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
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|---|---|---|---|---|---|---|---|---|
http://rosettacode.org/wiki/Sleeping_Beauty_problem | Sleeping Beauty problem | Background on the task
In decision theory, The Sleeping Beauty Problem
is a problem invented by Arnold Zoboff and first publicized on Usenet. The experimental
subject, named Sleeping Beauty, agrees to an experiment as follows:
Sleeping Beauty volunteers to be put into a deep sleep on a Sunday. There is then a fair coin... | #Ruby | Ruby | def sleeping_beauty_experiment(n)
coin = [:heads, :tails]
gotheadsonwaking = 0
wakenings = 0
n.times do
wakenings += 1
coin.sample == :heads ? gotheadsonwaking += 1 : wakenings += 1
end
puts "Wakenings over #{n} experiments: #{wakenings}"
gotheadsonwaking / wakenings.to_f
end
puts "Results of ex... | Give a code snippet in #Ruby
Background on the task
In decision theory, The Sleeping Beauty Problem
is a problem invented by Arnold Zoboff and first publicized on Usenet. The experimental
subject, named Sleeping Beauty, agrees to an experiment as follows:
Sleeping Beauty volunteers to be put into a deep sleep on a Sun... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Linear_congruential_generator | Linear congruential generator | The linear congruential generator is a very simple example of a random number generator.
All linear congruential generators use this formula:
r
n
+
1
=
a
×
r
n
+
c
(
mod
m
)
{\displaystyle r_{n+1}=a\times r_{n}+c{\pmod {m}}}
Where:
r
0
{\displaystyle r_{0}}
is a seed.
r
1
... | #Wren | Wren | import "/big" for BigInt
import "/fmt" for Fmt
// basic linear congruential generator
var lcg = Fn.new { |a, c, m, seed|
var r = BigInt.new(seed)
return Fn.new {
r = (r*a + c) % m
return r
}
}
// Microsoft generator has extra division step
var msg = Fn.new { |seed|
var g = lcg.call(2... | Give a code snippet in #Wren
The linear congruential generator is a very simple example of a random number generator.
All linear congruential generators use this formula:
r
n
+
1
=
a
×
r
n
+
c
(
mod
m
)
{\displaystyle r_{n+1}=a\times r_{n}+c{\pmod {m}}}
Where:
r
0
{\displaystyle r_... | 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.
| #PicoLisp | PicoLisp | (load "lib/simul.l")
### Fields/Board ###
# val lst
(setq
*Board (grid 9 9)
*Fields (apply append *Board) )
# Init values to zero (empty)
(for L *Board
(for This L
(=: val 0) ) )
# Build lookup lists
(for (X . L) *Board
(for (Y . This) L
(=: lst
(make
(let A (* 3 (/ ... | Give a code snippet in #PicoLisp
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/Reflection/List_methods | Reflection/List methods | Task
The goal is to get the methods of an object, as names, values or both.
Some languages offer dynamic methods, which in general can only be inspected if a class' public API includes a way of listing them.
| #Factor | Factor | USING: io math prettyprint see ;
"The list of methods contained in the generic word + :" print
\ + methods . nl
"The list of methods specializing on the fixnum class:" print
fixnum methods . | Give a code snippet in #Factor
Task
The goal is to get the methods of an object, as names, values or both.
Some languages offer dynamic methods, which in general can only be inspected if a class' public API includes a way of listing them.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Magic_constant | Magic constant | A magic square is a square grid containing consecutive integers from 1 to N², arranged so that every row, column and diagonal adds up to the same number. That number is a constant. There is no way to create a valid N x N magic square that does not sum to the associated constant.
EG
A 3 x 3 magic square always sums to ... | #Arturo | Arturo | a: function [n][
n: n+2
return (n*(1 + n^2))/2
]
aInv: function [x][
k: new 0
while [x > 2 + k*(1+k^2)/2]
-> inc 'k
return k
]
print "The first 20 magic constants are:"
print map 1..19 => a
print ""
print "The 1,000th magic constant is:"
print a 1000
print ""
loop 1..19 'z ->
print... | Give a code snippet in #Arturo
A magic square is a square grid containing consecutive integers from 1 to N², arranged so that every row, column and diagonal adds up to the same number. That number is a constant. There is no way to create a valid N x N magic square that does not sum to the associated constant.
EG
A 3 ... | 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... | #Stata | Stata | ssc install qqvalue | Give a code snippet in #Stata
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rosetta_Code/Count_examples | Rosetta Code/Count examples | task
Essentially, count the number of occurrences of =={{header| on each task page.
Output:
100 doors: 20 examples.
99 Bottles of Beer: 29 examples.
Abstract type: 10 examples.
Total: X examples.
For a full output, updated periodically, see Rosetta Code/Count examples/Full list.
You'll need to use the Media Wiki AP... | #Tcl | Tcl | package require Tcl 8.5
package require http
package require json
fconfigure stdout -buffering none
proc get_tasks {category} {
set start [clock milliseconds]
puts -nonewline "getting $category members..."
set base_url http://www.rosettacode.org/w/api.php
set query {action query list categorymembers... | Give a code snippet in #Tcl
task
Essentially, count the number of occurrences of =={{header| on each task page.
Output:
100 doors: 20 examples.
99 Bottles of Beer: 29 examples.
Abstract type: 10 examples.
Total: X examples.
For a full output, updated periodically, see Rosetta Code/Count examples/Full list.
You'll ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Permutations/Derangements | Permutations/Derangements | A derangement is a permutation of the order of distinct items in which no item appears in its original place.
For example, the only two derangements of the three items (0, 1, 2) are (1, 2, 0), and (2, 0, 1).
The number of derangements of n distinct items is known as the subfactorial of n, sometimes written as !n.
The... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language |
Needs["Combinatorica`"]
derangements[n_] := Derangements[Range[n]]
derangements[4]
Table[{NumberOfDerangements[i], Subfactorial[i]}, {i, 9}] // TableForm
Subfactorial[20] | Give a code snippet in #Mathematica.2FWolfram_Language
A derangement is a permutation of the order of distinct items in which no item appears in its original place.
For example, the only two derangements of the three items (0, 1, 2) are (1, 2, 0), and (2, 0, 1).
The number of derangements of n distinct items is know... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Conditional_structures | Conditional structures | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Common conditional structures include ... | #Octave | Octave | if (condition)
% body
endif
if (condition)
% body
else
% otherwise body
endif
if (condition1)
% body
elseif (condition2)
% body 2
else
% otherwise body
endif | Give a code snippet in #Octave
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Common... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Execute_a_system_command | Execute a system command | Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| #JavaScript | JavaScript | var shell = new ActiveXObject("WScript.Shell");
shell.run("cmd /c dir & pause"); | Give a code snippet in #JavaScript
Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Patience_sort | Sorting algorithms/Patience 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
... | #C | C |
#include<stdlib.h>
#include<stdio.h>
int* patienceSort(int* arr,int size){
int decks[size][size],i,j,min,pickedRow;
int *count = (int*)calloc(sizeof(int),size),*sortedArr = (int*)malloc(size*sizeof(int));
for(i=0;i<size;i++){
for(j=0;j<size;j++){
if(count[j]==0 || (count[j]>0 && decks[j][count[j]-1]>=ar... | Give a code snippet in #C
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Singly-linked_list/Element_insertion | Singly-linked list/Element insertion | Singly-Linked List (element)
singly-linked list
Using this method, insert an element C into a list comprised of elements A->B, following element A.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Trav... | #OCaml | OCaml | let rec insert_after a b = function
c :: cs when a = c -> a :: b :: cs
| c :: cs -> c :: insert_after a b cs
| [] -> raise Not_found | Give a code snippet in #OCaml
Singly-Linked List (element)
singly-linked list
Using this method, insert an element C into a list comprised of elements A->B, following element A.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definitio... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Phrase_reversals | Phrase reversals | Task
Given a string of space separated words containing the following phrase:
rosetta code phrase reversal
Reverse the characters of the string.
Reverse the characters of each individual word in the string, maintaining original word order within the string.
Reverse the order of each word of the string, maintaini... | #Scala | Scala | object PhraseReversals extends App {
val phrase = scala.io.StdIn.readLine
println(phrase.reverse)
println(phrase.split(' ').map(_.reverse).mkString(" "))
println(phrase.split(' ').reverse.mkString(" "))
} | Give a code snippet in #Scala
Task
Given a string of space separated words containing the following phrase:
rosetta code phrase reversal
Reverse the characters of the string.
Reverse the characters of each individual word in the string, maintaining original word order within the string.
Reverse the order of eac... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Brownian_tree | Brownian tree | Brownian tree
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw a Brownian Tree.
A Brownian Tree is generated as a result of an initial seed, followed by the interaction of two processes.
The initial "seed" is placed somewhere wi... | #Fantom | Fantom |
using fwt
using gfx
class Main
{
public static Void main ()
{
particles := Particles (300, 200)
1000.times { particles.addParticle } // add 1000 particles
Window // open up a display for the final tree
{
title = "Brownian Tree"
EdgePane
{
center = ScrollPane { content... | Give a code snippet in #Fantom
Brownian tree
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw a Brownian Tree.
A Brownian Tree is generated as a result of an initial seed, followed by the interaction of two processes.
The initi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/French_Republican_calendar | French Republican calendar | Write a program to convert dates between the Gregorian calendar and the French Republican calendar.
The year 1 of the Republican calendar began on 22 September 1792. There were twelve months (Vendémiaire, Brumaire, Frimaire, Nivôse, Pluviôse, Ventôse, Germinal, Floréal, Prairial, Messidor, Thermidor, and Fructidor) of... | #Wren | Wren | import "/date" for Date
import "/seq" for Lst
import "/fmt" for Fmt
class FrenchRCDate {
/* uses the 'continuous method' for years after 1805 */
static isLeapYear(y) {
var yy = y + 1
return (yy % 4 == 0) && (yy % 100 != 0 || yy % 400 == 0)
}
static parse(frcDate) {
var split... | Give a code snippet in #Wren
Write a program to convert dates between the Gregorian calendar and the French Republican calendar.
The year 1 of the Republican calendar began on 22 September 1792. There were twelve months (Vendémiaire, Brumaire, Frimaire, Nivôse, Pluviôse, Ventôse, Germinal, Floréal, Prairial, Messidor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Set | Set |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an... | #Wren | Wren | import "/set" for Set
var fruits = Set.new(["apple", "pear", "orange", "banana"])
System.print("fruits : %(fruits)")
var fruits2 = Set.new(["melon", "orange", "lemon", "gooseberry"])
System.print("fruits2 : %(fruits2)\n")
System.print("fruits contains 'banana' : %(fruits.contains("banana"))")
System.print("fr... | Give a code snippet in #Wren
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set cr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Integer_sequence | Integer sequence | Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations limits. For example, if integer... | #Plain_English | Plain English | To run:
Start up.
Put 1 into a number.
Loop.
Convert the number to a string.
Write the string to the console.
Bump the number.
Repeat.
Shut down. | Give a code snippet in #Plain_English
Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Primality_by_trial_division | Primality by trial division | Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loops are allowed.
Related tasks
... | #Sidef | Sidef | func is_prime(a) {
given (a) {
when (2) { true }
case (a <= 1 || a.is_even) { false }
default { 3 .. a.isqrt -> any { .divides(a) } -> not }
}
} | Give a code snippet in #Sidef
Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loops... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Singly-linked_list/Traversal | Singly-linked list/Traversal | Traverse from the beginning of a singly-linked list to the end.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked ... | #Retro | Retro | : traverse ( l- ) repeat @ 0; again ; | Give a code snippet in #Retro
Traverse from the beginning of a singly-linked list to the end.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ... | #Cat | Cat | define fib {
dup 1 <=
[]
[dup 1 - fib swap 2 - fib +]
if
} | Give a code snippet in #Cat
The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are g... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Literals/String | Literals/String | Task
Show literal specification of characters and strings.
If supported, show how the following work:
verbatim strings (quotes where escape sequences are quoted literally)
here-strings
Also, discuss which quotes expand variables.
Related tasks
Special characters
Here document
Other tasks r... | #FreeBASIC | FreeBASIC |
Print "Hello, World."
Print Chr(34); "Hello, World." & Chr(34)
Print "Tom said, ""The fox ran away."""
Print "Tom said," + "'The fox ran away.'"
| Give a code snippet in #FreeBASIC
Task
Show literal specification of characters and strings.
If supported, show how the following work:
verbatim strings (quotes where escape sequences are quoted literally)
here-strings
Also, discuss which quotes expand variables.
Related tasks
Special character... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Anti-primes | Anti-primes | The anti-primes
(or highly composite numbers, sequence A002182 in the OEIS)
are the natural numbers with more factors than any smaller than itself.
Task
Generate and show here, the first twenty anti-primes.
Related tasks
Factors of an integer
Sieve of Eratosthenes
| #Cowgol | Cowgol | include "cowgol.coh";
const AMOUNT := 20;
sub countFactors(n: uint16): (count: uint16) is
var i: uint16 := 1;
count := 1;
while i <= n/2 loop
if n%i == 0 then
count := count + 1;
end if;
i := i + 1;
end loop;
end sub;
var max: uint16 := 0;
var seen: uint8 := 0;
va... | Give a code snippet in #Cowgol
The anti-primes
(or highly composite numbers, sequence A002182 in the OEIS)
are the natural numbers with more factors than any smaller than itself.
Task
Generate and show here, the first twenty anti-primes.
Related tasks
Factors of an integer
Sieve of Eratosthenes
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Copy_stdin_to_stdout | Copy stdin to stdout | Create an executable file that copies stdin to stdout, or else a script that does so through the invocation of an interpreter at the command line.
| #sed | sed |
sed -e ''
| Give a code snippet in #sed
Create an executable file that copies stdin to stdout, or else a script that does so through the invocation of an interpreter at the command line.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Topological_sort | Topological 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
... | #Pascal | Pascal | sub print_topo_sort {
my %deps = @_;
my %ba;
while ( my ( $before, $afters_aref ) = each %deps ) {
for my $after ( @{ $afters_aref } ) {
$ba{$before}{$after} = 1 if $before ne $after;
$ba{$after} ||= {};
}
}
while ( my @afters = sort grep { ! %{ $ba{$_} } ... | Give a code snippet in #Pascal
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/Get_system_command_output | Get system command output | Task
Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.).
Related task
Execute a system command
| #Jsish | Jsish | var commandOutput = exec('ls -gocart', { retAll:true });
puts(commandOutput.data); | Give a code snippet in #Jsish
Task
Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.).
Related task
Execute a system command
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Search_a_list | Search a list | Task[edit]
Find the index of a string (needle) in an indexable, ordered collection of strings (haystack).
Raise an exception if the needle is missing.
If there is more than one occurrence then return the smallest index to the needle.
Extra credit
Return the largest index to a needle that has multiple occurrences in ... | #AWK | AWK | #! /usr/bin/awk -f
BEGIN {
# create the array, using the word as index...
words="Zig Zag Wally Ronald Bush Krusty Charlie Bush Bozo";
split(words, haystack_byorder, " ");
j=0;
for(idx in haystack_byorder) {
haystack[haystack_byorder[idx]] = j;
j++;
}
# now check for needle (we know it is t... | Give a code snippet in #AWK
Task[edit]
Find the index of a string (needle) in an indexable, ordered collection of strings (haystack).
Raise an exception if the needle is missing.
If there is more than one occurrence then return the smallest index to the needle.
Extra credit
Return the largest index to a needle that... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Add_a_variable_to_a_class_instance_at_runtime | Add a variable to a class instance at runtime | Demonstrate how to dynamically add variables to an object (a class instance) at runtime.
This is useful when the methods/variables of an instance are based on a data file that isn't available until runtime. Hal Fulton gives an example of creating an OO CSV parser at An Exercise in Metaprogramming with Ruby. This is re... | #ooRexx | ooRexx |
d = .dynamicvar~new
d~foo = 123
say d~foo
d2 = .dynamicvar2~new
d~bar = "Fred"
say d~bar
-- a class that allows dynamic variables. Since this is a mixin, this
-- capability can be added to any class using multiple inheritance
::class dynamicvar MIXINCLASS object
::method init
expose variables
variables = .di... | Give a code snippet in #ooRexx
Demonstrate how to dynamically add variables to an object (a class instance) at runtime.
This is useful when the methods/variables of an instance are based on a data file that isn't available until runtime. Hal Fulton gives an example of creating an OO CSV parser at An Exercise in Metap... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ramanujan_primes/twins | Ramanujan primes/twins | In a manner similar to twin primes, twin Ramanujan primes may be explored. The task is to determine how many of the first million Ramanujan primes are twins.
Related Task
Twin primes | #Perl | Perl | use strict;
use warnings;
use ntheory <ramanujan_primes nth_ramanujan_prime>;
sub comma { reverse ((reverse shift) =~ s/(.{3})/$1,/gr) =~ s/^,//r }
my $rp = ramanujan_primes nth_ramanujan_prime 1_000_000;
for my $limit (1e5, 1e6) {
printf "The %sth Ramanujan prime is %s\n", comma($limit), comma $rp->[$limit-1];... | Give a code snippet in #Perl
In a manner similar to twin primes, twin Ramanujan primes may be explored. The task is to determine how many of the first million Ramanujan primes are twins.
Related Task
Twin primes | christopher/rosetta-code | |
http://rosettacode.org/wiki/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
... | #AutoHotkey | AutoHotkey | Loop, 100
{
If (Mod(A_Index, 15) = 0)
output .= "FizzBuzz`n"
Else If (Mod(A_Index, 3) = 0)
output .= "Fizz`n"
Else If (Mod(A_Index, 5) = 0)
output .= "Buzz`n"
Else
output .= A_Index "`n"
}
FileDelete, output.txt
FileAppend, %output%, output.txt
Run, cmd /k type output.txt | Give a code snippet in #AutoHotkey
Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print Fiz... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Polymorphism | Polymorphism | Task
Create two classes Point(x,y) and Circle(x,y,r) with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
| #Lua | Lua | -- Point
local Point = {x = 0, y = 0}
function Point:new(o)
o = o or {}
setmetatable(o, self)
self.__index = self
return o
end
function Point:print()
print("Point(" .. self.x .. ", " .. self.y .. ")")
end
function Point:copy()
return Point:new{x = self.x, y = self.y}
end
-- Circle
local ... | Give a code snippet in #Lua
Task
Create two classes Point(x,y) and Circle(x,y,r) with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #GAP | GAP | f:=function ( )
Print( "f:=", f, ";;\nf();\n" );
return;
end;;
f();
| Give a code snippet in #GAP
A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Probabilistic_choice | Probabilistic choice | Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because floating point arithmetic is invol... | #ERRE | ERRE | PROGRAM PROB_CHOICE
DIM ITEM$[7],PROB[7],CNT[7]
BEGIN
ITEM$[]=("aleph","beth","gimel","daleth","he","waw","zayin","heth")
PROB[0]=1/5.0 PROB[1]=1/6.0 PROB[2]=1/7.0 PROB[3]=1/8.0
PROB[4]=1/9.0 PROB[5]=1/10.0 PROB[6]=1/11.0 PROB[7]=1759/27720
SUM=0
FOR I%=0 TO UBOUND(PROB,1) DO
SUM=SUM... | Give a code snippet in #ERRE
Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because floa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/History_variables | History variables | Storing the history of objects in a program is a common task.
Maintaining the history of an object in a program has traditionally required programmers either to write specific code for handling the historical data, or to use a library which supports history logging.
History variables are variables in a programming la... | #Quackery | Quackery | /O> [ stack ] is x
... 3 x put
... 4 x put
... 5 x put
... x behead drop echo cr
... x take echo cr
... x take echo cr
... x take echo cr
...
[ 3 4 5 ]
5
4
3
| Give a code snippet in #Quackery
Storing the history of objects in a program is a common task.
Maintaining the history of an object in a program has traditionally required programmers either to write specific code for handling the historical data, or to use a library which supports history logging.
History variables... | christopher/rosetta-code | |
http://rosettacode.org/wiki/ABC_problem | ABC problem | ABC problem
You are encouraged to solve this task according to the task description, using any language you may know.
You are given a collection of ABC blocks (maybe like the ones you had when you were a kid).
There are twenty blocks with two letters on each block.
A complete alphabet is guaranteed amongst all sid... | #Astro | Astro | fun abc(s, ls):
if ls.isempty:
return true
for i in indices(list) where s[end] in list[i]:
return abc(s[:end-1], remove!(copy(list), at: i))
false
let test = ["A", "BARK","BOOK","TREAT","COMMON","SQUAD","CONFUSE"]
let ls = ["BO","XK","DQ","CP","NA","GT","RE","TG","QD","FS", "JW","HU","VI",... | Give a code snippet in #Astro
ABC problem
You are encouraged to solve this task according to the task description, using any language you may know.
You are given a collection of ABC blocks (maybe like the ones you had when you were a kid).
There are twenty blocks with two letters on each block.
A complete alphabe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Insertion_sort | Sorting algorithms/Insertion 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
... | #AutoHotkey | AutoHotkey | MsgBox % InsertionSort("")
MsgBox % InsertionSort("xxx")
MsgBox % InsertionSort("3,2,1")
MsgBox % InsertionSort("dog,000000,xx,cat,pile,abcde,1,cat,zz,xx,z")
InsertionSort(var) { ; SORT COMMA SEPARATED LIST
StringSplit a, var, `, ; make array, size = a0
Loop % a0-1 {
i :... | Give a code snippet in #AutoHotkey
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Qui... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Echo_server | Echo server | Create a network service that sits on TCP port 12321, which accepts connections on that port, and which echoes complete lines (using a carriage-return/line-feed sequence as line separator) back to clients. No error handling is required. For the purposes of testing, it is only necessary to support connections from local... | #Kotlin | Kotlin | import java.net.ServerSocket
import java.net.Socket
fun main() {
fun handleClient(conn: Socket) {
conn.use {
val input = conn.inputStream.bufferedReader()
val output = conn.outputStream.bufferedWriter()
input.forEachLine { line ->
output.write(line)
... | Give a code snippet in #Kotlin
Create a network service that sits on TCP port 12321, which accepts connections on that port, and which echoes complete lines (using a carriage-return/line-feed sequence as line separator) back to clients. No error handling is required. For the purposes of testing, it is only necessary t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Aime | Aime | Give a code snippet in #Aime
Task
Create the simplest possible program that is still considered "correct."
| christopher/rosetta-code | ||
http://rosettacode.org/wiki/Increment_a_numerical_string | Increment a numerical string | Task
Increment a numerical string.
| #Component_Pascal | Component Pascal |
MODULE Operations;
IMPORT StdLog,Args,Strings;
PROCEDURE IncString(s: ARRAY OF CHAR): LONGINT;
VAR
resp: LONGINT;
done: INTEGER;
BEGIN
Strings.StringToLInt(s,resp,done);
INC(resp);
RETURN resp
END IncString;
PROCEDURE DoIncString*;
VAR
p: Args.Params;
BEGIN
Args.Get(p);
IF p.argc > 0 THEN
StdLog.String(... | Give a code snippet in #Component_Pascal
Task
Increment a numerical string.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Simple_windowed_application | Simple windowed application | Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| #Gastona | Gastona | #javaj#
<frames> main, Simple click counter
<layout of main>
PANEL, X
bClick me, lClicks
#data#
<NN> 0
<lClicks> //There have been no clicks yet
#listix#
<-- bClick me>
NUM=, NN, NN+1
-->, lClicks data!,, //@<NN> clicks so far
| Give a code snippet in #Gastona
Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| 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... | #Phix | Phix | for i=2 to 8 by 2 do
printf(1,"%d, ",i)
end for
printf(1,"who do we appreciate?\n")
| Give a code snippet in #Phix
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/Incr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_largest_left_truncatable_prime_in_a_given_base | Find largest left truncatable prime in a given base | A truncatable prime is one where all non-empty substrings that finish at the end of the number (right-substrings) are also primes when understood as numbers in a particular base. The largest such prime in a given (integer) base is therefore computable, provided the base is larger than 2.
Let's consider what happens in... | #zkl | zkl | var [const] BN=Import("zklBigNum"); // libGMP
fcn largest_lefty_prime(base){
primes,p:=List(),BN(1); while(p.nextPrime()<base){ primes.append(p.copy()) }
b,biggest := BN(1),0;
while(primes){
b*=base; // base,base^2,base^3... gets big
ps:=List();
foreach p,n in (primes,[1..base-1]){
... | Give a code snippet in #zkl
A truncatable prime is one where all non-empty substrings that finish at the end of the number (right-substrings) are also primes when understood as numbers in a particular base. The largest such prime in a given (integer) base is therefore computable, provided the base is larger than 2.
L... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Boolean_values | Boolean values | Task
Show how to represent the boolean states "true" and "false" in a language.
If other objects represent "true" or "false" in conditionals, note it.
Related tasks
Logical operations
| #E | E | ? if (true) { "a" } else { "b" }
# value: "a"
? if (false) { "a" } else { "b" }
# value: "b"
? if (90) { "a" } else { "b" }
# problem: the int 90 doesn't coerce to a boolean | Give a code snippet in #E
Task
Show how to represent the boolean states "true" and "false" in a language.
If other objects represent "true" or "false" in conditionals, note it.
Related tasks
Logical operations
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Rosetta_Code/Find_unimplemented_tasks | Rosetta Code/Find unimplemented tasks | Task
Given the name of a language on Rosetta Code, find all tasks which are not implemented in that language.
Note: Implementations should allow for fetching more data than can be returned in one request to Rosetta Code.
You'll need to use the Media Wiki API, which you can find out about locally, here, or in Media... | #Racket | Racket |
#lang racket
(require net/url net/uri-codec json (only-in racket/dict [dict-ref ref]))
(define (RC-get verb params)
((compose1 get-pure-port string->url format)
"http://rosettacode.org/mw/~a.php?~a" verb (alist->form-urlencoded params)))
(define (get-category catname)
(let loop ([c #f])
(define t
... | Give a code snippet in #Racket
Task
Given the name of a language on Rosetta Code, find all tasks which are not implemented in that language.
Note: Implementations should allow for fetching more data than can be returned in one request to Rosetta Code.
You'll need to use the Media Wiki API, which you can find out ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mayan_calendar | Mayan calendar | The ancient Maya people had two somewhat distinct calendar systems.
In somewhat simplified terms, one is a cyclical calendar known as The Calendar Round,
that meshes several sacred and civil cycles; the other is an offset calendar
known as The Long Count, similar in many ways to the Gregorian calendar.
The Calendar R... | #Fortran | Fortran |
PROGRAM MAYA_DRIVER
IMPLICIT NONE
!
! Local variables
!
CHARACTER(80) :: haab_carry
CHARACTER(80) :: long_carry
CHARACTER(80) :: nightlord
CHARACTER(80) :: tzolkin_carry
INTEGER,DIMENSION(8) :: DAY, MONTH, YEAR
INTEGER :: INDEX
DATA YEAR /2071,2004,2012,20... | Give a code snippet in #Fortran
The ancient Maya people had two somewhat distinct calendar systems.
In somewhat simplified terms, one is a cyclical calendar known as The Calendar Round,
that meshes several sacred and civil cycles; the other is an offset calendar
known as The Long Count, similar in many ways to the Gr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #Never | Never |
func isOdd(n : int) -> int {
n % 2 == 1
}
func isEven(n : int) -> int {
n % 2 == 0
}
| Give a code snippet in #Never
Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pernicious_numbers | Pernicious numbers | A pernicious number is a positive integer whose population count is a prime.
The population count is the number of ones in the binary representation of a non-negative integer.
Example
22 (which is 10110 in binary) has a population count of 3, which is prime, and therefore
22 is a pe... | #Wren | Wren | var pernicious = Fn.new { |w|
var ff = 2.pow(32) - 1
var mask1 = (ff / 3).floor
var mask3 = (ff / 5).floor
var maskf = (ff / 17).floor
var maskp = (ff / 255).floor
w = w - (w >> 1 & mask1)
w = (w & mask3) + (w >>2 & mask3)
w = (w + (w >> 4)) & maskf
return 0xa08a28ac >> (w*maskp >... | Give a code snippet in #Wren
A pernicious number is a positive integer whose population count is a prime.
The population count is the number of ones in the binary representation of a non-negative integer.
Example
22 (which is 10110 in binary) has a population count of 3, which is prime,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_and_product_of_an_array | Sum and product of an array | Task
Compute the sum and product of an array of integers.
| #QBasic | QBasic | DIM array(1 TO 5)
DATA 1, 2, 3, 4, 5
FOR index = LBOUND(array) TO UBOUND(array)
READ array(index)
NEXT index
LET sum = 0
LET prod = 1
FOR index = LBOUND(array) TO UBOUND(array)
LET sum = sum + array(index)
LET prod = prod * array(index)
NEXT index
PRINT "The sum is "; sum
PRINT "and the product is "; prod... | Give a code snippet in #QBasic
Task
Compute the sum and product of an array of integers.
| 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... | #Euphoria | Euphoria | constant data = {
"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$c... | Give a code snippet in #Euphoria
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Heapsort | Sorting algorithms/Heapsort |
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
... | #360_Assembly | 360 Assembly | * Heap sort 22/06/2016
HEAPS CSECT
USING HEAPS,R13 base register
B 72(R15) skip savearea
DC 17F'0' savearea
STM R14,R12,12(R13) prolog
ST R13,4(R15) "
ST ... | Give a code snippet in #360_Assembly
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Q... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence_of_non-squares | Sequence of non-squares | Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A000037 in the OEIS database.
| #Smalltalk | Smalltalk | | nonSquare isSquare squaresFound |
nonSquare := [:n |
n + (n sqrt) rounded
].
isSquare := [:n |
n = (((n sqrt) asInteger) raisedTo: 2)
].
Transcript show: 'The first few non-squares:'; cr.
1 to: 22 do: [:n |
Transcript show: (nonSquare value: n) asString; cr
].
squaresFound := 0.
1 to: 1000000 do: [:n |
... | Give a code snippet in #Smalltalk
Task
Show that the following remarkable formula gives the sequence of non-square natural numbers:
n + floor(1/2 + sqrt(n))
Print out the values for n in the range 1 to 22
Show that no squares occur for n less than one million
This is sequence A0... | 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
... | #Lambdatalk | Lambdatalk |
{require lib_matrix}
{M.determinant
{M.new [[1,2,3],
[4,5,6],
[7,8,9]]}}
-> 0
{M.permanent
{M.new [[1,2,3],
[4,5,6],
[7,8,9]]}}
-> 450
{M.determinant
{M.new [[1,2,3],
[4,5,6],
[7,8,-9]]}}
-> 54
{M.permanent
{M.new [[1,2,3],
[4,5,6],
[7,8,... | Give a code snippet in #Lambdatalk
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}}}
wh... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_length | Array length | Task
Determine the amount of elements in an array.
As an example use an array holding the strings 'apple' and 'orange'.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I befo... | #zonnon | zonnon |
module AryLength;
type
Vector = array 12 of string;
Matrix = array *,* of string;
var
a: Vector;
b: Matrix;
begin
writeln(len(a):4); (* len(a) = len(a,0) *)
b := new Matrix(10,11);
writeln(len(b,0):4); (* first dimension *)
writeln(len(b,1):4) (* second dimension *)
end AryLength.
| Give a code snippet in #zonnon
Task
Determine the amount of elements in an array.
As an example use an array holding the strings 'apple' and 'orange'.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter freq... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_whitespace_from_a_string/Top_and_tail | Strip whitespace from a string/Top and tail | Task
Demonstrate how to strip leading and trailing whitespace from a string.
The solution should demonstrate how to achieve the following three results:
String with leading whitespace removed
String with trailing whitespace removed
String with both leading and trailing whitespace removed
For the purposes of thi... | #C | C | #include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
char *rtrim(const char *s)
{
while( isspace(*s) || !isprint(*s) ) ++s;
return strdup(s);
}
char *ltrim(const char *s)
{
char *r = strdup(s);
if (r != NULL)
{
char *fr = r + strlen(s) - 1;
while( (isspace(*fr) || !isprint... | Give a code snippet in #C
Task
Demonstrate how to strip leading and trailing whitespace from a string.
The solution should demonstrate how to achieve the following three results:
String with leading whitespace removed
String with trailing whitespace removed
String with both leading and trailing whitespace remove... | 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... | #Common_Lisp | Common Lisp | (defun curry (function &rest args-1)
(lambda (&rest args-2)
(apply function (append args-1 args-2))))
| Give a code snippet in #Common_Lisp
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... | 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.
| #AntLang | AntLang | max|range[10] | Give a code snippet in #AntLang
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/Averages/Simple_moving_average | Averages/Simple moving average | Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving average is a method for computing an avera... | #C.23 | C# | using System;
using System.Collections.Generic;
using System.Linq;
namespace SMA {
class Program {
static void Main(string[] args) {
var nums = Enumerable.Range(1, 5).Select(n => (double)n);
nums = nums.Concat(nums.Reverse());
var sma3 = SMA(3);
var sma5 =... | Give a code snippet in #C.23
Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving average is a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #jq | jq | jq -M --raw-input --raw-output '. as $line | $line' input.txt > output.txt
| Give a code snippet in #jq
File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Generic_swap | Generic swap | Task
Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types.
If your solution language is statically typed please describe the way your language provides genericity.
If variables are typed in t... | #PowerShell | PowerShell | $b, $a = $a, $b | Give a code snippet in #PowerShell
Task
Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types.
If your solution language is statically typed please describe the way your language provides gene... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Identity_matrix | Identity matrix | Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
0
1
⋯
0
⋮
⋮
⋮
⋱
... | #Arturo | Arturo | identityM: function [n][
result: array.of: @[n n] 0
loop 0..dec n 'i -> result\[i]\[i]: 1
return result
]
loop 4..6 'sz [
print sz
loop identityM sz => print
print ""
] | Give a code snippet in #Arturo
Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #C | C | #include <stdio.h>
#include <stdlib.h>
int main(void)
{
// Get a string from stdin
char str[BUFSIZ];
puts("Enter a string: ");
fgets(str, sizeof(str), stdin);
// Get 75000 from stdin
long num;
char buf[BUFSIZ];
do
{
puts("Enter 75000: ");
fgets(buf, sizeof(buf), s... | Give a code snippet in #C
User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_definition | Function definition | A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract from showing how functions are ... | #Brat | Brat | multiply = { x, y | x * y }
p multiply 3 14 #Prints 42 | Give a code snippet in #Brat
A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mutual_recursion | Mutual recursion | Two functions are said to be mutually recursive if the first calls the second,
and in turn the second calls the first.
Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as:
F
(
0
)
=
1
;
M
(
0
)
=
0
F
(
n
)
=
n
−
M
(
F
(
n
−
1
)
)
,
... | #Phix | Phix | with javascript_semantics
forward function M(integer n)
function F(integer n)
return iff(n?n-M(F(n-1)):1)
end function
function M(integer n)
return iff(n?n-F(M(n-1)):0)
end function
for i=0 to 20 do
printf(1," %d",F(i))
end for
printf(1,"\n")
for i=0 to 20 do
printf(1," %d",M(i))
end for
| Give a code snippet in #Phix
Two functions are said to be mutually recursive if the first calls the second,
and in turn the second calls the first.
Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as:
F
(
0
)
=
1
;
M
(
0
)
=
0
F
(
n
)... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Formal_power_series | Formal power series | A power series is an infinite sum of the form
a
0
+
a
1
⋅
x
+
a
2
⋅
x
2
+
a
3
⋅
x
3
+
⋯
{\displaystyle a_{0}+a_{1}\cdot x+a_{2}\cdot x^{2}+a_{3}\cdot x^{3}+\cdots }
The ai are called the coefficients of the series. Such sums can be added, multiplied etc., where the new coefficients of ... | #Maxima | Maxima | deftaylor(f(x), sum(n! * x^n, n, 0, inf))$
taylor(f(x), x, 0, 10);
/ * 1 + x + 2 * x^2 + 6 * x^3 + 24 * x^4 + 120 * x^5 + 720 * x^6 + 5040 * x^7 + 40320 * x^8 + 362880 * x^9 + 3628800 * x^10 + ... * /
taylor(f(x)^2, x, 0, 10);
/ * 1 + 2 * x + 5 * x^2 + 16 * x^3 + 64 * x^4 + 312 * x^5 + 1812 * x^6 + 12288 * x^7 + 95... | Give a code snippet in #Maxima
A power series is an infinite sum of the form
a
0
+
a
1
⋅
x
+
a
2
⋅
x
2
+
a
3
⋅
x
3
+
⋯
{\displaystyle a_{0}+a_{1}\cdot x+a_{2}\cdot x^{2}+a_{3}\cdot x^{3}+\cdots }
The ai are called the coefficients of the series. Such sums can be added, multiplied etc.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/One_of_n_lines_in_a_file | One of n lines in a file | A method of choosing a line randomly from a file:
Without reading the file more than once
When substantial parts of the file cannot be held in memory
Without knowing how many lines are in the file
Is to:
keep the first line of the file as a possible choice, then
Read the second line of the file if possible and m... | #F.23 | F# | open System
[<EntryPoint>]
let main args =
let rnd = new Random()
let one_of_n n =
let rec loop i r =
if i >= n then r else
if rnd.Next(i + 1) = 0
then loop (i + 1) i
else loop (i + 1) r
loop 1 0
let test n trials =
le... | Give a code snippet in #F.23
A method of choosing a line randomly from a file:
Without reading the file more than once
When substantial parts of the file cannot be held in memory
Without knowing how many lines are in the file
Is to:
keep the first line of the file as a possible choice, then
Read the second line... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hickerson_series_of_almost_integers | Hickerson series of almost integers | The following function, due to D. Hickerson, is said to generate "Almost integers" by the
"Almost Integer" page of Wolfram MathWorld, (December 31 2013). (See formula numbered 51.)
The function is:
h
(
n
)
=
n
!
2
(
ln
2
)
n
+
1
{\displaystyle h(n)={\operatorname {n} ! \ove... | #Nim | Nim | import strformat
import bignum
let ln2 = newInt("693147180559945309417232121458") / newInt("1000000000000000000000000000000")
iterator hickerson(): tuple[n: int; val: Rat] =
## Yield the hickerson series values as rational numbers.
var
n = 1
num = 1
denom = 2 * ln2 * ln2
while true:
yield (n, ... | Give a code snippet in #Nim
The following function, due to D. Hickerson, is said to generate "Almost integers" by the
"Almost Integer" page of Wolfram MathWorld, (December 31 2013). (See formula numbered 51.)
The function is:
h
(
n
)
=
n
!
2
(
ln
2
)
n
+
1
{\displaystyle h... | 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... | #Rust | Rust | #![feature(core)]
fn sumsqd(mut n: i32) -> i32 {
let mut sq = 0;
while n > 0 {
let d = n % 10;
sq += d*d;
n /= 10
}
sq
}
use std::num::Int;
fn cycle<T: Int>(a: T, f: fn(T) -> T) -> T {
let mut t = a;
let mut h = f(a);
while t != h {
t = f(t);
h =... | Give a code snippet in #Rust
From Wikipedia, the free encyclopedia:
A happy number is defined by the following process:
Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
Cop... | #ColdFusion | ColdFusion | <cfset TestValue=34>
TestValue: <cfoutput>#TestValue#</cfoutput><br>
<cfif isNumeric(TestValue)>
is Numeric.
<cfelse>
is NOT Numeric.
</cfif>
<cfset TestValue="NAS">
TestValue: <cfoutput>#TestValue#</cfoutput><br>
<cfif isNumeric(TestValue)>
is Numeric.
<cfelse>
is NOT Numeric.
</cfif> | Give a code snippet in #ColdFusion
Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metri... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Longest_common_substring | Longest common substring | Task
Write a function that returns the longest common substring of two strings.
Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing".
Note that substrings are consecutive characters within a string.... | #Go | Go | package main
import "fmt"
func lcs(a, b string) (output string) {
lengths := make([]int, len(a)*len(b))
greatestLength := 0
for i, x := range a {
for j, y := range b {
if x == y {
if i == 0 || j == 0 {
lengths[i*len(b)+j] = 1
} else... | Give a code snippet in #Go
Task
Write a function that returns the longest common substring of two strings.
Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing".
Note that substrings are consecutive... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Extreme_floating_point_values | Extreme floating point values | The IEEE floating point specification defines certain 'extreme' floating point values such as minus zero, -0.0, a value distinct from plus zero; not a number, NaN; and plus and minus infinity.
The task is to use expressions involving other 'normal' floating point values in your language to calculate these, (and maybe ... | #Wren | Wren | var inf = 1/0
var negInf = -1/0
var nan = 0/0
var negZero = -0
System.print([inf, negInf, nan, negZero])
System.print([inf + inf, negInf + inf, nan * nan, negZero == 0])
System.print([inf/inf, negInf/2, nan + inf, negZero/0])
| Give a code snippet in #Wren
The IEEE floating point specification defines certain 'extreme' floating point values such as minus zero, -0.0, a value distinct from plus zero; not a number, NaN; and plus and minus infinity.
The task is to use expressions involving other 'normal' floating point values in your language t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Call_a_function_in_a_shared_library | Call a function in a shared library | Show how to call a function in a shared library (without dynamically linking to it at compile-time). In particular, show how to call the shared library function if the library is available, otherwise use an internal equivalent function.
This is a special case of calling a foreign language function where the focus is c... | #COBOL | COBOL | identification division.
program-id. callsym.
data division.
working-storage section.
01 handle usage pointer.
01 addr usage program-pointer.
procedure division.
call "dlopen" using
by reference null
by value 1
returning hand... | Give a code snippet in #COBOL
Show how to call a function in a shared library (without dynamically linking to it at compile-time). In particular, show how to call the shared library function if the library is available, otherwise use an internal equivalent function.
This is a special case of calling a foreign languag... | 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... | #langur | langur | val .select = f(.entries) {
if not isArray(.entries): throw "invalid args"
if len(.entries) == 0: return ZLS
# print the menu
writeln join "\n", map(f $"\.i:2;: \.e;", .entries, 1..len .entries)
val .idx = toNumber read(
"Select entry #: ",
f(.x) {
if not matching(RE/... | Give a code snippet in #langur
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 str... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Digital_root/Multiplicative_digital_root | Digital root/Multiplicative digital root | The multiplicative digital root (MDR) and multiplicative persistence (MP) of a number,
n
{\displaystyle n}
, is calculated rather like the Digital root except digits are multiplied instead of being added:
Set
m
{\displaystyle m}
to
n
{\displaystyle n}
and
i
{\displaystyle i}
to
0
... | #Factor | Factor | USING: arrays formatting fry io kernel lists lists.lazy math
math.text.utils prettyprint sequences ;
IN: rosetta-code.multiplicative-digital-root
: mdr ( n -- {persistence,root} )
0 swap
[ 1 digit-groups dup length 1 > ] [ product [ 1 + ] dip ] while
dup empty? [ drop { 0 } ] when first 2array ;
: print... | Give a code snippet in #Factor
The multiplicative digital root (MDR) and multiplicative persistence (MP) of a number,
n
{\displaystyle n}
, is calculated rather like the Digital root except digits are multiplied instead of being added:
Set
m
{\displaystyle m}
to
n
{\displaystyle n}
and
i
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | mystring = InputString["give me a string please"];
myinteger = Input["give me an integer please"]; | Give a code snippet in #Mathematica_.2F_Wolfram_Language
User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Abundant_odd_numbers | Abundant odd numbers | An Abundant number is a number n for which the sum of divisors σ(n) > 2n,
or, equivalently, the sum of proper divisors (or aliquot sum) s(n) > n.
E.G.
12 is abundant, it has the proper divisors 1,2,3,4 & 6 which sum to 16 ( > 12 or n);
or alternately, has the sigma sum of ... | #REXX | REXX | /*REXX pgm displays abundant odd numbers: 1st 25, one─thousandth, first > 1 billion. */
parse arg Nlow Nuno Novr . /*obtain optional arguments from the CL*/
if Nlow=='' | Nlow=="," then Nlow= 25 /*Not specified? Then use the default.*/
if Nuno=='' | Nuno=="," then Nuno= 1000... | Give a code snippet in #REXX
An Abundant number is a number n for which the sum of divisors σ(n) > 2n,
or, equivalently, the sum of proper divisors (or aliquot sum) s(n) > n.
E.G.
12 is abundant, it has the proper divisors 1,2,3,4 & 6 which sum to 16 ( > 12 or n);
or altern... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Substring | Substring |
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 |... | #Niue | Niue | ( based on the JavaScript code )
'abcdefgh 's ;
s str-len 'len ;
2 'n ;
3 'm ;
( starting from n characters in and of m length )
s n n m + substring . ( => cde ) newline
( starting from n characters in, up to the end of the string )
s n len substring . ( => cdefgh ) newline
( whole string minus last character )
s... | Give a code snippet in #Niue
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #Wrapl | Wrapl | DEF fac(n) n <= 1 | PROD 1:to(n); | Give a code snippet in #Wrapl
Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Exponentiation_order | Exponentiation order | This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show the result of a language's eval... | #min | min | 5 3 2 pow pow
"5 3 2 ^ ^ " print! puts!
5 3 pow 2 pow
"5 3 ^ 2 ^ " print! puts! | Give a code snippet in #min
This task will demonstrate the order of exponentiation (xy) when there are multiple exponents.
(Many programming languages, especially those with extended─precision integer arithmetic, usually support one of **, ^, ↑ or some such for exponentiation.)
Task requirements
Show th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knapsack_problem/Unbounded | Knapsack problem/Unbounded | A traveler gets diverted and has to make an unscheduled stop in what turns out to be Shangri La. Opting to leave, he is allowed to take as much as he likes of the following items, so long as it will fit in his knapsack, and he can carry it.
He knows that he can carry no more than 25 'weights' in total; and tha... | #Go | Go | package main
import "fmt"
type Item struct {
Name string
Value int
Weight, Volume float64
}
type Result struct {
Counts []int
Sum int
}
func min(a, b int) int {
if a < b {
return a
}
return b
}
func Knapsack(items []Item, weight, volume float64) (best Result) {
if len(items) =... | Give a code snippet in #Go
A traveler gets diverted and has to make an unscheduled stop in what turns out to be Shangri La. Opting to leave, he is allowed to take as much as he likes of the following items, so long as it will fit in his knapsack, and he can carry it.
He knows that he can carry no more than 25 '... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roots_of_unity | Roots of unity | The purpose of this task is to explore working with complex numbers.
Task
Given n, find the nth roots of unity.
| #VBA | VBA | Public Sub roots_of_unity()
For n = 2 To 9
Debug.Print n; "th roots of 1:"
For r00t = 0 To n - 1
Debug.Print " Root "; r00t & ": "; WorksheetFunction.Complex(Cos(2 * WorksheetFunction.Pi() * r00t / n), _
Sin(2 * WorksheetFunction.Pi() * r00t / n))
Next r00t
... | Give a code snippet in #VBA
The purpose of this task is to explore working with complex numbers.
Task
Given n, find the nth roots of unity.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Stack_traces | Stack traces | Many programming languages allow for introspection of the current call stack environment. This can be for a variety of purposes such as enforcing security checks, debugging, or for getting access to the stack frame of callers.
Task
Print out (in a manner considered suitable for the platform) the current call stack.... | #DWScript | DWScript | procedure Inner;
begin
try
raise Exception.Create('');
except
on E: Exception do
PrintLn(E.StackTrace);
end;
end;
procedure Middle;
begin
Inner;
end;
procedure Outer;
begin
Middle;
end;
Outer; | Give a code snippet in #DWScript
Many programming languages allow for introspection of the current call stack environment. This can be for a variety of purposes such as enforcing security checks, debugging, or for getting access to the stack frame of callers.
Task
Print out (in a manner considered suitable for the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Perfect_shuffle | Perfect shuffle | A perfect shuffle (or faro/weave shuffle) means splitting a deck of cards into equal halves, and perfectly interleaving them - so that you end up with the first card from the left half, followed by the first card from the right half, and so on:
7♠ 8♠ 9♠ J♠ Q♠ K♠→7♠ 8♠ 9♠
J♠ Q♠ K♠→7♠ J♠ 8♠ Q♠ 9♠ K♠
When you ... | #Factor | Factor | USING: arrays formatting kernel math prettyprint sequences
sequences.merged ;
IN: rosetta-code.perfect-shuffle
CONSTANT: test-cases { 8 24 52 100 1020 1024 10000 }
: shuffle ( seq -- seq' ) halves 2merge ;
: shuffle-count ( n -- m )
<iota> >array 0 swap dup [ 2dup = ] [ shuffle [ 1 + ] 2dip ]
do until 2dr... | Give a code snippet in #Factor
A perfect shuffle (or faro/weave shuffle) means splitting a deck of cards into equal halves, and perfectly interleaving them - so that you end up with the first card from the left half, followed by the first card from the right half, and so on:
7♠ 8♠ 9♠ J♠ Q♠ K♠→7♠ 8♠ 9♠
J♠ Q♠ ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-decimal_radices/Convert | Non-decimal radices/Convert | Number base conversion is when you express a stored integer in an integer base, such as in octal (base 8) or binary (base 2). It also is involved when you take a string representing a number in a given base and convert it to the stored integer form. Normally, a stored integer is in binary, but that's typically invisibl... | #Action.21 | Action! | CHAR ARRAY digits="0123456789abcdefghijklmnopqrstuvwxyz"
PROC CheckBase(BYTE b)
IF b<2 OR b>digits(0) THEN
PrintE("Base is out of range!")
Break()
FI
RETURN
PROC Encode(CARD v BYTE b CHAR ARRAY s)
CARD d
BYTE i,len
CHAR tmp
CheckBase(b)
len=0
DO
d=v MOD b
len==+1
s(len)=digits(... | Give a code snippet in #Action.21
Number base conversion is when you express a stored integer in an integer base, such as in octal (base 8) or binary (base 2). It also is involved when you take a string representing a number in a given base and convert it to the stored integer form. Normally, a stored integer is in bi... | 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.
| #Julia | Julia | A = [1 2 3; 4 1 6; 7 8 9]
@show I / A
@show inv(A) | Give a code snippet in #Julia
Task
Invert matrix A using Gauss-Jordan method.
A being an n × n matrix.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Simple_moving_average | Averages/Simple moving average | Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving average is a method for computing an avera... | #Pascal | Pascal | program sma;
type
tsma = record
smaValue : array of double;
smaAverage,
smaSumOld,
smaSumNew,
smaRezActLength : double;
smaActLength,
smaLength,
smaPos :NativeInt;
smaIsntFull: boolean;
end;
proced... | Give a code snippet in #Pascal
Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving average is... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitwise_IO | Bitwise IO | The aim of this task is to write functions (or create a class if your
language is Object Oriented and you prefer) for reading and writing sequences of
bits, most significant bit first. While the output of a asciiprint "STRING" is the ASCII byte sequence
"S", "T", "R", "I", "N", "G", the output of a "print" of the bits ... | #Phix | Phix | without js -- (file i/o)
enum FN, V, BITS -- fields of a bitwiseioreader/writer
function new_bitwiseio(string filename, mode)
integer fn = open(filename,mode)
return {fn,0,0} -- ie {FN,V=0,BITS=0}
end function
function new_bitwiseiowriter(string filename)
return new_bitwiseio(filename,"wb")
end func... | Give a code snippet in #Phix
The aim of this task is to write functions (or create a class if your
language is Object Oriented and you prefer) for reading and writing sequences of
bits, most significant bit first. While the output of a asciiprint "STRING" is the ASCII byte sequence
"S", "T", "R", "I", "N", "G", the ou... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bulls_and_cows/Player | Bulls and cows/Player | Task
Write a player of the Bulls and Cows game, rather than a scorer. The player should give intermediate answers that respect the scores to previous attempts.
One method is to generate a list of all possible numbers that could be the answer, then to prune the list by keeping only those numbers that would give an equ... | #Phix | Phix | with javascript_semantics
constant line = " +---------+-----------------------------+-------+------+\n",
digits = "123456789"
function mask(integer ch)
return power(2,ch-'1')
end function
function score(string guess, goal)
integer bits = 0, bulls = 0, cows = 0
for i=1 to length(guess) do
... | Give a code snippet in #Phix
Task
Write a player of the Bulls and Cows game, rather than a scorer. The player should give intermediate answers that respect the scores to previous attempts.
One method is to generate a list of all possible numbers that could be the answer, then to prune the list by keeping only those ... | 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... | #Eiffel | Eiffel |
class
APPLICATION
create
make
feature {NONE} -- Initialization
make
local
bottles: INTEGER
do
from
bottles := 99
invariant
bottles <= 99 and bottles >= 1
until
bottles = 1
loop
print (bottles)
print (" bottles of beer on the wall,%N")
print (bottles)
print (" bo... | Give a code snippet in #Eiffel
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
9... | christopher/rosetta-code | |
http://rosettacode.org/wiki/SHA-1 | SHA-1 | SHA-1 or SHA1 is a one-way hash function;
it computes a 160-bit message digest.
SHA-1 often appears in security protocols; for example,
many HTTPS websites use RSA with SHA-1 to secure their connections.
BitTorrent uses SHA-1 to verify downloads.
Git and Mercurial use SHA-1 digests to identify commits.
A US government... | #Genie | Genie | print Checksum.compute_for_string(ChecksumType.SHA1, "Rosetta code", -1) | Give a code snippet in #Genie
SHA-1 or SHA1 is a one-way hash function;
it computes a 160-bit message digest.
SHA-1 often appears in security protocols; for example,
many HTTPS websites use RSA with SHA-1 to secure their connections.
BitTorrent uses SHA-1 to verify downloads.
Git and Mercurial use SHA-1 digests to ide... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Long_year | Long year | Most years have 52 weeks, some have 53, according to ISO8601.
Task
Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
| #Prolog | Prolog | % See https://en.wikipedia.org/wiki/ISO_week_date#Weeks_per_year
p(Year, P):-
P is (Year + (Year//4) - (Year//100) + (Year//400)) mod 7.
long_year(Year):-
p(Year, 4),
!.
long_year(Year):-
Year_before is Year - 1,
p(Year_before, 3).
print_long_years(From, To):-
writef("Long years between %w... | Give a code snippet in #Prolog
Most years have 52 weeks, some have 53, according to ISO8601.
Task
Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Play_recorded_sounds | Play recorded sounds | Load at least two prerecorded sounds, and demonstrate as many of these features as you can:
playing them individually and simultaneously
stopping before the end of the sound
looping (preferably glitch-free)
setting the volume of each sound
stereo or 3D positional mixing
performing other actions when marked times... | #Racket | Racket |
#lang racket/gui
(play-sound "some-sound.wav" #f)
| Give a code snippet in #Racket
Load at least two prerecorded sounds, and demonstrate as many of these features as you can:
playing them individually and simultaneously
stopping before the end of the sound
looping (preferably glitch-free)
setting the volume of each sound
stereo or 3D positional mixing
performing... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Minesweeper_game | Minesweeper game | There is an n by m grid that has a random number (between 10% to 20% of the total number of tiles, though older implementations may use 20%..60% instead) of randomly placed mines that need to be found.
Positions in the grid are modified by entering their coordinates where the first coordinate is horizontal in the grid... | #C | C | #if 0
Unix build:
make CPPFLAGS=-DNDEBUG LDLIBS=-lcurses mines
dwlmines, by David Lambert; sometime in the twentieth Century. The
program is meant to run in a terminal window compatible with curses
if unix is defined to cpp, or to an ANSI terminal when compiled
without unix macro defined. ... | Give a code snippet in #C
There is an n by m grid that has a random number (between 10% to 20% of the total number of tiles, though older implementations may use 20%..60% instead) of randomly placed mines that need to be found.
Positions in the grid are modified by entering their coordinates where the first coordinat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Minesweeper_game | Minesweeper game | There is an n by m grid that has a random number (between 10% to 20% of the total number of tiles, though older implementations may use 20%..60% instead) of randomly placed mines that need to be found.
Positions in the grid are modified by entering their coordinates where the first coordinate is horizontal in the grid... | #PHP | PHP | <?php
define('MINEGRID_WIDTH', 6);
define('MINEGRID_HEIGHT', 4);
define('MINESWEEPER_NOT_EXPLORED', -1);
define('MINESWEEPER_MINE', -2);
define('MINESWEEPER_FLAGGED', -3);
define('MINESWEEPER_FLAGGED_MINE', -4);
define('ACTIVATED_MINE', -5);
function check_field($field) {
if ($field === ... | Give a code snippet in #PHP
There is an n by m grid that has a random number (between 10% to 20% of the total number of tiles, though older implementations may use 20%..60% instead) of randomly placed mines that need to be found.
Positions in the grid are modified by entering their coordinates where the first coordin... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | x=value assign a value to the variable x
x=y=value assign a value to both x and y
x=. or Clear[x] remove any value assigned to x
lhs=rhs (immediate assignment) rhs is evaluated when the assignment is made
lhs:=rhs (delayed assignment) rhs is evaluated each time the value of lhs is requested | Give a code snippet in #Mathematica.2FWolfram_Language
Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap | Bitmap | Show a basic storage type to handle a simple RGB raster graphics image,
and some primitive associated functions.
If possible provide a function to allocate an uninitialised image,
given its width and height, and provide 3 additional functions:
one to fill an image with a plain RGB color,
one to set a given pixe... | #Rust | Rust | #[derive(Copy, Clone, Debug, PartialEq, Eq)]
pub struct Rgb {
pub r: u8,
pub g: u8,
pub b: u8,
}
impl Rgb {
pub fn new(r: u8, g: u8, b: u8) -> Self {
Rgb { r, g, b }
}
pub const BLACK: Rgb = Rgb { r: 0, g: 0, b: 0 };
pub const RED: Rgb = Rgb { r: 255, g: 0, b: 0 };
pub const ... | Give a code snippet in #Rust
Show a basic storage type to handle a simple RGB raster graphics image,
and some primitive associated functions.
If possible provide a function to allocate an uninitialised image,
given its width and height, and provide 3 additional functions:
one to fill an image with a plain RGB col... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stack | Stack |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is accessed through its top.
The ba... | #R | R | library(proto)
stack <- proto(expr = {
l <- list()
empty <- function(.) length(.$l) == 0
push <- function(., x)
{
.$l <- c(list(x), .$l)
print(.$l)
invisible()
}
pop <- function(.)
{
if(.$empty()) stop("can't pop from an empty list")
.$l[[1]] <- NULL
print(.$... | Give a code snippet in #R
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is access... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Insertion_sort | Sorting algorithms/Insertion 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
... | #Ruby | Ruby | class Array
def insertionsort!
1.upto(length - 1) do |i|
value = self[i]
j = i - 1
while j >= 0 and self[j] > value
self[j+1] = self[j]
j -= 1
end
self[j+1] = value
end
self
end
end
ary = [7,6,5,9,8,4,3,1,2,0]
p ary.insertionsort!
# => [0, 1, 2, 3, 4, 5, 6, ... | Give a code snippet in #Ruby
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/CSV_to_HTML_translation | CSV to HTML translation | Consider a simplified CSV format where all rows are separated by a newline
and all columns are separated by commas.
No commas are allowed as field data, but the data may contain
other characters and character sequences that would
normally be escaped when converted to HTML
Task
Create a function that takes a st... | #Nanoquery | Nanoquery | // a method that converts a csv row into a html table row as a string
def toHtmlRow(record, tag)
htmlrow = "\t<tr>\n"
// loop through the values in the current csv row
for i in range(1, len(record))
htmlrow = htmlrow + "\t\t<" + tag + ">" + (record ~ i) + "</" + tag + ">\n"
end for
return htmlrow + "\t</tr>\... | Give a code snippet in #Nanoquery
Consider a simplified CSV format where all rows are separated by a newline
and all columns are separated by commas.
No commas are allowed as field data, but the data may contain
other characters and character sequences that would
normally be escaped when converted to HTML
Task... | 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... | #Objective-C | Objective-C |
@import Foundation;
int main(int argc, const char * argv[]) {
@autoreleasepool {
// Create a mutable array
NSMutableArray *doorArray = [@[] mutableCopy];
// Fill the doorArray with 100 closed doors
for (NSInteger i = 0; i < 100; ++i) {
doorArray[i] = @NO;
... | Give a code snippet in #Objective-C
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, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation | Horner's rule for polynomial evaluation | A fast scheme for evaluating a polynomial such as:
−
19
+
7
x
−
4
x
2
+
6
x
3
{\displaystyle -19+7x-4x^{2}+6x^{3}\,}
when
x
=
3
{\displaystyle x=3\;}
.
is to arrange the computation as follows:
(
(
(
(
0
)
x
+
6
)
x
+
(
−
4
)
)
x
+
7
)
x
+
(
−
19
)
{\displaystyle ((((0)x+6)x+(-4))x... | #C.2B.2B | C++ | #include <iostream>
#include <vector>
using namespace std;
double horner(vector<double> v, double x)
{
double s = 0;
for( vector<double>::const_reverse_iterator i = v.rbegin(); i != v.rend(); i++ )
s = s*x + *i;
return s;
}
int main()
{
double c[] = { -19, 7, -4, 6 };
vector<double> v(c, c + sizeo... | Give a code snippet in #C.2B.2B
A fast scheme for evaluating a polynomial such as:
−
19
+
7
x
−
4
x
2
+
6
x
3
{\displaystyle -19+7x-4x^{2}+6x^{3}\,}
when
x
=
3
{\displaystyle x=3\;}
.
is to arrange the computation as follows:
(
(
(
(
0
)
x
+
6
)
x
+
(
−
4
)
)
x
+
7
)
x
+
(
−
19
)
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Circles_of_given_radius_through_two_points | Circles of given radius through two points |
Given two points on a plane and a radius, usually two circles of given radius can be drawn through the points.
Exceptions
r==0.0 should be treated as never describing circles (except in the case where the points are coincident).
If the points are coincident then an infinite number of circles with the point on thei... | #Raku | Raku | multi sub circles (@A, @B where ([and] @A Z== @B), 0.0) { 'Degenerate point' }
multi sub circles (@A, @B where ([and] @A Z== @B), $) { 'Infinitely many share a point' }
multi sub circles (@A, @B, $radius) {
my @middle = (@A Z+ @B) X/ 2;
my @diff = @A Z- @B;
my $q = sqrt [+] @diff X** 2;
return 'Too fa... | Give a code snippet in #Raku
Given two points on a plane and a radius, usually two circles of given radius can be drawn through the points.
Exceptions
r==0.0 should be treated as never describing circles (except in the case where the points are coincident).
If the points are coincident then an infinite number of ... | christopher/rosetta-code |
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