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/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
| #ZX_Spectrum_Basic | ZX Spectrum Basic | 10 REM The trailing semicolon prevents a newline
20 PRINT "Goodbye, World!"; | Give a code snippet in #ZX_Spectrum_Basic
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... | 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... | #Rust | Rust | use std::cmp;
struct Item {
name: &'static str,
weight: usize,
value: usize
}
fn knapsack01_dyn(items: &[Item], max_weight: usize) -> Vec<&Item> {
let mut best_value = vec![vec![0; max_weight + 1]; items.len() + 1];
for (i, it) in items.iter().enumerate() {
for w in 1 .. max_weight + 1 {... | Give a code snippet in #Rust
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/Collections | Collections | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Collections are abstractions to represent sets of values.
In statically-typed languages, the values are typically of a common data type.
Task
Create a collection, and add a fe... | #Ring | Ring |
text = list(2)
text[1] = "Hello "
text[2] = "world!"
see text[1] + text[2] + nl
| Give a code snippet in #Ring
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Collections are abstractions to represent sets of values.
In statically-typed languages, the values are typically of a common data type.
Task
Cre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/CUSIP | CUSIP |
This page uses content from Wikipedia. The original article was at CUSIP. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
A CUSIP is a nine-character alphanumeric code that identifies a North A... | #Factor | Factor | USING: combinators.short-circuit formatting kernel math
math.parser qw regexp sequences unicode ;
IN: rosetta-code.cusip
: cusip-check-digit ( seq -- n )
but-last-slice [
[ dup alpha? [ digit> ] [ "*@#" index 36 + ] if ] dip
odd? [ 2 * ] when 10 /mod +
] map-index sum 10 mod 10 swap - 10 mod ;... | Give a code snippet in #Factor
This page uses content from Wikipedia. The original article was at CUSIP. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
A CUSIP is a nine-character alphanumeri... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence:_nth_number_with_exactly_n_divisors | Sequence: nth number with exactly n divisors | Calculate the sequence where each term an is the nth that has n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
See also
OEIS:A073916
Related tasks
Sequence: smallest number greater than previous term with exactly n divisors
Sequence: smallest number with exactly n divisors | #jq | jq | def count(stream): reduce stream as $i (0; .+1);
# To maintain precision:
def power($b): . as $in | reduce range(0;$b) as $i (1; . * $in);
def primes: 2, (range(3; infinite; 2) | select(is_prime));
# divisors as an unsorted stream
def divisors:
if . == 1 then 1
else . as $n
| label $out
| range(1; $n) as ... | Give a code snippet in #jq
Calculate the sequence where each term an is the nth that has n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
See also
OEIS:A073916
Related tasks
Sequence: smallest number greater than previous term with exactly n divisors
Sequence: smallest number wi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parsing/RPN_calculator_algorithm | Parsing/RPN calculator algorithm | Task
Create a stack-based evaluator for an expression in reverse Polish notation (RPN) that also shows the changes in the stack as each individual token is processed as a table.
Assume an input of a correct, space separated, string of tokens of an RPN expression
Test with the RPN expression generated from the... | #PL.2FSQL | PL/SQL | CREATE OR REPLACE FUNCTION rpn_calc(str VARCHAR2) RETURN NUMBER AS
TYPE num_aa IS TABLE OF NUMBER INDEX BY PLS_INTEGER;
TYPE num_stack IS RECORD (a num_aa, top PLS_INTEGER DEFAULT 0);
ns num_stack;
pos1 INTEGER := 1;
pos2 INTEGER;
token VARCHAR2(100);
op2 NUMBER;
PROCEDURE push(s IN OUT NOCO... | Give a code snippet in #PL.2FSQL
Task
Create a stack-based evaluator for an expression in reverse Polish notation (RPN) that also shows the changes in the stack as each individual token is processed as a table.
Assume an input of a correct, space separated, string of tokens of an RPN expression
Test with the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gamma_function | Gamma function | Task
Implement one algorithm (or more) to compute the Gamma (
Γ
{\displaystyle \Gamma }
) function (in the real field only).
If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in/library function.
The Gamma funct... | #JavaScript | JavaScript | function gamma(x) {
var p = [0.99999999999980993, 676.5203681218851, -1259.1392167224028,
771.32342877765313, -176.61502916214059, 12.507343278686905,
-0.13857109526572012, 9.9843695780195716e-6, 1.5056327351493116e-7
];
var g = 7;
if (x < 0.5) {
return Math.PI / (Math.sin(Math... | Give a code snippet in #JavaScript
Task
Implement one algorithm (or more) to compute the Gamma (
Γ
{\displaystyle \Gamma }
) function (in the real field only).
If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Day_of_the_week | Day of the week | A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January).
Task
In what years between 2008 and 2121 will the 25th of ... | #Peloton | Peloton | <@ SAI>
<@ ITEFORLI3>2121|2008|
<@ LETVARCAP>Christmas Day|25-Dec-<@ SAYVALFOR>...</@></@>
<@ TSTDOWVARLIT>Christmas Day|1</@>
<@ IFF>
<@ SAYCAP>Christmas Day <@ SAYVALFOR>...</@> is a Sunday</@><@ SAYKEY>__Newline</@>
</@>
</@>
</@> | Give a code snippet in #Peloton
A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January).
Task
In what years betwee... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_an_object_at_a_given_address | Create an object at a given address |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Tcl | Tcl | package require critcl
# A command to 'make an integer object' and couple it to a Tcl variable
critcl::cproc linkvar {Tcl_Interp* interp char* var1} int {
int *intPtr = (int *) ckalloc(sizeof(int));
*intPtr = 0;
Tcl_LinkVar(interp, var1, (void *) intPtr, TCL_LINK_INT);
return (int) intPtr;
}
# A c... | Give a code snippet in #Tcl
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Dart | Dart | import 'dart:math';
main() {
var nuggets = List<int>.generate(101, (int index) => index);
for (int small in List<int>.generate((100 ~/ (6 + 1)), (int index) => index)) {
for (int medium in List<int>.generate((100 ~/ (9 + 1)), (int index) => index)) {
for (int large in List<int>.generate((100 ~/ (20 + 1)),... | Give a code snippet in #Dart
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/Faulhaber%27s_formula | Faulhaber's formula | In mathematics, Faulhaber's formula, named after Johann Faulhaber, expresses the sum of the p-th powers of the first n positive integers as a (p + 1)th-degree polynomial function of n, the coefficients involving Bernoulli numbers.
Task
Generate the first 10 closed-form expressions, starting with p = 0.
R... | #D | D | import std.algorithm : fold;
import std.exception : enforce;
import std.format : formattedWrite;
import std.numeric : cmp, gcd;
import std.range : iota;
import std.stdio;
import std.traits;
auto abs(T)(T val)
if (isNumeric!T) {
if (val < 0) {
return -val;
}
return val;
}
struct Frac {
long n... | Give a code snippet in #D
In mathematics, Faulhaber's formula, named after Johann Faulhaber, expresses the sum of the p-th powers of the first n positive integers as a (p + 1)th-degree polynomial function of n, the coefficients involving Bernoulli numbers.
Task
Generate the first 10 closed-form expressions... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Carmichael_3_strong_pseudoprimes | Carmichael 3 strong pseudoprimes | A lot of composite numbers can be separated from primes by Fermat's Little Theorem, but there are some that completely confound it.
The Miller Rabin Test uses a combination of Fermat's Little Theorem and Chinese Division Theorem to overcome this.
The purpose of this task is to investigate such numbers using a met... | #Icon_and_Unicon | Icon and Unicon | link "factors"
procedure main(A)
n := integer(!A) | 61
every write(carmichael3(!n))
end
procedure carmichael3(p1)
every (isprime(p1), (h := 1+!(p1-1)), (d := !(h+p1-1))) do
if (mod(((h+p1)*(p1-1)),d) = 0, mod((-p1*p1),h) = mod(d,h)) then {
p2 := 1 + (p1-1)*(h+p1)/d
p3 := ... | Give a code snippet in #Icon_and_Unicon
A lot of composite numbers can be separated from primes by Fermat's Little Theorem, but there are some that completely confound it.
The Miller Rabin Test uses a combination of Fermat's Little Theorem and Chinese Division Theorem to overcome this.
The purpose of this task i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Keyboard_input/Flush_the_keyboard_buffer | Keyboard input/Flush the keyboard buffer | Flush the keyboard buffer.
This reads characters from the keyboard input and
discards them until there are no more currently buffered,
and then allows the program to continue.
The program must not wait for users to type anything.
| #Kotlin | Kotlin | // version 1.0.6
fun main(args: Array<String>) {
while (System.`in`.available() > 0) System.`in`.read()
println("Goodbye!")
} | Give a code snippet in #Kotlin
Flush the keyboard buffer.
This reads characters from the keyboard input and
discards them until there are no more currently buffered,
and then allows the program to continue.
The program must not wait for users to type anything.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #Seed7 | Seed7 | $ include "seed7_05.s7i";
const proc: main is func
local
var file: aFile is STD_NULL;
var string: line is "";
begin
aFile := open("input.txt", "r");
while hasNext(aFile) do
readln(aFile, line);
writeln("LINE: " <& line);
end while;
end func; | Give a code snippet in #Seed7
Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Window_management | Window management | Treat windows or at least window identities as first class objects.
Store window identities in variables, compare them for equality.
Provide examples of performing some of the following:
hide,
show,
close,
minimize,
maximize,
move, and
resize a window.
The window of interest may or may not have b... | #PicoLisp | PicoLisp | $ ersatz/pil +
: (setq
JFrame "javax.swing.JFrame"
MAXIMIZED_BOTH (java (public JFrame 'MAXIMIZED_BOTH))
ICONIFIED (java (public JFrame 'ICONIFIED))
Win (java JFrame T "Window") )
-> $JFrame
# Compare for equality
: (== Win Win)
-> T
# Set window visible
(java Win 'setLocation 10... | Give a code snippet in #PicoLisp
Treat windows or at least window identities as first class objects.
Store window identities in variables, compare them for equality.
Provide examples of performing some of the following:
hide,
show,
close,
minimize,
maximize,
move, and
resize a window.
The window... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parsing/RPN_to_infix_conversion | Parsing/RPN to infix conversion | Parsing/RPN to infix conversion
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a program that takes an RPN representation of an expression formatted as a space separated sequence of tokens and generates the equivalent expression in infix notation.... | #Ruby | Ruby | rpn = RPNExpression.new("3 4 2 * 1 5 - 2 3 ^ ^ / +")
infix = rpn.to_infix
ruby = rpn.to_ruby | Give a code snippet in #Ruby
Parsing/RPN to infix conversion
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a program that takes an RPN representation of an expression formatted as a space separated sequence of tokens and generates the equivalent... | 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... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | toGrayscale[rgb_Image] := ImageApply[#.{0.2126, 0.7152, 0.0722}&, rgb]
toFakeRGB[L_Image] := ImageApply[{#, #, #}&, L] | Give a code snippet in #Mathematica_.2F_Wolfram_Language
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 f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hunt_the_Wumpus | Hunt the Wumpus | 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.
Create a simple implementation of the classic textual game Hunt The Wumpus.
The rules are:
The game is set in a cave that consists ... | #M2000_Interpreter | M2000 Interpreter |
Module WumpusGame {
Print "Game: Hunt The Wumpus"
Arrows=5
Dim Room(1 to 20)
Room(1)=(2,6,5),(3,8,1),(4,10,2),(5,2,3),(1,14,4)
Room(6)=(15,1,7),(17,6,8),(7,2,9),(18,8,10),(9,3,11)
Room(11)=(19,10,12),(11,4,13),(20,12,14),(5,11,13), (6,16,14)
Room(16)=(20,15,17),(16,7,18),(17,... | Give a code snippet in #M2000_Interpreter
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.
Create a simple implementation of the classic textual game Hunt The Wumpus.
The rules are... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Calculating_the_value_of_e | Calculating the value of e | Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| #Befunge | Befunge | 52*92*1->01p:01g1-:v v *_$101p011p54*21p>:11g1+:01g*01p:11p/21g1-:v v <
^ _$$>\:^ ^ p12_$>+\:#^_$554**/@ | Give a code snippet in #Befunge
Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
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
... | #Octave | Octave |
input=[1 2 6 4 2 32 5 5 4 3 3 5 1 2 32 4 4];
output=unique(input);
| Give a code snippet in #Octave
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/Yellowstone_sequence | Yellowstone sequence | The Yellowstone sequence, also called the Yellowstone permutation, is defined as:
For n <= 3,
a(n) = n
For n >= 4,
a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and
is not relatively prime to a(n-2).
The sequence is a permutation of the natural n... | #C | C | #include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
typedef struct lnode_t {
struct lnode_t *prev;
struct lnode_t *next;
int v;
} Lnode;
Lnode *make_list_node(int v) {
Lnode *node = malloc(sizeof(Lnode));
if (node == NULL) {
return NULL;
}
node->v = v;
node->prev = NU... | Give a code snippet in #C
The Yellowstone sequence, also called the Yellowstone permutation, is defined as:
For n <= 3,
a(n) = n
For n >= 4,
a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and
is not relatively prime to a(n-2).
The sequence is a p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Address_of_a_variable | Address of a variable |
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 |... | #Nim | Nim | var x = 12
var xptr = addr(x) # Get address of variable
echo cast[int](xptr) # and print it
xptr = cast[ptr int](0xFFFE) # Set the address | Give a code snippet in #Nim
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Thiele%27s_interpolation_formula | Thiele's interpolation formula |
This page uses content from Wikipedia. The original article was at Thiele's interpolation formula. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Thiele's interpolation formula is an interpolation ... | #J | J |
span =: {. - {: NB. head - tail
spans =: span\ NB. apply span to successive infixes
| Give a code snippet in #J
This page uses content from Wikipedia. The original article was at Thiele's interpolation formula. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Thiele's interpolation f... | 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... | #Haskell | Haskell | import Data.List
import Control.Monad
perms :: (Eq a) => [a] -> [[a]]
perms [] = [[]]
perms xs = [ x:xr | x <- xs, xr <- perms (xs\\[x]) ]
combs :: (Eq a) => Int -> [a] -> [[a]]
combs 0 _ = [[]]
combs n xs = [ x:xr | x <- xs, xr <- combs (n-1) xs ]
ringCheck :: [Int] -> Bool
ringCheck [x0, x1, x2, x3, x4, x5, x6]... | Give a code snippet in #Haskell
4-rings or 4-squares puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Replace a, b, c, d, e, f, and
g with the decimal
digits LOW ───► HIGH
such that the sum of the letters inside of each of t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/List_comprehensions | List comprehensions | A list comprehension is a special syntax in some programming languages to describe lists. It is similar to the way mathematicians describe sets, with a set comprehension, hence the name.
Some attributes of a list comprehension are:
They should be distinct from (nested) for loops and the use of map and filter functio... | #Rust | Rust | fn pyth(n: u32) -> impl Iterator<Item = [u32; 3]> {
(1..=n).flat_map(move |x| {
(x..=n).flat_map(move |y| {
(y..=n).filter_map(move |z| {
if x.pow(2) + y.pow(2) == z.pow(2) {
Some([x, y, z])
} else {
None
}
... | Give a code snippet in #Rust
A list comprehension is a special syntax in some programming languages to describe lists. It is similar to the way mathematicians describe sets, with a set comprehension, hence the name.
Some attributes of a list comprehension are:
They should be distinct from (nested) for loops and the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #Stata | Stata | clear all
set obs 1000
gen x=rnormal(1,0.5) | Give a code snippet in #Stata
Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Permutations | Permutations | Task
Write a program that generates all permutations of n different objects. (Practically numerals!)
Related tasks
Find the missing permutation
Permutations/Derangements
The number of samples of size k from n objects.
With combinations and permutations generation tasks.
Order Uni... | #Modula-2 | Modula-2 | MODULE Permute;
FROM Terminal
IMPORT Read, Write, WriteLn;
FROM Terminal2
IMPORT WriteString;
CONST MAXIDX = 6;
MINIDX = 1;
TYPE TInpCh = ['a'..'z'];
TChr = SET OF TInpCh;
VAR n,
nl: INTEGER;
ch: CHAR;
a: ARRAY[MINIDX..MAXIDX] OF CHAR;
kt: TChr = TChr{'a'..'f'};
PROCEDURE output;
VAR i: INTEGER... | Give a code snippet in #Modula-2
Task
Write a program that generates all permutations of n different objects. (Practically numerals!)
Related tasks
Find the missing permutation
Permutations/Derangements
The number of samples of size k from n objects.
With combinations and permutations g... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Yin_and_yang | Yin and yang | One well-known symbol of the philosophy of duality known as yin and yang is the taijitu.
Task
Create a function that, given a parameter representing size, generates such a symbol scaled to the requested size.
Generate and display the symbol for two different (small) sizes.
| #Quackery | Quackery | [ $ "turtleduck.qky" loadfile ] now!
[ -1 4 turn
2dup -v fly
1 4 turn
4 wide
' [ 0 0 0 ] colour
' [ 0 0 0 ] fill
[ 2dup 2 1 v/ 1 2 arc
2dup -2 1 v/ 1 2 arc
2dup -v 1 2 arc ]
2dup -v 1 2 arc
1 4 turn
2dup 2 1 v/ fly
' [ 0 0 0 ] colour
1 wide
' [ 25... | Give a code snippet in #Quackery
One well-known symbol of the philosophy of duality known as yin and yang is the taijitu.
Task
Create a function that, given a parameter representing size, generates such a symbol scaled to the requested size.
Generate and display the symbol for two different (small) sizes.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Line_printer | Hello world/Line printer | Task
Cause a line printer attached to the computer to print a line containing the message: Hello World!
Note
A line printer is not the same as standard output.
A line printer was an older-style printer which prints one line at a time to a continuous ream of paper.
With some systems, a line printer can be... | #C.23 | C# |
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
public class DOCINFOA
{
[MarshalAs(UnmanagedType.LPStr)]
public string pDocName;
[MarshalAs(UnmanagedType.LPStr)]
public string pOutputFile;
[MarshalAs(UnmanagedType.LPStr)]
public string pDataType;
}
[DllImport("winspool.Drv", En... | Give a code snippet in #C.23
Task
Cause a line printer attached to the computer to print a line containing the message: Hello World!
Note
A line printer is not the same as standard output.
A line printer was an older-style printer which prints one line at a time to a continuous ream of paper.
With some ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Priority_queue | Priority queue | A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insert... | #J | J | coclass 'priorityQueue'
PRI=: ''
QUE=: ''
insert=:4 :0
p=. PRI,x
q=. QUE,y
assert. p -:&$ q
assert. 1 = #$q
ord=: \: p
QUE=: ord { q
PRI=: ord { p
i.0 0
)
topN=:3 :0
assert y<:#PRI
r=. y{.QUE
PRI=: y}.PRI
QUE=: y}.QUE
r
) | Give a code snippet in #J
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Humble_numbers | Humble numbers | Humble numbers are positive integers which have no prime factors > 7.
Humble numbers are also called 7-smooth numbers, and sometimes called highly composite,
although this conflicts with another meaning of highly composite numbers.
Another way to express the above is:
humble = 2i × 3j × 5k... | #Nim | Nim | import sets, strformat
proc min[T](s: HashSet[T]): T =
## Return the minimal value in a set.
if s.card == 0:
raise newException(ValueError, "set is empty.")
result = T.high
for n in s:
if n < result: result = n
iterator humbleNumbers(): Positive =
## Yield the successive humble numbers.
var ... | Give a code snippet in #Nim
Humble numbers are positive integers which have no prime factors > 7.
Humble numbers are also called 7-smooth numbers, and sometimes called highly composite,
although this conflicts with another meaning of highly composite numbers.
Another way to express the above i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/99_bottles_of_beer | 99 bottles of beer | Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
98 bottles of beer
Take one dow... | #mIRC_Scripting_Language | mIRC Scripting Language | var %x = 99
while (%x) {
echo -ag %x bottles of beer on the wall
echo -ag %x bottles of beer
echo -ag Take one down, pass it around
dec %x
echo -ag %x bottles of beer on the wall
} | Give a code snippet in #mIRC_Scripting_Language
Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of bee... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sieve_of_Eratosthenes | Sieve of Eratosthenes | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed... | #Frink | Frink |
n = eval[input["Enter highest number: "]]
results = array[sieve[n]]
println[results]
println[length[results] + " prime numbers less than or equal to " + n]
sieve[n] :=
{
// Initialize array
array = array[0 to n]
array@1 = 0
for i = 2 to ceil[sqrt[n]]
if array@i != 0
for j = i^2 to n ste... | Give a code snippet in #Frink
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes a... | 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 ... | #Wren | Wren | var bc = Fn.new { |p|
var c = List.filled(p+1, 0)
var r = 1
var half = (p/2).floor
for (i in 0..half) {
c[i] = r
c[p-i] = r
r = (r * (p-i) / (i+1)).floor
}
var j = p - 1
while (j >= 0) {
c[j] = -c[j]
j = j - 2
}
return c
}
var e = "²³⁴⁵⁶⁷".co... | Give a code snippet in #Wren
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/15_puzzle_game | 15 puzzle game |
Task
Implement the Fifteen Puzzle Game.
The 15-puzzle is also known as:
Fifteen Puzzle
Gem Puzzle
Boss Puzzle
Game of Fifteen
Mystic Square
14-15 Puzzle
and some others.
Related Tasks
15 Puzzle Solver
16 Puzzle Game
| #PHP | PHP | <?php
// Puzzle 15 Game - Rosseta Code - PHP 7 as the server-side script language.
// This program DOES NOT use cookies.
session_start([
"use_only_cookies" => 0,
"use_cookies" => 0,
"use_trans_sid" => 1,
]);
class Location
{
protected $column, $row;
function __construct($column, $row){
$this->colu... | Give a code snippet in #PHP
Task
Implement the Fifteen Puzzle Game.
The 15-puzzle is also known as:
Fifteen Puzzle
Gem Puzzle
Boss Puzzle
Game of Fifteen
Mystic Square
14-15 Puzzle
and some others.
Related Tasks
15 Puzzle Solver
16 Puzzle Game
| christopher/rosetta-code | |
http://rosettacode.org/wiki/One-dimensional_cellular_automata | One-dimensional cellular automata | Assume an array of cells with an initial distribution of live and dead cells,
and imaginary cells off the end of the array having fixed values.
Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the current generation.
If, in the follow... | #MontiLang | MontiLang | 30 VAR length .
35 VAR height .
FOR length 0 ENDFOR 1 0 ARR VAR list .
length 1 - VAR topLen .
FOR topLen 0 ENDFOR 1 ARR VAR topLst .
DEF getNeighbors
1 - VAR tempIndex .
GET tempIndex SWAP
tempIndex 1 + VAR tempIndex .
GET tempIndex SWAP
tempIndex 1 + VAR tempIndex .
GET tempIndex SWAP... | Give a code snippet in #MontiLang
Assume an array of cells with an initial distribution of live and dead cells,
and imaginary cells off the end of the array having fixed values.
Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the cur... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ackermann_function | Ackermann function | The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
n
+
1
if
m
=
0
A
(
m
... | #Objeck | Objeck | class Ackermann {
function : Main(args : String[]) ~ Nil {
for(m := 0; m <= 3; ++m;) {
for(n := 0; n <= 4; ++n;) {
a := Ackermann(m, n);
if(a > 0) {
"Ackermann({$m}, {$n}) = {$a}"->PrintLine();
};
};
};
}
function : Ackermann(m : Int, n : Int) ~ Int {
if... | Give a code snippet in #Objeck
The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Safe_primes_and_unsafe_primes | Safe primes and unsafe primes | Definitions
A safe prime is a prime p and where (p-1)/2 is also prime.
The corresponding prime (p-1)/2 is known as a Sophie Germain prime.
An unsafe prime is a prime p and where (p-1)/2 isn't a prime.
An unsafe prime is a prime that isn't a safe prime.
Task
... | #Perl | Perl | use ntheory qw(forprimes is_prime);
my $upto = 1e7;
my %class = ( safe => [], unsafe => [2] );
forprimes {
push @{$class{ is_prime(($_-1)>>1) ? 'safe' : 'unsafe' }}, $_;
} 3, $upto;
for (['safe', 35], ['unsafe', 40]) {
my($type, $quantity) = @$_;
print "The first $quantity $type primes are:\n";
p... | Give a code snippet in #Perl
Definitions
A safe prime is a prime p and where (p-1)/2 is also prime.
The corresponding prime (p-1)/2 is known as a Sophie Germain prime.
An unsafe prime is a prime p and where (p-1)/2 isn't a prime.
An unsafe prime is a prime that isn't... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Rust | Rust | extern crate rand;
use rand::{ThreadRng, thread_rng};
use rand::distributions::{IndependentSample, Range};
use std::collections::HashSet;
use std::env;
use std::process;
fn help() {
println!("usage: average_loop_length <max_N> <trials>");
}
fn main() {
let args: Vec<String> = env::args().collect();
le... | Give a code snippet in #Rust
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 t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Keyboard_input/Obtain_a_Y_or_N_response | Keyboard input/Obtain a Y or N response |
Task
Obtain a valid Y or N response from the keyboard.
The keyboard should be flushed, so that any outstanding key-presses are removed, preventing any existing Y or N key-press from being evaluated.
The response should be obtained as soon as Y or N are pressed, and there should be no need t... | #QUACKASM | QUACKASM |
; Stores result in cell 2; 1 if yes, 0 if no.
:YORN
PRINT YORNMSG
:YORN1
INPUT >2
AND *2,$5F,'Y >2 /YORN2
AND *2,,'N \YORN1
:YORN2
PRINTC *2
PRINTC 13
AND *2,1 >2
RETURN
:YORNMSG " (Y/N)? \
| Give a code snippet in #QUACKASM
Task
Obtain a valid Y or N response from the keyboard.
The keyboard should be flushed, so that any outstanding key-presses are removed, preventing any existing Y or N key-press from being evaluated.
The response should be obtained as soon as Y or N are pres... | 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... | #Python | Python | def lookandsay(number):
result = ""
repeat = number[0]
number = number[1:]+" "
times = 1
for actual in number:
if actual != repeat:
result += str(times)+repeat
times = 1
repeat = actual
else:
times += 1
return result
num = "... | Give a code snippet in #Python
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/Introspection | Introspection | Task
verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old.
check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop).
Extra credit
Repor... | #PowerBASIC | PowerBASIC | #COMPILER PBWIN 9
#COMPILER PBWIN, PBCC 5 | Give a code snippet in #PowerBASIC
Task
verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old.
check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes comput... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Longest_common_subsequence | Longest common subsequence | Introduction
Define a subsequence to be any output string obtained by deleting zero or more symbols from an input string.
The Longest Common Subsequence (LCS) is a subsequence of maximum length common to two or more strings.
Let A ≡ A[0]… A[m - 1] and B ≡ B[0]… B[n - 1], m < n be strings drawn from an alphabet Σ of ... | #PureBasic | PureBasic | Procedure.s lcs(a$, b$)
Protected x$ , lcs$
If Len(a$) = 0 Or Len(b$) = 0
lcs$ = ""
ElseIf Right(a$, 1) = Right(b$, 1)
lcs$ = lcs(Left(a$, Len(a$) - 1), Left(b$, Len(b$) - 1)) + Right(a$, 1)
Else
x$ = lcs(a$, Left(b$, Len(b$) - 1))
y$ = lcs(Left(a$, Len(a$) - 1), b$)
If Len(x$) > Len(y$)
... | Give a code snippet in #PureBasic
Introduction
Define a subsequence to be any output string obtained by deleting zero or more symbols from an input string.
The Longest Common Subsequence (LCS) is a subsequence of maximum length common to two or more strings.
Let A ≡ A[0]… A[m - 1] and B ≡ B[0]… B[n - 1], m < n be s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_carpet | Sierpinski carpet | Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ... | #APL | APL | carpet←{{⊃⍪/,⌿3 3⍴4 0 4\⊂⍵}⍣⍵⊢⍪'#'} | Give a code snippet in #APL
Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## #... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_comments_from_a_string | Strip comments from a string | Strip comments from a string
You are encouraged to solve this task according to the task description, using any language you may know.
The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line.
Whitespace debacle: There is s... | #Lua | Lua | comment_symbols = ";#"
s1 = "apples, pears # and bananas"
s2 = "apples, pears ; and bananas"
print ( string.match( s1, "[^"..comment_symbols.."]+" ) )
print ( string.match( s2, "[^"..comment_symbols.."]+" ) ) | Give a code snippet in #Lua
Strip comments from a string
You are encouraged to solve this task according to the task description, using any language you may know.
The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line.
Whi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Super-d_numbers | Super-d numbers | A super-d number is a positive, decimal (base ten) integer n such that d × nd has at least d consecutive digits d where
2 ≤ d ≤ 9
For instance, 753 is a super-3 number because 3 × 7533 = 1280873331.
Super-d numbers are also shown on MathWorld™ as super-d or super-d.
Task
Write a... | #jq | jq | # To take advantage of gojq's arbitrary-precision integer arithmetic:
def power($b): . as $in | reduce range(0;$b) as $i (1; . * $in);
# Input is $d, the number of consecutive digits, 2 <= $d <= 9
# $max is the number of superd numbers to be emitted.
def superd($number):
. as $d
| tostring as $s
| ($s * $d) as ... | Give a code snippet in #jq
A super-d number is a positive, decimal (base ten) integer n such that d × nd has at least d consecutive digits d where
2 ≤ d ≤ 9
For instance, 753 is a super-3 number because 3 × 7533 = 1280873331.
Super-d numbers are also shown on MathWorld™ as super-d or ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_element_of_a_list | Greatest element of a list | Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| #VBA | VBA | Option Explicit
Sub Main()
Dim a
a = Array(1, 15, 19, 25, 13, 0, -125, 9)
Debug.Print Max_VBA(a)
End Sub
Function Max_VBA(Arr As Variant) As Long
Dim i As Long, temp As Long
temp = Arr(LBound(Arr))
For i = LBound(Arr) + 1 To UBound(Arr)
If Arr(i) > temp Then temp = Arr(i)
Next i
Max_VBA = te... | Give a code snippet in #VBA
Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| 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... | #Forth | Forth | : prime? ( n -- ? ) here + c@ 0= ;
: notprime! ( n -- ) here + 1 swap c! ;
: prime_sieve { n -- }
here n erase
0 notprime!
1 notprime!
n 4 > if
n 4 do i notprime! 2 +loop
then
3
begin
dup dup * n <
while
dup prime? if
n over dup * do
i notprime!
dup 2* +loop
then
... | Give a code snippet in #Forth
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 prim... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multiplication_tables | Multiplication tables | Task
Produce a formatted 12×12 multiplication table of the kind memorized by rote when in primary (or elementary) school.
Only print the top half triangle of products.
| #Excel | Excel | FNOVERHALFCARTESIANPRODUCT
=LAMBDA(f,
LAMBDA(n,
LET(
ixs, SEQUENCE(n, n, 1, 1),
REM, "1-based indices.",
x, 1 + MOD(ixs - 1, n),
y, 1 + QUOTIENT(ixs - 1, n),
IF(x >= y,
f(x)(y),
""
)
)
)
) | Give a code snippet in #Excel
Task
Produce a formatted 12×12 multiplication table of the kind memorized by rote when in primary (or elementary) school.
Only print the top half triangle of products.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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.
| #F.23 | F# | module SudokuBacktrack
//Helpers
let tuple2 a b = a,b
let flip f a b = f b a
let (>>=) f g = Option.bind g f
/// "A1" to "I9" squares as key in values dictionary
let key a b = $"{a}{b}"
/// Cross product of elements in ax and elements in bx
let cross ax bx = [| for a in ax do for b in bx do key a b |]
// const... | Give a code snippet in #F.23
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/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #min | min | ("" split reverse "" join) :reverse-str | Give a code snippet in #min
Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Abbreviations,_simple | Abbreviations, simple | The use of abbreviations (also sometimes called synonyms, nicknames, AKAs, or aliases) can be an
easy way to add flexibility when specifying or using commands, sub─commands, options, etc.
For this task, the following command table will be used:
add 1 alter 3 backup 2 bottom 1 Cappend 2 change 1 ... | #C | C | #include <ctype.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
const char* command_table =
"add 1 alter 3 backup 2 bottom 1 Cappend 2 change 1 Schange Cinsert 2 Clast 3 "
"compress 4 copy 2 count 3 Coverlay 3 cursor 3 delete 3 Cdelete 2 down 1 duplicate "
"3 xEdit ... | Give a code snippet in #C
The use of abbreviations (also sometimes called synonyms, nicknames, AKAs, or aliases) can be an
easy way to add flexibility when specifying or using commands, sub─commands, options, etc.
For this task, the following command table will be used:
add 1 alter 3 backup 2 bott... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Reduced_row_echelon_form | Reduced row echelon form | Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(for most languages, this wil... | #D | D | import std.stdio, std.algorithm, std.array, std.conv;
void toReducedRowEchelonForm(T)(T[][] M) pure nothrow @nogc {
if (M.empty)
return;
immutable nrows = M.length;
immutable ncols = M[0].length;
size_t lead;
foreach (immutable r; 0 .. nrows) {
if (ncols <= lead)
retu... | Give a code snippet in #D
Reduced row echelon form
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Show how to compute the reduced row echelon form
(a.k.a. row canonical form) of a matrix.
The matrix can be stored in any datatype that is convenient
(f... | 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... | #MUMPS | MUMPS | ISHAPPY(N)
;Determines if a number N is a happy number
;Note that the returned strings do not have a leading digit unless it is a happy number
IF (N'=N\1)!(N<0) QUIT "Not a positive integer"
NEW SUM,I
;SUM is the sum of the square of each digit
;I is a loop variable
;SEQ is the sequence of previously checked SUM... | Give a code snippet in #MUMPS
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determinant_and_permanent | Determinant and permanent | For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while the permanent is given by
... | #Kotlin | Kotlin | // version 1.1.2
typealias Matrix = Array<DoubleArray>
fun johnsonTrotter(n: Int): Pair<List<IntArray>, List<Int>> {
val p = IntArray(n) { it } // permutation
val q = IntArray(n) { it } // inverse permutation
val d = IntArray(n) { -1 } // direction = 1 or -1
var sign = 1
val perms = mutableLi... | Give a code snippet in #Kotlin
For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while ... | 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... | #UNIX_Shell | UNIX Shell | #!/bin/bash
function sum_of_square_digits
{
local -i n="$1" sum=0
while (( n )); do
local -i d=n%10
let sum+=d*d
let n=n/10
done
echo "$sum"
}
function is_happy?
{
local -i n="$1"
local seen=()
while (( n != 1 )); do
if [ -n "${seen[$n]}" ]; then
return 1
fi
seen[n]... | Give a code snippet in #UNIX_Shell
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 endle... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Evolutionary_algorithm | Evolutionary algorithm | Starting with:
The target string: "METHINKS IT IS LIKE A WEASEL".
An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent).
A fitness function that computes the ‘closeness’ of its argument to the target string.... | #Ceylon | Ceylon | import ceylon.random {
DefaultRandom
}
shared void run() {
value mutationRate = 0.05;
value childrenPerGeneration = 100;
value target = "METHINKS IT IS LIKE A WEASEL";
value alphabet = {' ', *('A'..'Z')};
value random = DefaultRandom();
value randomLetter => random.nextElement(alphabet);
function fitn... | Give a code snippet in #Ceylon
Starting with:
The target string: "METHINKS IT IS LIKE A WEASEL".
An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent).
A fitness function that computes the ‘closeness’ of it... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Euler%27s_constant_0.5772... | Euler's constant 0.5772... |
Task.
Compute the Euler constant 0.5772...
Discovered by Leonhard Euler around 1730, it is the most ubiquitous mathematical constant after pi and e, but appears more arcane than these.
Denoted gamma (γ), it measures the amount by which the partial sums of the harmonic series (the simplest diverging series) differ f... | #Ruby | Ruby | n = 1e6
p (1..n).sum{ 1.0/_1 } - Math.log(n) | Give a code snippet in #Ruby
Task.
Compute the Euler constant 0.5772...
Discovered by Leonhard Euler around 1730, it is the most ubiquitous mathematical constant after pi and e, but appears more arcane than these.
Denoted gamma (γ), it measures the amount by which the partial sums of the harmonic series (the simpl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Comments | Comments | Task
Show all ways to include text in a language source file
that's completely ignored by the compiler or interpreter.
Related tasks
Documentation
Here_document
See also
Wikipedia
xkcd (Humor: hand gesture denoting // for "commenting out" people.)
| #Hope | Hope | ! All Hope comments begin with "!" and extend to the end of the line | Give a code snippet in #Hope
Task
Show all ways to include text in a language source file
that's completely ignored by the compiler or interpreter.
Related tasks
Documentation
Here_document
See also
Wikipedia
xkcd (Humor: hand gesture denoting // for "commenting out" people.)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Display_an_extended_character | Terminal control/Display an extended character | Task
Display an extended (non ASCII) character onto the terminal.
Specifically, display a £ (GBP currency sign).
| #Perl | Perl | use feature 'say';
# OK as is
say '￡';
# these need 'binmode needed to surpress warning about 'wide' char
binmode STDOUT, ":utf8";
say "\N{FULLWIDTH POUND SIGN}";
say "\x{FFE1}";
say chr 0xffe1; | Give a code snippet in #Perl
Task
Display an extended (non ASCII) character onto the terminal.
Specifically, display a £ (GBP currency sign).
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Resistor_mesh | Resistor mesh |
Task
Given 10×10 grid nodes (as shown in the image) interconnected by 1Ω resistors as shown,
find the resistance between points A and B.
See also
(humor, nerd sniping) xkcd.com cartoon
| #C | C | #include <stdio.h>
#include <stdlib.h>
#define S 10
typedef struct { double v; int fixed; } node;
#define each(i, x) for(i = 0; i < x; i++)
node **alloc2(int w, int h)
{
int i;
node **a = calloc(1, sizeof(node*)*h + sizeof(node)*w*h);
each(i, h) a[i] = i ? a[i-1] + w : (node*)(a + h);
return a;
}
void set_bou... | Give a code snippet in #C
Task
Given 10×10 grid nodes (as shown in the image) interconnected by 1Ω resistors as shown,
find the resistance between points A and B.
See also
(humor, nerd sniping) xkcd.com cartoon
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Draw_a_cuboid | Draw a cuboid | Task
Draw a cuboid with relative dimensions of 2 × 3 × 4.
The cuboid can be represented graphically, or in ASCII art, depending on the language capabilities.
To fulfill the criteria of being a cuboid, three faces must be visible.
Either static or rotational projection is acceptable for this task.
R... | #POV-Ray | POV-Ray | camera { perspective location <2.6,2.2,-4.2> look_at <0,-.5,0>
aperture .05 blur_samples 100 variance 1/100000 focal_point <2,1,-2>}
light_source{< 60,20,-20> color rgb 2}
sky_sphere { pigment{ gradient z color_map{[0 rgb 0.3][.1 rgb <.7,.8,1>][1 rgb .2]} }}
box { <0,0,0> <3,2,4>
texture {
pigment... | Give a code snippet in #POV-Ray
Task
Draw a cuboid with relative dimensions of 2 × 3 × 4.
The cuboid can be represented graphically, or in ASCII art, depending on the language capabilities.
To fulfill the criteria of being a cuboid, three faces must be visible.
Either static or rotational projection ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call | Exceptions/Catch an exception thrown in a nested call | Show how to create a user-defined exception and show how to catch an exception raised from several nested calls away.
Create two user-defined exceptions, U0 and U1.
Have function foo call function bar twice.
Have function bar call function baz.
Arrange for function baz to rais... | #TXR | TXR | @(defex u0)
@(defex u1)
@(define baz (x))
@ (cases)
@ (bind x "0")
@ (throw u0 "text0")
@ (or)
@ (bind x "1")
@ (throw u1 "text1")
@ (end)
@(end)
@(define bar (x))
@ (baz x)
@(end)
@(define foo ())
@ (next :list @'("0" "1"))
@ (collect)
@num
@ (try)
@ (bar num)
@ (catch u0 (arg))
@ (ou... | Give a code snippet in #TXR
Show how to create a user-defined exception and show how to catch an exception raised from several nested calls away.
Create two user-defined exceptions, U0 and U1.
Have function foo call function bar twice.
Have function bar call function baz.
Arrange... | 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... | #APL | APL | ∇ ret←RLL rll;count
[1] count←∣2-/((1,(2≠/rll),1)×⍳1+⍴rll)~0
[2] ret←(⍕count,¨(1,2≠/rll)/rll)~' '
∇
| Give a code snippet in #APL
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 functi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/GUI_enabling/disabling_of_controls | GUI enabling/disabling of controls | In addition to fundamental GUI component interaction, an application should
dynamically enable and disable GUI components, to give some guidance to the
user, and prohibit (inter)actions which are inappropriate in the current state
of the application.
Task
Similar to the task GUI component interaction, write a progr... | #BaCon | BaCon | OPTION GUI TRUE
PRAGMA GUI gtk3
gui = GUIDEFINE(" \
{ type=WINDOW name=window callback=delete-event title=\"Rosetta Code\" width-request=200 } \
{ type=BOX name=box parent=window orientation=GTK_ORIENTATION_VERTICAL } \
{ type=SPIN_BUTTON name=spin parent=box numeric=TRUE } \
{ type=BUTTON_BOX name=bb... | Give a code snippet in #BaCon
In addition to fundamental GUI component interaction, an application should
dynamically enable and disable GUI components, to give some guidance to the
user, and prohibit (inter)actions which are inappropriate in the current state
of the application.
Task
Similar to the task GUI compo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Memory_allocation | Memory allocation | Task
Show how to explicitly allocate and deallocate blocks of memory in your language.
Show access to different types of memory (i.e., heap, stack, shared, foreign) if applicable.
| #COBOL | COBOL | PROGRAM-ID. memory-allocation.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 based-data PIC X(20) VALUE "Hello, World!"
BASED.
PROCEDURE DIVISION.
*> INITIALIZED sets the data item to the VALUE.
ALLOCATE based-dat... | Give a code snippet in #COBOL
Task
Show how to explicitly allocate and deallocate blocks of memory in your language.
Show access to different types of memory (i.e., heap, stack, shared, foreign) if applicable.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Binary_search | Binary search | A binary search divides a range of values into halves, and continues to narrow down the field of search until the unknown value is found. It is the classic example of a "divide and conquer" algorithm.
As an analogy, consider the children's game "guess a number." The scorer has a secret number, and will only tell the p... | #Standard_ML | Standard ML | fun binary_search cmp (key, arr) =
let
fun aux slice =
if ArraySlice.isEmpty slice then
NONE
else
let
val mid = ArraySlice.length slice div 2
in
case cmp (ArraySlice.sub (slice, mid), key)
of LESS => aux (ArraySlice.subslice (slice, mid+1, NONE))
| GREATER => ... | Give a code snippet in #Standard_ML
A binary search divides a range of values into halves, and continues to narrow down the field of search until the unknown value is found. It is the classic example of a "divide and conquer" algorithm.
As an analogy, consider the children's game "guess a number." The scorer has a se... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For_with_a_specified_step | Loops/For with a specified step |
Task
Demonstrate a for-loop where the step-value is greater than one.
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 b... | #DWScript | DWScript | var i : Integer;
for i := 2 to 8 step 2 do
PrintLn(i); | Give a code snippet in #DWScript
Task
Demonstrate a for-loop where the step-value is greater than one.
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/... | 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.
| #HicEst | HicEst | FUNCTION zero_divide(num, denom)
XEQ( num// "/" // denom, *99) ! on error jump to label 99
zero_divide = 0 ! division OK
RETURN
99 zero_divide = 1
END | Give a code snippet in #HicEst
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/Arena_storage_pool | Arena storage pool | Dynamically allocated objects take their memory from a heap.
The memory for an object is provided by an allocator which maintains the storage pool used for the heap.
Often a call to allocator is denoted as
P := new T
where T is the type of an allocated object, and P is a reference to the object.
The stora... | #Scala | Scala | package require Tcl 8.6
oo::class create Pool {
superclass oo::class
variable capacity pool busy
unexport create
constructor args {
next {*}$args
set capacity 100
set pool [set busy {}]
}
method new {args} {
if {[llength $pool]} {
set pool [lassign $pool obj]
} else {
if {[llength... | Give a code snippet in #Scala
Dynamically allocated objects take their memory from a heap.
The memory for an object is provided by an allocator which maintains the storage pool used for the heap.
Often a call to allocator is denoted as
P := new T
where T is the type of an allocated object, and P is a refe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Julia_set | Julia set |
Task
Generate and draw a Julia set.
Related tasks
Mandelbrot Set
| #Processing | Processing |
float cX = -0.7;
float cY = 0.27015;
float zx, zy;
float maxIter = 300;
void setup() {
size(640, 480);
}
void draw() {
for (int x = 0; x < width; x++) {
for (int y = 0; y < height; y++) {
zx = 1.5 * (x - width / 2) / (0.5 * width);
zy = (y - height / 2) / (0.5 * height);
float i = maxIte... | Give a code snippet in #Processing
Task
Generate and draw a Julia set.
Related tasks
Mandelbrot Set
| 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... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | semiPrimeQ[n_Integer] := Module[{factors, numfactors},
factors = FactorInteger[n] // Transpose;
numfactors = factors[[2]] // Total ;
numfactors == 2
] | Give a code snippet in #Mathematica.2FWolfram_Language
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 ... | 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.
| #Groovy | Groovy | def varname = 'foo'
def value = 42
new GroovyShell(this.binding).evaluate("${varname} = ${value}")
assert foo == 42 | Give a code snippet in #Groovy
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/Multiple_regression | Multiple regression | Task
Given a set of data vectors in the following format:
y
=
{
y
1
,
y
2
,
.
.
.
,
... | #Racket | Racket |
#lang racket
(require math)
(define T matrix-transpose)
(define (fit X y)
(matrix-solve (matrix* (T X) X) (matrix* (T X) y)))
| Give a code snippet in #Racket
Task
Given a set of data vectors in the following format:
y
=
{
y
1
,
y
2
,
.
.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/9_billion_names_of_God_the_integer | 9 billion names of God the integer | This task is a variation of the short story by Arthur C. Clarke.
(Solvers should be aware of the consequences of completing this task.)
In detail, to specify what is meant by a “name”:
The integer 1 has 1 name “1”.
The integer 2 has 2 names “1+1”, and “2”.
The integer 3 has 3 names “1+1+1”, “2+1”, ... | #zkl | zkl | var [const] BN=Import.lib("zklBigNum");
const N=0d100_000;
p:=List.createLong(N+1,BN.fp(0),True); // (0,0,...) all different
fcn calc(n,p){
p[n].set(0); // reset array for each run
foreach k in ([1..n]){
d:=n - k *(3*k - 1)/2;
do(2){
if (d<0) break(2);
if (k.isOdd) p[n].add(p[d]);
e... | Give a code snippet in #zkl
This task is a variation of the short story by Arthur C. Clarke.
(Solvers should be aware of the consequences of completing this task.)
In detail, to specify what is meant by a “name”:
The integer 1 has 1 name “1”.
The integer 2 has 2 names “1+1”, and “2”.
The integer 3 has 3... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Line_printer | Hello world/Line printer | Task
Cause a line printer attached to the computer to print a line containing the message: Hello World!
Note
A line printer is not the same as standard output.
A line printer was an older-style printer which prints one line at a time to a continuous ream of paper.
With some systems, a line printer can be... | #Salmon | Salmon | open_output_text_file("/dev/lp0").print("Hello World!"); | Give a code snippet in #Salmon
Task
Cause a line printer attached to the computer to print a line containing the message: Hello World!
Note
A line printer is not the same as standard output.
A line printer was an older-style printer which prints one line at a time to a continuous ream of paper.
With som... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Infinite | Loops/Infinite | Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within l... | #HicEst | HicEst | DO i = 1, 1E20 ! for i with 16 or more digits: i == i + 1 == loop infinite
WRITE() "SPAM"
ENDDO | Give a code snippet in #HicEst
Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-decimal_radices/Input | Non-decimal radices/Input | It is common to have a string containing a number written in some format, with the most common ones being decimal, hexadecimal, octal and binary. Such strings are found in many places (user interfaces, configuration files, XML data, network protocols, etc.)
This task requires parsing of such a string (which may be ass... | #J | J | baseN=: (, 'b'&,)&.": | Give a code snippet in #J
It is common to have a string containing a number written in some format, with the most common ones being decimal, hexadecimal, octal and binary. Such strings are found in many places (user interfaces, configuration files, XML data, network protocols, etc.)
This task requires parsing of such... | 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... | #Go | Go | package main
import (
"fmt"
"sync"
)
func ambStrings(ss []string) chan []string {
c := make(chan []string)
go func() {
for _, s := range ss {
c <- []string{s}
}
close(c)
}()
return c
}
func ambChain(ss []string, cIn chan []string) chan []string {
cOu... | Give a code snippet in #Go
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").... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Scope/Function_names_and_labels | Scope/Function names and labels | Task
Explain or demonstrate the levels of visibility of function names and labels within the language.
See also
Variables for levels of scope relating to visibility of program variables
Scope modifiers for general scope modification facilities
| #Ruby | Ruby |
def welcome(name)
puts "hello #{name}"
end
puts "What is your name?"
$name = STDIN.gets
welcome($name)
return | Give a code snippet in #Ruby
Task
Explain or demonstrate the levels of visibility of function names and labels within the language.
See also
Variables for levels of scope relating to visibility of program variables
Scope modifiers for general scope modification facilities
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_a_series | Sum of a series | Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1
n
1
k
2
{\displa... | #Rust | Rust | const LOWER: i32 = 1;
const UPPER: i32 = 1000;
// Because the rule for our series is simply adding one, the number of terms are the number of
// digits between LOWER and UPPER
const NUMBER_OF_TERMS: i32 = (UPPER + 1) - LOWER;
fn main() {
// Formulaic method
println!("{}", (NUMBER_OF_TERMS * (LOWER + UPPER)) /... | Give a code snippet in #Rust
Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-continuous_subsequences | Non-continuous subsequences | Consider some sequence of elements. (It differs from a mere set of elements by having an ordering among members.)
A subsequence contains some subset of the elements of this sequence, in the same order.
A continuous subsequence is one in which no elements are missing between the first and last elements of the subseque... | #Raku | Raku | sub non_continuous_subsequences ( *@list ) {
@list.combinations.grep: { 1 != all( .[ 0 ^.. .end] Z- .[0 ..^ .end] ) }
}
say non_continuous_subsequences( 1..3 )».gist;
say non_continuous_subsequences( 1..4 )».gist;
say non_continuous_subsequences( ^4 ).map: {[<a b c d>[.list]].gist}; | Give a code snippet in #Raku
Consider some sequence of elements. (It differs from a mere set of elements by having an ordering among members.)
A subsequence contains some subset of the elements of this sequence, in the same order.
A continuous subsequence is one in which no elements are missing between the first and... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Evolutionary_algorithm | Evolutionary algorithm | Starting with:
The target string: "METHINKS IT IS LIKE A WEASEL".
An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent).
A fitness function that computes the ‘closeness’ of its argument to the target string.... | #Common_Lisp | Common Lisp | (defun fitness (string target)
"Closeness of string to target; lower number is better"
(loop for c1 across string
for c2 across target
count (char/= c1 c2)))
(defun mutate (string chars p)
"Mutate each character of string with probablity p using characters from chars"
(dotimes (n (length strin... | Give a code snippet in #Common_Lisp
Starting with:
The target string: "METHINKS IT IS LIKE A WEASEL".
An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent).
A fitness function that computes the ‘closeness’ ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Currying | Currying |
This page uses content from Wikipedia. The original article was at Currying. 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
Create a simple demonstrative example of Currying in a specific la... | #Lua | Lua |
function curry2(f)
return function(x)
return function(y)
return f(x,y)
end
end
end
function add(x,y)
return x+y
end
local adder = curry2(add)
assert(adder(3)(4) == 3+4)
local add2 = adder(2)
assert(add2(3) == 2+3)
assert(add2(5) == 2+5)
| Give a code snippet in #Lua
This page uses content from Wikipedia. The original article was at Currying. 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
Create a simple demonstrative example... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gauss-Jordan_matrix_inversion | Gauss-Jordan matrix inversion | Task
Invert matrix A using Gauss-Jordan method.
A being an n × n matrix.
| #Haskell | Haskell | isMatrix xs = null xs || all ((== (length.head $ xs)).length) xs
isSquareMatrix xs = null xs || all ((== (length xs)).length) xs
mult:: Num a => [[a]] -> [[a]] -> [[a]]
mult uss vss = map ((\xs -> if null xs then [] else foldl1 (zipWith (+)) xs). zipWith (\vs u -> map (u*) vs) vss) uss
matI::(Num a) => Int -> [[a... | Give a code snippet in #Haskell
Task
Invert matrix A using Gauss-Jordan method.
A being an n × n matrix.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Tau_function | Tau function | Given a positive integer, count the number of its positive divisors.
Task
Show the result for the first 100 positive integers.
Related task
Tau number
| #BASIC | BASIC | 10 DEFINT A-Z
20 FOR I=1 TO 100
30 N=I: GOSUB 100
40 PRINT USING " ##";T;
50 IF I MOD 20=0 THEN PRINT
60 NEXT
70 END
100 T=1
110 IF (N AND 1)=0 THEN N=N\2: T=T+1: GOTO 110
120 P=3
130 GOTO 180
140 C=1
150 IF N MOD P=0 THEN N=N\P: C=C+1: GOTO 150
160 T=T*C
170 P=P+2
180 IF P*P<=N GOTO 140
190 IF N>1 THEN T=T*2
200 RETUR... | Give a code snippet in #BASIC
Given a positive integer, count the number of its positive divisors.
Task
Show the result for the first 100 positive integers.
Related task
Tau number
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Map_range | Map range | Given two ranges:
[
a
1
,
a
2
]
{\displaystyle [a_{1},a_{2}]}
and
[
b
1
,
b
2
]
{\displaystyle [b_{1},b_{2}]}
;
then a value
s
{\displaystyle s}
in range
[
a
1
,
a
2
]
{\displaystyle [a_{1},a_{2}]}
is linearly mapped to a value
t
{\di... | #AutoHotkey | AutoHotkey |
mapRange(a1, a2, b1, b2, s)
{
return b1 + (s-a1)*(b2-b1)/(a2-a1)
}
out := "Mapping [0,10] to [-1,0] at intervals of 1:`n"
Loop 11
out .= "f(" A_Index-1 ") = " mapRange(0,10,-1,0,A_Index-1) "`n"
MsgBox % out
| Give a code snippet in #AutoHotkey
Given two ranges:
[
a
1
,
a
2
]
{\displaystyle [a_{1},a_{2}]}
and
[
b
1
,
b
2
]
{\displaystyle [b_{1},b_{2}]}
;
then a value
s
{\displaystyle s}
in range
[
a
1
,
a
2
]
{\displaystyle [a_{1},a_{2}]}
is linea... | 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... | #Isabelle | Isabelle | theory Scratch
imports Main
begin
section‹100 Doors›
datatype doorstate = Open | Closed
fun toggle :: "doorstate ⇒ doorstate" where
"toggle Open = Closed"
| "toggle Closed = Open"
fun walk :: "('a ⇒ 'a) ⇒ nat ⇒ nat ⇒ 'a list ⇒ 'a list" where
"walk f _ _ [] = []"
| "walk f eve... | Give a code snippet in #Isabelle
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/Sorting_algorithms/Strand_sort | Sorting algorithms/Strand 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
... | #Tcl | Tcl | proc merge {listVar toMerge} {
upvar 1 $listVar v
set i [set j 0]
set out {}
while {$i<[llength $v] && $j<[llength $toMerge]} {
if {[set a [lindex $v $i]] < [set b [lindex $toMerge $j]]} {
lappend out $a
incr i
} else {
lappend out $b
incr j
}
}
# Done the merge, but will ... | Give a code snippet in #Tcl
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Haskell | Haskell | import Control.Monad (when)
main = loop 1024
where loop n = when (n > 0)
(do print n
loop (n `div` 2)) | Give a code snippet in #Haskell
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/Downw... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Generator/Exponential | Generator/Exponential | A generator is an executable entity (like a function or procedure) that contains code that yields a sequence of values, one at a time, so that each time you call the generator, the next value in the sequence is provided.
Generators are often built on top of coroutines or objects so that the internal state of the objec... | #XPL0 | XPL0 | code ChOut=8, IntOut=11;
func Gen(M); \Generate Mth powers of positive integers
int M;
int N, R, I;
[N:= [0, 0, 0, 0]; \provides own/static variables
R:= 1;
for I:= 1 to M do R:= R*N(M);
N(M):= N(M)+1;
return R;
];
func Filter; \Generate squares of positive integers that aren't cubes
in... | Give a code snippet in #XPL0
A generator is an executable entity (like a function or procedure) that contains code that yields a sequence of values, one at a time, so that each time you call the generator, the next value in the sequence is provided.
Generators are often built on top of coroutines or objects so that t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Minimum_positive_multiple_in_base_10_using_only_0_and_1 | Minimum positive multiple in base 10 using only 0 and 1 | Every positive integer has infinitely many base-10 multiples that only use the digits 0 and 1. The goal of this task is to find and display the minimum multiple that has this property.
This is simple to do, but can be challenging to do efficiently.
To avoid repeating long, unwieldy phrases, the operation "minimum pos... | #Perl | Perl | use strict;
use warnings;
use Math::AnyNum qw(:overload as_bin digits2num);
for my $x (1..10, 95..105, 297, 576, 594, 891, 909, 999) {
my $y;
if ($x =~ /^9+$/) { $y = digits2num([(1) x (9 * length $x)],2) } # all 9's implies all 1's
else { while (1) { last unless as_bin(++$y) % $x } }
pr... | Give a code snippet in #Perl
Every positive integer has infinitely many base-10 multiples that only use the digits 0 and 1. The goal of this task is to find and display the minimum multiple that has this property.
This is simple to do, but can be challenging to do efficiently.
To avoid repeating long, unwieldy phras... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Remove_lines_from_a_file | Remove lines from a file | Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remove the first two lines from th... | #Clojure | Clojure | (require '[clojure.java.io :as jio]
'[clojure.string :as str])
(defn remove-lines1 [filepath start nskip]
(let [lines (str/split-lines (slurp filepath))
new-lines (concat (take (dec start) lines)
(drop (+ (dec start) nskip) lines))
diff (- (count lines) (count new-... | Give a code snippet in #Clojure
Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to r... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Textonyms | Textonyms | When entering text on a phone's digital pad it is possible that a particular combination of digits corresponds to more than one word. Such are called textonyms.
Assuming the digit keys are mapped to letters as follows:
2 -> ABC
3 -> DEF
4 -> GHI
5 -> JKL
6 -> MNO
7 -> PQRS
8 -> TUV
9 -... | #Java | Java |
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Scanner;
import java.util.Vector;
public class RTextonyms {
private static... | Give a code snippet in #Java
When entering text on a phone's digital pad it is possible that a particular combination of digits corresponds to more than one word. Such are called textonyms.
Assuming the digit keys are mapped to letters as follows:
2 -> ABC
3 -> DEF
4 -> GHI
5 -> JKL
6 -> MNO
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Polynomial_long_division | Polynomial long division |
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In algebra, polynomial long division is an algorithm for d... | #C.2B.2B | C++ |
#include <iostream>
#include <iterator>
#include <vector>
using namespace std;
typedef vector<double> Poly;
// does: prints all members of vector
// input: c - ASCII char with the name of the vector
// A - reference to polynomial (vector)
void Print(char name, const Poly &A) {
cout << name << "(" << A.si... | Give a code snippet in #C.2B.2B
This page uses content from Wikipedia. The original article was at Polynomial long division. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In algebra, polynomial lo... | 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... | #Nim | Nim | proc `<`[T](a, b: openarray[T]): bool =
for i in 0 .. min(a.len, b.len):
if a[i] < b[i]: return true
if a[i] > b[i]: return false
return a.len < b.len
echo([1,2,1,3,2] < [1,2,0,4,4,0,0,0]) | Give a code snippet in #Nim
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 |
Qu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Menu | Menu | Task
Given a prompt and a list containing a number of strings of which one is to be selected, create a function that:
prints a textual menu formatted as an index value followed by its corresponding string for each item in the list;
prompts the user to enter a number;
returns the string corresponding to the selecte... | #BASIC | BASIC | FUNCTION sel$(choices$(), prompt$)
IF UBOUND(choices$) - LBOUND(choices$) = 0 THEN sel$ = ""
ret$ = ""
DO
FOR i = LBOUND(choices$) TO UBOUND(choices$)
PRINT i; ": "; choices$(i)
NEXT i
INPUT ;prompt$, index
IF index <= UBOUND(choices$) AND index >= LBOUND(choices$) THEN ret$ =... | Give a code snippet in #BASIC
Task
Given a prompt and a list containing a number of strings of which one is to be selected, create a function that:
prints a textual menu formatted as an index value followed by its corresponding string for each item in the list;
prompts the user to enter a number;
returns the stri... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Align_columns | Align columns | Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either left
justified, right justified, o... | #Swift | Swift | import Foundation
extension String {
func dropLastIf(_ char: Character) -> String {
if last == char {
return String(dropLast())
} else {
return self
}
}
}
enum Align {
case left, center, right
}
func getLines(input: String) -> [String] {
input
.components(separatedBy: "\n")
... | Give a code snippet in #Swift
Given a text file of many lines, where fields within a line
are delineated by a single 'dollar' character, write a program
that aligns each column of fields by ensuring that words in each
column are separated by at least one space.
Further, allow for each word in a column to be either lef... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Bubble_sort | Sorting algorithms/Bubble sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #PARI.2FGP | PARI/GP | bubbleSort(v)={
for(i=1,#v-1,
for(j=i+1,#v,
if(v[j]<v[i],
my(t=v[j]);
v[j]=v[i];
v[i]=t
)
)
);
v
}; | Give a code snippet in #PARI.2FGP
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/P-value_correction | P-value correction | Given a list of p-values, adjust the p-values for multiple comparisons. This is done in order to control the false positive, or Type 1 error rate.
This is also known as the "false discovery rate" (FDR). After adjustment, the p-values will be higher but still inside [0,1].
The adjusted p-values are sometimes called "q... | #SAS | SAS | data pvalues;
input raw_p @@;
cards;
4.533744e-01 7.296024e-01 9.936026e-02 9.079658e-02 1.801962e-01
8.752257e-01 2.922222e-01 9.115421e-01 4.355806e-01 5.324867e-01
4.926798e-01 5.802978e-01 3.485442e-01 7.883130e-01 2.729308e-01
8.502518e-01 4.268138e-01 6.442008e-01 3.030266e-01 5.001555e-02
3.194810e-01 7.892933e-... | Give a code snippet in #SAS
Given a list of p-values, adjust the p-values for multiple comparisons. This is done in order to control the false positive, or Type 1 error rate.
This is also known as the "false discovery rate" (FDR). After adjustment, the p-values will be higher but still inside [0,1].
The adjusted p-v... | christopher/rosetta-code |
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