of each row is eithe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_size | File size | Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| #HicEst | HicEst | READ(FILE="input.txt", LENgth=bytes) ! bytes = -1 if not existent
READ(FILE="C:\input.txt", LENgth=bytes) ! bytes = -1 if not existent | Give a code snippet in #HicEst
Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Least_common_multiple | Least common multiple | Least common multiple
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Compute the least common multiple (LCM) of two integers.
Given m and n, the least common multiple is the smallest positive integer that has both m and n as factor... | #Fortran | Fortran |
integer function lcm(a,b)
integer:: a,b
lcm = a*b / gcd(a,b)
end function lcm
integer function gcd(a,b)
integer :: a,b,t
do while (b/=0)
t = b
b = mod(a,b)
a = t
end do
gcd = abs(a)
end function gcd
| Give a code snippet in #Fortran
Least common multiple
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Compute the least common multiple (LCM) of two integers.
Given m and n, the least common multiple is the smallest positive integer that h... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knight%27s_tour | Knight's tour |
Task
Problem: you have a standard 8x8 chessboard, empty but for a single knight on some square. Your task is to emit a series of legal knight moves that result in the knight visiting every square on the chessboard exactly once. Note that it is not a requirement that the tour be "closed"; that is, the knight need not e... | #D | D | import std.stdio, std.algorithm, std.random, std.range,
std.conv, std.typecons, std.typetuple;
int[N][N] knightTour(size_t N=8)(in string start)
in {
assert(start.length >= 2);
} body {
static struct P { int x, y; }
immutable P[8] moves = [P(2,1), P(1,2), P(-1,2), P(-2,1),
... | Give a code snippet in #D
Task
Problem: you have a standard 8x8 chessboard, empty but for a single knight on some square. Your task is to emit a series of legal knight moves that result in the knight visiting every square on the chessboard exactly once. Note that it is not a requirement that the tour be "closed"; tha... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Primes_-_allocate_descendants_to_their_ancestors | Primes - allocate descendants to their ancestors | The concept, is to add the decomposition into prime factors of a number to get its 'ancestors'.
The objective is to demonstrate that the choice of the algorithm can be crucial in term of performance.
This solution could be compared to the solution that would use the decomposition into primes for all the numbers betw... | #Haskell | Haskell | {-# LANGUAGE DeriveFunctor #-}
import Data.Numbers.Primes (isPrime)
import Data.List
------------------------------------------------------------
-- memoization utilities
type Memo2 a = Memo (Memo a)
data Memo a = Node a (Memo a) (Memo a)
deriving Functor
memo :: Integral a => Memo p -> a -> p
memo (Node a l ... | Give a code snippet in #Haskell
The concept, is to add the decomposition into prime factors of a number to get its 'ancestors'.
The objective is to demonstrate that the choice of the algorithm can be crucial in term of performance.
This solution could be compared to the solution that would use the decomposition int... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Amb | Amb | Define and give an example of the Amb operator.
The Amb operator (short for "ambiguous") expresses nondeterminism. This doesn't refer to randomness (as in "nondeterministic universe") but is closely related to the term as it is used in automata theory ("non-deterministic finite automaton").
The Amb operator takes a v... | #Bracmat | Bracmat | ( ( Amb
= first last list words word solution
. !arg:(?first.?list)
& ( !list:
| !list:(.?words) ?list
& !words
: ?
%( @(?word:!first ? @?last)
& Amb$(!last.!list):?solution
& !word !solution:?solution
... | Give a code snippet in #Bracmat
Define and give an example of the Amb operator.
The Amb operator (short for "ambiguous") expresses nondeterminism. This doesn't refer to randomness (as in "nondeterministic universe") but is closely related to the term as it is used in automata theory ("non-deterministic finite automat... | 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... | #C.2B.2B | C++ | void number_reversal_game()
{
cout << "Number Reversal Game. Type a number to flip the first n numbers.";
cout << "You win by sorting the numbers in ascending order.";
cout << "Anything besides numbers are ignored.\n";
cout << "\t |1__2__3__4__5__6__7__8__9|\n";
int list[9] = {1,2,3,4,5,6,7,8,9};
do
... | Give a code snippet in #C.2B.2B
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Probabilistic_choice | Probabilistic choice | Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because floating point arithmetic is invol... | #Sidef | Sidef | define TRIALS = 1e4;
func prob_choice_picker(options) {
var n = 0;
var a = [];
options.each { |k,v|
n += v;
a << [n, k];
}
func {
var r = 1.rand;
a.first{|e| r <= e[0] }[1];
}
}
var ps = Hash(
aleph => 1/5,
beth => 1/6,
gimel => 1/7,
daleth => ... | Give a code snippet in #Sidef
Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because flo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rock-paper-scissors | Rock-paper-scissors | Task
Implement the classic children's game Rock-paper-scissors, as well as a simple predictive AI (artificial intelligence) player.
Rock Paper Scissors is a two player game.
Each player chooses one of rock, paper or scissors, without knowing the other player's choice.
The winner is decided by a set of rules:
... | #Picat | Picat | go ?=>
println("\nEnd terms with '.'.\n'quit.' ends the session.\n"),
Prev = findall(P,beats(P,_)),
ChoiceMap = new_map([P=0 : P in Prev]),
ResultMap = new_map([computer_wins=0,user_wins=0,draw=0]),
play(Prev,ChoiceMap,ResultMap),
nl,
println("Summary:"),
println(choiceMap=ChoiceMap),
println(resultMa... | Give a code snippet in #Picat
Task
Implement the classic children's game Rock-paper-scissors, as well as a simple predictive AI (artificial intelligence) player.
Rock Paper Scissors is a two player game.
Each player chooses one of rock, paper or scissors, without knowing the other player's choice.
The winner... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rosetta_Code/Count_examples | Rosetta Code/Count examples | task
Essentially, count the number of occurrences of =={{header| on each task page.
Output:
100 doors: 20 examples.
99 Bottles of Beer: 29 examples.
Abstract type: 10 examples.
Total: X examples.
For a full output, updated periodically, see Rosetta Code/Count examples/Full list.
You'll need to use the Media Wiki AP... | #Oz | Oz | declare
[HTTPClient] = {Module.link ['x-ozlib://mesaros/net/HTTPClient.ozf']}
[XMLParser] = {Module.link ['x-oz://system/xml/Parser.ozf']}
[StringX] = {Module.link ['x-oz://system/String.ozf']}
[Regex] = {Module.link ['x-oz://contrib/regex']}
AllTasksUrl = "http://rosettacode.org/mw/api.php?action=query&lis... | Give a code snippet in #Oz
task
Essentially, count the number of occurrences of =={{header| on each task page.
Output:
100 doors: 20 examples.
99 Bottles of Beer: 29 examples.
Abstract type: 10 examples.
Total: X examples.
For a full output, updated periodically, see Rosetta Code/Count examples/Full list.
You'll n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Playfair_cipher | Playfair cipher | Playfair cipher
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Implement a Playfair cipher for encryption and decryption.
The user must be able to choose J = I or no Q in the alphabet.
The output of the encrypted and decrypted message ... | #Phix | Phix | with javascript_semantics
constant keyword = "Playfair example",
option = 'Q' -- ignore Q
-- option = 'J' -- replace J with I
sequence table,
findchar
procedure build_table()
table = repeat(repeat(' ',5),5)
findchar = repeat(0,26)
findchar[option-'A'+1] = {0,0}
-- (note any (J... | Give a code snippet in #Phix
Playfair cipher
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Implement a Playfair cipher for encryption and decryption.
The user must be able to choose J = I or no Q in the alphabet.
The output of the en... | christopher/rosetta-code | |
http://rosettacode.org/wiki/24_game | 24 game | The 24 Game tests one's mental arithmetic.
Task
Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed.
The program should prompt for the player to enter an arithmetic expression using just those, and all of those four digits, used exactly once each. T... | #Red | Red |
Red []
print "Evaluation from left to right with no precedence, unless you use parenthesis." print ""
a: "123456789"
guess: ""
valid: ""
sucess: false
random/seed now/time
loop 4 [append valid last random a]
print ["The numbers are: " valid/1 ", " valid/2 ", " valid/3 " and " valid/4]
sort valid
insert valid " "
ex... | Give a code snippet in #Red
The 24 Game tests one's mental arithmetic.
Task
Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed.
The program should prompt for the player to enter an arithmetic expression using just those, and all of those four digi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_common_directory_path | Find common directory path | Create a routine that, given a set of strings representing directory paths and a single character directory separator, will return a string representing that part of the directory tree that is common to all the directories.
Test your routine using the forward slash '/' character as the directory separator and the foll... | #Haskell | Haskell | import Data.List
-- Return the common prefix of two lists.
commonPrefix2 (x:xs) (y:ys) | x == y = x : commonPrefix2 xs ys
commonPrefix2 _ _ = []
-- Return the common prefix of zero or more lists.
commonPrefix (xs:xss) = foldr commonPrefix2 xs xss
commonPrefix _ = []
-- Split a string into path components.
splitPa... | Give a code snippet in #Haskell
Create a routine that, given a set of strings representing directory paths and a single character directory separator, will return a string representing that part of the directory tree that is common to all the directories.
Test your routine using the forward slash '/' character as the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Kaprekar_numbers | Kaprekar numbers | A positive integer is a Kaprekar number if:
It is 1 (unity)
The decimal representation of its square may be split once into two parts consisting of positive integers which sum to the original number.
Note that a split resulting in a part consisting purely of 0s is not valid,
as 0 is not considered positive.
... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | KaprekaQ[1] = True;
KaprekaQ[n_Integer] := Block[{data = IntegerDigits[n^2], last = False, i = 1},
While[i < Length[data] && FromDigits[data[[i + 1 ;;]]] =!= 0 && Not[last],
last = FromDigits[data[[;; i]]] + FromDigits[data[[i + 1 ;;]]] == n;
i++]; last];
Select[Range[10000], KaprekaQ]
Length[Select[Range[100... | Give a code snippet in #Mathematica.2FWolfram_Language
A positive integer is a Kaprekar number if:
It is 1 (unity)
The decimal representation of its square may be split once into two parts consisting of positive integers which sum to the original number.
Note that a split resulting in a part consisting pure... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Aliquot_sequence_classifications | Aliquot sequence classifications | An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications for non termination:
If the s... | #REXX | REXX | /*REXX program classifies various positive integers for types of aliquot sequences. */
parse arg low high $L /*obtain optional arguments from the CL*/
high= word(high low 10,1); low= word(low 1,1) /*obtain the LOW and HIGH (range). */
if $L='' then $L=11 12 28 496 220 1184 12496 1... | Give a code snippet in #REXX
An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:... | #OCaml | OCaml | let () =
Array.iter print_endline (
Sys.readdir Sys.argv.(1) ) | Give a code snippet in #OCaml
Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Exampl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Harmonic_series | Harmonic series |
This page uses content from Wikipedia. The original article was at Harmonic number. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In mathematics, the n-th harmonic number is the sum of the recipr... | #BASIC | BASIC | h = 0.0
print "The first twenty harmonic numbers are:"
for n = 1 to 20
h += 1.0 / n
print n, h
next n
print
h = 1 : n = 2
for i = 2 to 10
while h < i
h += 1.0 / n
n += 1
end while
print "The first harmonic number greater than "; i; " is "; h; ", at position "; n-1
next i
end | Give a code snippet in #BASIC
This page uses content from Wikipedia. The original article was at Harmonic number. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In mathematics, the n-th harmonic ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Combinations_with_repetitions | Combinations with repetitions | The set of combinations with repetitions is computed from a set,
S
{\displaystyle S}
(of cardinality
n
{\displaystyle n}
), and a size of resulting selection,
k
{\displaystyle k}
, by reporting the sets of cardinality
k
{\displaystyle k}
where each member of those sets is chosen from
S... | #Mercury | Mercury | :- module comb.
:- interface.
:- import_module list, int, bag.
:- pred choose(list(T)::in, int::in, bag(T)::out) is nondet.
:- pred choose_all(list(T)::in, int::in, list(list(T))::out) is det.
:- pred count_choices(list(T)::in, int::in, int::out) is det.
:- implementation.
:- import_module solutions.
choose(L, N,... | Give a code snippet in #Mercury
The set of combinations with repetitions is computed from a set,
S
{\displaystyle S}
(of cardinality
n
{\displaystyle n}
), and a size of resulting selection,
k
{\displaystyle k}
, by reporting the sets of cardinality
k
{\displaystyle k}
where each member o... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Towers_of_Hanoi | Towers of Hanoi | Task
Solve the Towers of Hanoi problem with recursion.
| #Fortran | Fortran | PROGRAM TOWER
CALL Move(4, 1, 2, 3)
CONTAINS
RECURSIVE SUBROUTINE Move(ndisks, from, to, via)
INTEGER, INTENT (IN) :: ndisks, from, to, via
IF (ndisks == 1) THEN
WRITE(*, "(A,I1,A,I1)") "Move disk from pole ", from, " to pole ", to
ELSE
CALL Move(ndisks-1, from, via, to)
CAL... | Give a code snippet in #Fortran
Task
Solve the Towers of Hanoi problem with recursion.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/String_case | String case | Task
Take the string alphaBETA and demonstrate how to convert it to:
upper-case and
lower-case
Use the default encoding of a string literal or plain ASCII if there is no string literal in your language.
Note: In some languages alphabets toLower and toUpper is not reversable.
Show any additional... | #ALGOL_68 | ALGOL 68 | #!/usr/local/bin/a68g --script #
# Demonstrate toupper and tolower for standard ALGOL 68
strings. This does not work for multibyte character sets. #
INT l2u = ABS "A" - ABS "a";
PROC to upper = (CHAR c)CHAR:
(ABS "a" > ABS c | c |: ABS c > ABS "z" | c | REPR ( ABS c + l2u ));
PROC to lower = (CHAR c)CHAR:
... | Give a code snippet in #ALGOL_68
Task
Take the string alphaBETA and demonstrate how to convert it to:
upper-case and
lower-case
Use the default encoding of a string literal or plain ASCII if there is no string literal in your language.
Note: In some languages alphabets toLower and toUpper is no... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dynamic_variable_names | Dynamic variable names | Task
Create a variable with a user-defined name.
The variable name should not be written in the program text, but should be taken from the user dynamically.
See also
Eval in environment is a similar task.
| #AutoHotkey | AutoHotkey | InputBox, Dynamic, Variable Name
%Dynamic% = hello
ListVars
MsgBox % %dynamic% ; says hello | Give a code snippet in #AutoHotkey
Task
Create a variable with a user-defined name.
The variable name should not be written in the program text, but should be taken from the user dynamically.
See also
Eval in environment is a similar task.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #MATLAB | MATLAB | function [varargout] = emptyprogram(varargin) | Give a code snippet in #MATLAB
Task
Create the simplest possible program that is still considered "correct."
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Mean_angle | Averages/Mean angle | When calculating the average or mean of an angle one has to take into account how angles wrap around so that any angle in degrees plus any integer multiple of 360 degrees is a measure of the same angle.
If one wanted an average direction of the wind over two readings where the first reading was of 350 degrees and the ... | #Aime | Aime | real
mean(list l)
{
integer i;
real x, y;
x = y = 0;
i = 0;
while (i < l_length(l)) {
x += Gcos(l[i]);
y += Gsin(l[i]);
i += 1;
}
return Gatan2(y / l_length(l), x / l_length(l));
}
integer
main(void)
{
o_form("mean of 1st set: /d6/\n", mean(l_effect(350, 1... | Give a code snippet in #Aime
When calculating the average or mean of an angle one has to take into account how angles wrap around so that any angle in degrees plus any integer multiple of 360 degrees is a measure of the same angle.
If one wanted an average direction of the wind over two readings where the first readi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_concatenation | Array concatenation | Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| #SETL | SETL | A := [1, 2, 3];
B := [3, 4, 5];
print(A + B); -- [1 2 3 3 4 5] | Give a code snippet in #SETL
Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Zebra_puzzle | Zebra puzzle | Zebra puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
The Zebra puzzle, a.k.a. Einstein's Riddle,
is a logic puzzle which is to be solved programmatically.
It has several variants, one of them this:
There are five houses.
The English man lives ... | #AutoHotkey | AutoHotkey | REM The names (only used for printing the results):
DIM Drink$(4), Nation$(4), Colr$(4), Smoke$(4), Animal$(4)
Drink$() = "Beer", "Coffee", "Milk", "Tea", "Water"
Nation$() = "Denmark", "England", "Germany", "Norway", "Sweden"
Colr$() = "Blue", "Green", "Red", "White", "Yellow"
Sm... | Give a code snippet in #AutoHotkey
Zebra puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
The Zebra puzzle, a.k.a. Einstein's Riddle,
is a logic puzzle which is to be solved programmatically.
It has several variants, one of them this:
There are fi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pig_the_dice_game | Pig the dice game | The game of Pig is a multiplayer game played with a single six-sided die. The
object of the game is to reach 100 points or more.
Play is taken in turns. On each person's turn that person has the option of either:
Rolling the dice: where a roll of two to six is added to their score for that turn and th... | #Erlang | Erlang |
-module( pig_dice ).
-export( [game/1, goal/0, hold/2, player_name/1, players_totals/1, quit/2, roll/2, score/1, task/0] ).
-record( player, {name, score=0, total=0} ).
game( [_Player | _T]=Players ) ->
My_pid = erlang:self(),
erlang:spawn_link( fun() -> random:seed(os:timestamp()), game_loop( [#player{... | Give a code snippet in #Erlang
The game of Pig is a multiplayer game played with a single six-sided die. The
object of the game is to reach 100 points or more.
Play is taken in turns. On each person's turn that person has the option of either:
Rolling the dice: where a roll of two to six is added to ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Magnanimous_numbers | Magnanimous numbers | A magnanimous number is an integer where there is no place in the number where a + (plus sign) could be added between any two digits to give a non-prime sum.
E.G.
6425 is a magnanimous number. 6 + 425 == 431 which is prime; 64 + 25 == 89 which is prime; 642 + 5 == 647 which is prime.
3538 is not a magnanimous numb... | #Visual_Basic_.NET | Visual Basic .NET | Imports System, System.Console
Module Module1
Dim np As Boolean()
Sub ms(ByVal lmt As Long)
np = New Boolean(CInt(lmt)) {} : np(0) = True : np(1) = True
Dim n As Integer = 2, j As Integer = 1 : While n < lmt
If Not np(n) Then
Dim k As Long = CLng(n) * n
... | Give a code snippet in #Visual_Basic_.NET
A magnanimous number is an integer where there is no place in the number where a + (plus sign) could be added between any two digits to give a non-prime sum.
E.G.
6425 is a magnanimous number. 6 + 425 == 431 which is prime; 64 + 25 == 89 which is prime; 642 + 5 == 647 whic... | 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... | #Groovy | Groovy | import static Man.*
import static Woman.*
Map<Woman,Man> match(Map<Man,Map<Woman,Integer>> guysGalRanking, Map<Woman,Map<Man,Integer>> galsGuyRanking) {
Map<Woman,Man> engagedTo = new TreeMap()
List<Man> freeGuys = (Man.values()).clone()
while(freeGuys) {
Man thisGuy = freeGuys[0]
freeGuys... | Give a code snippet in #Groovy
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knapsack_problem/0-1 | Knapsack problem/0-1 | A tourist wants to make a good trip at the weekend with his friends.
They will go to the mountains to see the wonders of nature, so he needs to pack well for the trip.
He has a good knapsack for carrying things, but knows that he can carry a maximum of only 4kg in it, and it will have to last the whole day.
He cre... | #Sidef | Sidef | var raw = <<'TABLE'
map, 9, 150
compass, 13, 35
water, 153, 200
sandwich, 50, 160
glucose, 15, 60
tin, 68, 45
banana, 27, 60
apple, 39, 40
cheese, 23, 30
bee... | Give a code snippet in #Sidef
A tourist wants to make a good trip at the weekend with his friends.
They will go to the mountains to see the wonders of nature, so he needs to pack well for the trip.
He has a good knapsack for carrying things, but knows that he can carry a maximum of only 4kg in it, and it will have... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Order_two_numerical_lists | Order two numerical lists | sorting
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
She... | #Aime | Aime | ordl(list a, b)
{
integer i, l, o;
l = min(~a, ~b);
i = 0;
while (i < l) {
if (a[i] != b[i]) {
o = a[i] < b[i];
break;
}
i += 1;
}
i < l ? o : ~a <= ~b;
}
main(void)
{
o_(ordl(list(1, 2), list(1, 2)), "\n");
o_(ordl(list(1e2, 2), li... | Give a code snippet in #Aime
sorting
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 |
Q... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sudoku | Sudoku | Task
Solve a partially filled-in normal 9x9 Sudoku grid and display the result in a human-readable format.
references
Algorithmics of Sudoku may help implement this.
Python Sudoku Solver Computerphile video.
| #Forth | Forth | include lib/interprt.4th
include lib/istype.4th
include lib/argopen.4th
\ ---------------------
\ Variables
\ ---------------------
81 string sudokugrid
9 array sudoku_row
9 array sudoku_col
9 array sudoku_box
\ -------------
\ 4tH interface
\ -------------
: >grid ( n2 a1 n... | Give a code snippet in #Forth
Task
Solve a partially filled-in normal 9x9 Sudoku grid and display the result in a human-readable format.
references
Algorithmics of Sudoku may help implement this.
Python Sudoku Solver Computerphile video.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Aliquot_sequence_classifications | Aliquot sequence classifications | An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications for non termination:
If the s... | #Raku | Raku | sub propdivsum (\x) {
my @l = x > 1;
(2 .. x.sqrt.floor).map: -> \d {
unless x % d { my \y = x div d; y == d ?? @l.push: d !! @l.append: d,y }
}
sum @l;
}
multi quality (0,1) { 'perfect ' }
multi quality (0,2) { 'amicable' }
multi quality (0,$n) { "sociable-$n" }
multi quality ($,1) { 'aspi... | Give a code snippet in #Raku
An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stack | Stack |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is accessed through its top.
The ba... | #Oberon-2 | Oberon-2 |
MODULE Stacks;
IMPORT
Object,
Object:Boxed,
Out := NPCT:Console;
TYPE
Pool(E: Object.Object) = POINTER TO ARRAY OF E;
Stack*(E: Object.Object) = POINTER TO StackDesc(E);
StackDesc*(E: Object.Object) = RECORD
pool: Pool(E);
cap-,top: LONGINT;
END;
PROCEDURE (s: Stack(E)) INIT*(cap: LONGINT... | Give a code snippet in #Oberon-2
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number | Guess the number | Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a "Well guessed!" message, a... | #ProDOS | ProDOS | :a
editvar /modify /value=-random-= <10
editvar /newvar /value=-random- /title=a
editvar /newvar /value=b /userinput=1 /title=Guess a number:
if -b- /hasvalue=-a- printline You guessed correctly! else printline Your guess was wrong & goto :a | Give a code snippet in #ProDOS
Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/CSV_to_HTML_translation | CSV to HTML translation | Consider a simplified CSV format where all rows are separated by a newline
and all columns are separated by commas.
No commas are allowed as field data, but the data may contain
other characters and character sequences that would
normally be escaped when converted to HTML
Task
Create a function that takes a st... | #Tcl | Tcl | package require Tcl 8.5
package require csv
package require html
package require struct::queue
set csvData "Character,Speech
The multitude,The messiah! Show us the messiah!
Brians mother,<angry>Now you listen here! He's not the messiah; he's a very naughty boy! Now go away!</angry>
The multitude,Who are you?
Brians m... | Give a code snippet in #Tcl
Consider a simplified CSV format where all rows are separated by a newline
and all columns are separated by commas.
No commas are allowed as field data, but the data may contain
other characters and character sequences that would
normally be escaped when converted to HTML
Task
Crea... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_configuration_file | Read a configuration file | The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are ignored by the application
# pr... | #Aime | Aime | record r, s;
integer c;
file f;
list l;
text an, d, k;
an = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
f.affix("tmp/config");
while ((c = f.peek) ^ -1) {
integer removed;
f.side(" \t\r");
c = f.peek;
removed = c == ';';
if (removed) {
f.pick;
f.side(" \... | Give a code snippet in #Aime
The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greyscale_bars/Display | Greyscale bars/Display | The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display.
For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of grey until we have a white bar on the right ha... | #Perl | Perl | sub partition {
my($all, $div) = @_;
my @marks = 0;
push @marks, $_/$div * $all for 1..$div;
my @copy = @marks;
$marks[$_] -= $copy[$_-1] for 1..$#marks;
@marks[1..$#marks];
}
sub bars {
my($h,$w,$p,$rev) = @_;
my (@nums,@vals,$line,$d);
$d = 2**$p;
push @nums, int $_/($d-1)... | Give a code snippet in #Perl
The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display.
For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of grey until we ha... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Aliquot_sequence_classifications | Aliquot sequence classifications | An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications for non termination:
If the s... | #Scala | Scala | def createAliquotSeq(n: Long, step: Int, list: List[Long]): (String, List[Long]) = {
val sum = properDivisors(n).sum
if (sum == 0) ("terminate", list ::: List(sum))
else if (step >= 16 || sum > 140737488355328L) ("non-term", list)
else {
list.indexOf(sum) match {
case -1 => createAli... | Give a code snippet in #Scala
An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hash_from_two_arrays | Hash from two arrays | Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| #Crystal | Crystal | keys = ('a'..'z').to_a # => a, b, c ... z
vals = (1..26).to_a # => 1, 2, 3 ... 26
hash = Hash.zip(keys, vals)
p hash | Give a code snippet in #Crystal
Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_definition | Function definition | A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract from showing how functions are ... | #Factor | Factor | : multiply ( a b -- a*b ) * ; | Give a code snippet in #Factor
A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cumulative_standard_deviation | Cumulative standard deviation | Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the function in the implementation langu... | #OCaml | OCaml | let sqr x = x *. x
let stddev l =
let n, sx, sx2 =
List.fold_left
(fun (n, sx, sx2) x -> succ n, sx +. x, sx2 +. sqr x)
(0, 0., 0.) l
in
sqrt ((sx2 -. sqr sx /. float n) /. float n)
let _ =
let l = [ 2.;4.;4.;4.;5.;5.;7.;9. ] in
Printf.printf "List: ";
List.iter (Printf.printf "%g ") l;... | Give a code snippet in #OCaml
Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the funct... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_squares | Sum of squares | Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| #PL.2FI | PL/I |
declare A(10) float initial (10, 9, 8, 7, 6, 5, 4, 3, 2, 1);
put (sum(A**2));
| Give a code snippet in #PL.2FI
Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Least_common_multiple | Least common multiple | Least common multiple
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Compute the least common multiple (LCM) of two integers.
Given m and n, the least common multiple is the smallest positive integer that has both m and n as factor... | #GAP | GAP | # Built-in
LcmInt(12, 18);
# 36 | Give a code snippet in #GAP
Least common multiple
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Compute the least common multiple (LCM) of two integers.
Given m and n, the least common multiple is the smallest positive integer that has b... | christopher/rosetta-code | |
http://rosettacode.org/wiki/RPG_attributes_generator | RPG attributes generator | RPG = Role Playing Game.
You're running a tabletop RPG, and your players are creating characters.
Each character has six core attributes: strength, dexterity, constitution, intelligence, wisdom, and charisma.
One way of generating values for these attributes is to roll four, 6-sided dice (d6) and sum the three... | #True_BASIC | True BASIC | FUNCTION min(a, b)
IF a < b THEN LET min = a ELSE LET min = b
END FUNCTION
FUNCTION d6
LET d6 = 1 + INT(RND * 6)
END FUNCTION
FUNCTION rollstat
LET a = d6
LET b = d6
LET c = d6
LET d = d6
LET rollstat = a + b + c + d - min(min(a, b), min(c, d))
END FUNCTION
DIM statnames$(6)
DATA "STR"... | Give a code snippet in #True_BASIC
RPG = Role Playing Game.
You're running a tabletop RPG, and your players are creating characters.
Each character has six core attributes: strength, dexterity, constitution, intelligence, wisdom, and charisma.
One way of generating values for these attributes is to roll four,... | 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... | #Harbour | Harbour | FOR i := 10 TO 0 STEP -1
? i
NEXT | Give a code snippet in #Harbour
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/Incr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knapsack_problem/0-1 | Knapsack problem/0-1 | A tourist wants to make a good trip at the weekend with his friends.
They will go to the mountains to see the wonders of nature, so he needs to pack well for the trip.
He has a good knapsack for carrying things, but knows that he can carry a maximum of only 4kg in it, and it will have to last the whole day.
He cre... | #Ceylon | Ceylon |
module knapsack "1.0.0" {
}
| Give a code snippet in #Ceylon
A tourist wants to make a good trip at the weekend with his friends.
They will go to the mountains to see the wonders of nature, so he needs to pack well for the trip.
He has a good knapsack for carrying things, but knows that he can carry a maximum of only 4kg in it, and it will hav... | 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]]
| #REXX | REXX | /* REXX */
ml ='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'
Do i=1 To 5
Do j=1 To 5
Parse Var ml m.i.j ml
End
End
l=''
Do i=1 To 5
Do j=1 To 5
l=l right(m.i.j,2)
End
Say l
l=''
End
sum=0
Do i=2 To 5
Do j=1 To i-1
sum=sum+m.i.j
End
End
Say 'Sum below main diag... | Give a code snippet in #REXX
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/Stack | Stack |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is accessed through its top.
The ba... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | EmptyQ[a_] := If[Length[a] == 0, True, False]
SetAttributes[Push, HoldAll];[a_, elem_] := AppendTo[a, elem]
SetAttributes[Pop, HoldAllComplete];
Pop[a_] := If[EmptyQ[a], False, b = Last[a]; Set[a, Most[a]]; b]
Peek[a_] := If[EmptyQ[a], False, Last[a]]
Example use:
stack = {};Push[stack, 1]; Push[stack, 2]; Push[stac... | Give a code snippet in #Mathematica.2FWolfram_Language
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also call... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Deepcopy | Deepcopy | Task
Demonstrate how to copy data structures containing complex heterogeneous and cyclic semantics.
This is often referred to as deep copying, and is normally required where structures are mutable and to ensure that independent copies can be manipulated without side-effects.
If this facility is not built into the la... | #OCaml | OCaml | let rec copy t =
if Obj.is_int t then t else
let tag = Obj.tag t in
if tag = Obj.double_tag then t else
if tag = Obj.closure_tag then t else
if tag = Obj.string_tag then Obj.repr (String.copy (Obj.obj t)) else
if tag = 0 || tag = Obj.double_array_tag then begin
let size = Obj.size t in
... | Give a code snippet in #OCaml
Task
Demonstrate how to copy data structures containing complex heterogeneous and cyclic semantics.
This is often referred to as deep copying, and is normally required where structures are mutable and to ensure that independent copies can be manipulated without side-effects.
If this fa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/2048 | 2048 | Task
Implement a 2D sliding block puzzle game where blocks with numbers are combined to add their values.
Rules of the game
The rules are that on each turn the player must choose a direction (up, down, left or right).
All tiles move as far as possible in that direction, some move more than others.
Two ... | #Java | Java | import java.awt.*;
import java.awt.event.*;
import java.util.Random;
import javax.swing.*;
public class Game2048 extends JPanel {
enum State {
start, won, running, over
}
final Color[] colorTable = {
new Color(0x701710), new Color(0xFFE4C3), new Color(0xfff4d3),
new Color(0xffd... | Give a code snippet in #Java
Task
Implement a 2D sliding block puzzle game where blocks with numbers are combined to add their values.
Rules of the game
The rules are that on each turn the player must choose a direction (up, down, left or right).
All tiles move as far as possible in that direction, some m... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Integer_comparison | Integer comparison |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Dc | Dc | [Use _ (underscore) as negative sign for numbers.]P []pP
[Enter two numbers to compare: ]P
? sbsa
[[greater than]]sp lb la >p
[ [less than]]sp lb la <p
[ [equal to]]sp lb la =p
la n [ is ]P P [ ]P lbn []pP
| Give a code snippet in #Dc
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
Con... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Leap_year | Leap year | Task
Determine whether a given year is a leap year in the Gregorian calendar.
See also
Leap year (wiki)
| #Raku | Raku | say "$year is a {Date.is-leap-year($year) ?? 'leap' !! 'common'} year." | Give a code snippet in #Raku
Task
Determine whether a given year is a leap year in the Gregorian calendar.
See also
Leap year (wiki)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Merge_sort | Sorting algorithms/Merge 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
... | #Raku | Raku | sub merge_sort ( @a ) {
return @a if @a <= 1;
my $m = @a.elems div 2;
my @l = flat merge_sort @a[ 0 ..^ $m ];
my @r = flat merge_sort @a[ $m ..^ @a ];
return flat @l, @r if @l[*-1] !after @r[0];
return flat gather {
take @l[0] before @r[0] ?? @l.shift !! @r.shift
while @... | Give a code snippet in #Raku
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 sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Order_disjoint_list_items | Order disjoint list items |
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
... | #Julia | Julia |
function order_disjoint{T<:AbstractArray}(m::T, n::T)
rlen = length(n)
rdis = zeros(Int, rlen)
for (i, e) in enumerate(n)
j = findfirst(m, e)
while j in rdis && j != 0
j = findnext(m, e, j+1)
end
rdis[i] = j
end
if 0 in rdis
throw(DomainError())
... | Give a code snippet in #Julia
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 so... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Delegates | Delegates | A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See also wp:Delegation pattern.
Objects ... | #Atari_Basic | Atari Basic |
10 REM DELEGATION CODE AND EXAMPLE . ATARI BASIC 2020 A. KRESS andreas.kress@hood-group.com
14 REM
15 GOTO 100:REM MAINLOOP
16 REM
20 REM DELEGATOR OBJECT
21 REM
30 IF DELEGATE THEN GOSUB DELEGATE:GOTO 56
35 REM
50 REM DELEGATOR HAS TO DO THE JOB
55 PRINT "DEFAULT IMPLEMENTATION - DONE BY DELEGATOR"
56 RETURN
60... | Give a code snippet in #Atari_Basic
A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Abstract_type | Abstract type | Abstract type is a type without instances or without definition.
For example in object-oriented programming using some languages, abstract types can be partial implementations of other types, which are to be derived there-from. An abstract type may provide implementation of some operations and/or components. Abstract ... | #Smalltalk | Smalltalk | someClass class >> isAbstract
^ true
someClass class >> new
self isAbstract ifTrue:[
^ self error:'trying to instantiate an abstract class'
].
^ super new
someClass >> method1
^ self subclassResponsibility
| Give a code snippet in #Smalltalk
Abstract type is a type without instances or without definition.
For example in object-oriented programming using some languages, abstract types can be partial implementations of other types, which are to be derived there-from. An abstract type may provide implementation of some oper... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Extensible_prime_generator | Extensible prime generator | Task
Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime.
The routine should demonstrably rely on either:
Being based on an open-ended counter set to count without upper limit other than system or programming language limits. In thi... | #PicoLisp | PicoLisp | (de prime? (N Lst)
(let S (sqrt N)
(for D Lst
(T (> D S) T)
(T (=0 (% N D)) NIL) ) ) )
(de primeseq (A B)
(let (I 1 R)
(nth
(make
(link 2)
(while (> A (inc 'I 2))
(and (prime? I (made)) (link I)) )
(setq R (length (made)))
... | Give a code snippet in #PicoLisp
Task
Write a generator of prime numbers, in order, that will automatically adjust to accommodate the generation of any reasonably high prime.
The routine should demonstrably rely on either:
Being based on an open-ended counter set to count without upper limit other than system or p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/A%2BB | A+B | A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated by space(s):
(
−
1000
≤... | #Common_Lisp | Common Lisp | (write (+ (read) (read))) | Give a code snippet in #Common_Lisp
A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, se... | christopher/rosetta-code | |
http://rosettacode.org/wiki/System_time | System time | Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
Date format
See also
Retr... | #AutoHotkey | AutoHotkey | FormatTime, t
MsgBox,% t | Give a code snippet in #AutoHotkey
Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Least_common_multiple | Least common multiple | Least common multiple
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Compute the least common multiple (LCM) of two integers.
Given m and n, the least common multiple is the smallest positive integer that has both m and n as factor... | #Smalltalk | Smalltalk | 12 lcm: 18 | Give a code snippet in #Smalltalk
Least common multiple
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Compute the least common multiple (LCM) of two integers.
Given m and n, the least common multiple is the smallest positive integer that... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Exceptions | Exceptions | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
This task is to give an example of an exception handling routine
and to "throw" a new exception.
Related task
Exceptions Through Nested Calls
| #Oz | Oz | raise sillyError end
raise slightlyLessSilly(data:42 reason:outOfMemory) end | Give a code snippet in #Oz
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
This task is to give an example of an exception handling routine
and to "throw" a new exception.
Related task
Exceptions Th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Merge_sort | Sorting algorithms/Merge 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
... | #Euphoria | Euphoria | function merge(sequence left, sequence right)
sequence result
result = {}
while length(left) > 0 and length(right) > 0 do
if compare(left[1], right[1]) <= 0 then
result = append(result, left[1])
left = left[2..$]
else
result = append(result, right[1])
... | Give a code snippet in #Euphoria
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/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
... | #Pascal | Pascal | program fizzbuzz(output);
var
i: integer;
begin
for i := 1 to 100 do
if i mod 15 = 0 then
writeln('FizzBuzz')
else if i mod 3 = 0 then
writeln('Fizz')
else if i mod 5 = 0 then
writeln('Buzz')
else
writeln(i)
end. | Give a code snippet in #Pascal
Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuz... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Same_fringe | Same fringe | Write a routine that will compare the leaves ("fringe") of two binary trees to determine whether they are the same list of leaves when visited left-to-right. The structure or balance of the trees does not matter; only the number, order, and value of the leaves is important.
Any solution is allowed here, but many compu... | #C | C | #include <stdio.h>
#include <stdlib.h>
#include <ucontext.h>
typedef struct {
ucontext_t caller, callee;
char stack[8192];
void *in, *out;
} co_t;
co_t * co_new(void(*f)(), void *data)
{
co_t * c = malloc(sizeof(*c));
getcontext(&c->callee);
c->in = data;
c->callee.uc_stack.ss_sp = c->stack;
c->callee.uc_... | Give a code snippet in #C
Write a routine that will compare the leaves ("fringe") of two binary trees to determine whether they are the same list of leaves when visited left-to-right. The structure or balance of the trees does not matter; only the number, order, and value of the leaves is important.
Any solution is a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #Nim | Nim | # Least signficant bit:
proc isOdd(i: int): bool = (i and 1) != 0
proc isEven(i: int): bool = (i and 1) == 0
# Modulo:
proc isOdd2(i: int): bool = (i mod 2) != 0
proc isEven2(i: int): bool = (i mod 2) == 0
# Bit Shifting:
proc isOdd3(n: int): bool = n != ((n shr 1) shl 1)
proc isEven3(n: int): bool = n == ((n shr 1... | Give a code snippet in #Nim
Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Isqrt_(integer_square_root)_of_X | Isqrt (integer square root) of X | Sometimes a function is needed to find the integer square root of X, where X can be a
real non─negative number.
Often X is actually a non─negative integer.
For the purposes of this task, X can be an integer or a real number, but if it
simplifies things in your computer programming language, assume... | #Python | Python | def isqrt ( x ):
q = 1
while q <= x :
q *= 4
z,r = x,0
while q > 1 :
q /= 4
t,r = z-r-q,r/2
if t >= 0 :
z,r = t,r+q
return r
print ' '.join( '%d'%isqrt( n ) for n in xrange( 66 ))
print '\n'.join( '{0:114,} = isqrt( 7^{1:3} )'.format( isqrt( 7**n ),n ... | Give a code snippet in #Python
Sometimes a function is needed to find the integer square root of X, where X can be a
real non─negative number.
Often X is actually a non─negative integer.
For the purposes of this task, X can be an integer or a real number, but if it
simplifies things in your compute... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Break | Loops/Break | Task
Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive).
If a number is 10, stop the loop after printing it, and do not generate any further numbers.
Otherwise, generate and print a second random number before restarting the loop.
If the number 10 is never gener... | #Lang5 | Lang5 | do 20 ? int dup . 10 == if break then 20 ? int . loop | Give a code snippet in #Lang5
Task
Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive).
If a number is 10, stop the loop after printing it, and do not generate any further numbers.
Otherwise, generate and print a second random number before restarting the loop.
... | 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... | #F.23 | F# | open System
let decode uri = Uri.UnescapeDataString(uri)
[<EntryPoint>]
let main argv =
printfn "%s" (decode "http%3A%2F%2Ffoo%20bar%2F")
0 | Give a code snippet in #F.23
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 f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Combinations_with_repetitions | Combinations with repetitions | The set of combinations with repetitions is computed from a set,
S
{\displaystyle S}
(of cardinality
n
{\displaystyle n}
), and a size of resulting selection,
k
{\displaystyle k}
, by reporting the sets of cardinality
k
{\displaystyle k}
where each member of those sets is chosen from
S... | #C.2B.2B | C++ |
#include <iostream>
#include <string>
#include <vector>
void print_vector(const std::vector<int> &pos,
const std::vector<std::string> &str) {
for (size_t i = 1; i < pos.size(); ++i) // offset: i:1..N
printf("%s\t", str[pos[i]].c_str()); // str: 0..N-1
printf("\n");
}
// idea: custo... | Give a code snippet in #C.2B.2B
The set of combinations with repetitions is computed from a set,
S
{\displaystyle S}
(of cardinality
n
{\displaystyle n}
), and a size of resulting selection,
k
{\displaystyle k}
, by reporting the sets of cardinality
k
{\displaystyle k}
where each member o... | christopher/rosetta-code | |
http://rosettacode.org/wiki/4-rings_or_4-squares_puzzle | 4-rings or 4-squares puzzle | 4-rings or 4-squares puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Replace a, b, c, d, e, f, and
g with the decimal
digits LOW ───► HIGH
such that the sum of the letters inside of each of the four large squares add up to
t... | #ALGOL_68 | ALGOL 68 | BEGIN
# solve the 4 rings or 4 squares puzzle #
# we need to find solutions to the equations: a + b = b + c + d = d + e + f = f + g #
# where a, b, c, d, e, f, g in lo : hi ( not necessarily unique ) #
# depending on show, the solutions will ... | Give a code snippet in #ALGOL_68
4-rings or 4-squares puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Replace a, b, c, d, e, f, and
g with the decimal
digits LOW ───► HIGH
such that the sum of the letters inside of each of ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Maze_generation | Maze generation |
This page uses content from Wikipedia. The original article was at Maze generation algorithm. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Generate and show a maze, using the simple Depth... | #Go | Go | package main
import (
"bytes"
"fmt"
"math/rand"
"time"
)
type maze struct {
c []byte // cell contents
h []byte // horizontal walls above cells
v []byte // vertical walls to the left of cells
c2 [][]byte // cells by row
h2 [][]byte // horizontal walls by row (ignore f... | Give a code snippet in #Go
This page uses content from Wikipedia. The original article was at Maze generation algorithm. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Generate and show a ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Average_loop_length | Average loop length | Let f be a uniformly-randomly chosen mapping from the numbers 1..N to the numbers 1..N (note: not necessarily a permutation of 1..N; the mapping could produce a number in more than one way or not at all). At some point, the sequence 1, f(1), f(f(1))... will contain a repetition, a number that occurring for the second t... | #Scala | Scala |
import scala.util.Random
object AverageLoopLength extends App {
val factorial: LazyList[Double] = 1 #:: factorial.zip(LazyList.from(1)).map(n => n._2 * factorial(n._2 - 1))
val results = for (n <- 1 to 20;
avg = tested(n, 1000000);
theory = expected(n)
... | Give a code snippet in #Scala
Let f be a uniformly-randomly chosen mapping from the numbers 1..N to the numbers 1..N (note: not necessarily a permutation of 1..N; the mapping could produce a number in more than one way or not at all). At some point, the sequence 1, f(1), f(f(1))... will contain a repetition, a number ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Text_processing/Max_licenses_in_use | Text processing/Max licenses in use | A company currently pays a fixed sum for the use of a particular licensed software package. In determining if it has a good deal it decides to calculate its maximum use of the software from its license management log file.
Assume the software's licensing daemon faithfully records a checkout event when a copy of the ... | #K | K | r:m@&a=x:|/a:+\{:[x[8+!3]~"OUT";1;-1]}'m:0:"mlijobs.txt";
`0:,/"Maximum simultaneous license use is ",$x;
`0:" at the following times:\n";`0:r[;14+!19] | Give a code snippet in #K
A company currently pays a fixed sum for the use of a particular licensed software package. In determining if it has a good deal it decides to calculate its maximum use of the software from its license management log file.
Assume the software's licensing daemon faithfully records a checkou... | 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,... | #Yabasic | Yabasic | a = open("passwd", "a") // Open the file for appending, i.e. what you write to the file will be appended after its initial contents.
// If the file does not exist, it will be created.
print #a "account:password:UID:GID:fullname,office,extension,homephone,email:directory:shell"
print #a "jsmith... | Give a code snippet in #Yabasic
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Newline_omission | Hello world/Newline omission | Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output.
Task
Display the string Goodbye, World! without a trailing newline.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Standard error
Hello world/Text
| #Tcl | Tcl | puts -nonewline "Goodbye, World!" | Give a code snippet in #Tcl
Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output.
Task
Display the string Goodbye, World! without a trailing newline.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Standar... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Trigonometric_functions | Trigonometric functions | Task
If your language has a library or built-in functions for trigonometry, show examples of:
sine
cosine
tangent
inverses (of the above)
using the same angle in radians and degrees.
For the non-inverse functions, each radian/degree pair should use arguments that evaluate to the same angle (that i... | #Erlang | Erlang |
Deg=45.
Rad=math:pi()/4.
math:sin(Deg * math:pi() / 180)==math:sin(Rad).
| Give a code snippet in #Erlang
Task
If your language has a library or built-in functions for trigonometry, show examples of:
sine
cosine
tangent
inverses (of the above)
using the same angle in radians and degrees.
For the non-inverse functions, each radian/degree pair should use arguments that eval... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic/Integer | Arithmetic/Integer |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Fortran | Fortran | INTEGER A, B
PRINT *, 'Type in two integer numbers separated by white space',
+ ' and press ENTER'
READ *, A, B
PRINT *, ' A + B = ', (A + B)
PRINT *, ' A - B = ', (A - B)
PRINT *, ' A * B = ', (A * B)
PRINT *, ' A / B = ', (A / B)
PRINT *, 'MOD(A,B) = ', MOD(A,B)
PRINT *
PRINT *, 'Even though... | Give a code snippet in #Fortran
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operation... | christopher/rosetta-code |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.