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 |
|---|---|---|---|---|---|
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of... | #C.23 | C# | public class Program
{
public static void Main()
{
const int count = 5;
const int Baker = 0, Cooper = 1, Fletcher = 2, Miller = 3, Smith = 4;
string[] names = { nameof(Baker), nameof(Cooper), nameof(Fletcher), nameof(Miller), nameof(Smith) };
Func<int[], bool>[] constraints = {... |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #CLU | CLU | % Compute the dot product of two sequences
% If the sequences are not the same length, it signals length_mismatch
% Any type may be used as long as it supports addition and multiplication
dot_product = proc [T: type] (a, b: sequence[T])
returns (T) signals (length_mismatch, empty, overflow)
... |
http://rosettacode.org/wiki/Doubly-linked_list/Definition | Doubly-linked list/Definition | Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | #Oforth | Oforth | Object Class new: DNode(value, mutable prev, mutable next)
DNode method: initialize := next := prev := value ;
DNode method: value @value ;
DNode method: prev @prev ;
DNode method: next @next ;
DNode method: setPrev := prev ;
DNode method: setNext := next ;
DNode method: << @value << ;
DNode method: insertAft... |
http://rosettacode.org/wiki/Dice_game_probabilities | Dice game probabilities | Two players have a set of dice each. The first player has nine dice with four faces each, with numbers one to four. The second player has six normal dice with six faces each, each face has the usual numbers from one to six.
They roll their dice and sum the totals of the faces. The player with the highest total wins (i... | #D | D | import std.stdio, std.range, std.algorithm;
void throwDie(in uint nSides, in uint nDice, in uint s, uint[] counts)
pure nothrow @safe @nogc {
if (nDice == 0) {
counts[s]++;
return;
}
foreach (immutable i; 1 .. nSides + 1)
throwDie(nSides, nDice - 1, s + i, counts);
}
real beati... |
http://rosettacode.org/wiki/Dining_philosophers | Dining philosophers | The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a rou... | #C | C | #include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdarg.h>
#define N 5
const char *names[N] = { "Aristotle", "Kant", "Spinoza", "Marx", "Russell" };
pthread_mutex_t forks[N];
#define M 5 /* think bubbles */
const char *topic[M] = { "Spaghetti!", "Life", "Universe", "Everythi... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #AWK | AWK |
# DDATE.AWK - Gregorian to Discordian date contributed by Dan Nielsen
# syntax: GAWK -f DDATE.AWK [YYYYMMDD | YYYY-MM-DD | MM-DD-YYYY | DDMMMYYYY | YYYY] ...
# examples:
# GAWK -f DDATE.AWK today
# GAWK -f DDATE.AWK 20110722 one date
# GAWK -f DDATE.AWK 20110722 20120229 two dates
... |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path pro... | #AutoHotkey | AutoHotkey | Dijkstra(data, start){
nodes := [], dist := [], Distance := [], dist := [], prev := [], Q := [], min := "x"
for each, line in StrSplit(data, "`n" , "`r")
field := StrSplit(line,"`t"), nodes[field.1] := 1, nodes[field.2] := 1
, Distance[field.1,field.2] := field.3, Distance[field.2,field.1] := field.3
dist[start]... |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displ... | #AutoHotkey | AutoHotkey | p := {}
for key, val in [30,1597,381947,92524902,448944221089]
{
n := val
while n > 9
{
m := 0
Loop, Parse, n
m += A_LoopField
n := m, i := A_Index
}
p[A_Index] := [val, n, i]
}
for key, val in p
Output .= val[1] ": Digital Root = " val[2] ", Additive Persis... |
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
... | #F.23 | F# |
// mdr. Nigel Galloway: June 29th., 2021
let rec fG n g=if n=0 then g else fG(n/10)(g*(n%10))
let mdr n=let rec mdr n g=if n<10 then (n,g) else mdr(fG n 1)(g+1) in mdr n 0
[123321; 7739; 893; 899998] |> List.iter(fun i->let n,g=mdr i in printfn "%d has mdr=%d with persitance %d" i n g)
let fN g=Seq.initInfinite id|>S... |
http://rosettacode.org/wiki/Dragon_curve | Dragon curve |
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by a left dragon, at 90-degree an... | #LaTeX | LaTeX | \documentclass{minimal}
\usepackage{tikz}
\usetikzlibrary{lindenmayersystems}
\pgfdeclarelindenmayersystem{Dragon curve}{
\symbol{S}{\pgflsystemdrawforward}
\rule{F -> -F++S-}
\rule{S -> +F--S+}
}
\foreach \i in {1,...,8} {
\hbox{
order=\i
\hspace{.5em}
\begin{tikzpicture}[baseli... |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of... | #Ceylon | Ceylon | shared void run() {
function notAdjacent(Integer a, Integer b) => (a - b).magnitude >= 2;
function allDifferent(Integer* ints) => ints.distinct.size == ints.size;
value solutions = [
for (baker in 1..4)
for (cooper in 2..5)
for (fletcher in 2..4)
for (miller in 2..5)
for (smith in 1..5)
if (miller > ... |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #CoffeeScript | CoffeeScript | dot_product = (ary1, ary2) ->
if ary1.length != ary2.length
throw "can't find dot product: arrays have different lengths"
dotprod = 0
for v, i in ary1
dotprod += v * ary2[i]
dotprod
console.log dot_product([ 1, 3, -5 ], [ 4, -2, -1 ]) # 3
try
console.log dot_product([ 1, 3, -5 ], [ 4, -2, -1, 0 ]) #... |
http://rosettacode.org/wiki/Doubly-linked_list/Definition | Doubly-linked list/Definition | Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | #Phix | Phix | +------------> start
|
+--+--+-----+
| | | ---+---> end
+-----+-----+
|
http://rosettacode.org/wiki/Dice_game_probabilities | Dice game probabilities | Two players have a set of dice each. The first player has nine dice with four faces each, with numbers one to four. The second player has six normal dice with six faces each, each face has the usual numbers from one to six.
They roll their dice and sum the totals of the faces. The player with the highest total wins (i... | #Factor | Factor | USING: dice generalizations kernel math prettyprint sequences ;
IN: rosetta-code.dice-probabilities
: winning-prob ( a b c d -- p )
[ [ random-roll ] 2bi@ > ] 4 ncurry [ 100000 ] dip replicate
[ [ t = ] count ] [ length ] bi /f ;
9 4 6 6 winning-prob
5 10 6 7 winning-prob [ . ] bi@ |
http://rosettacode.org/wiki/Dice_game_probabilities | Dice game probabilities | Two players have a set of dice each. The first player has nine dice with four faces each, with numbers one to four. The second player has six normal dice with six faces each, each face has the usual numbers from one to six.
They roll their dice and sum the totals of the faces. The player with the highest total wins (i... | #Gambas | Gambas | ' Gambas module file
Public Sub Main()
Dim iSides, iPlayer1, iPlayer2, iTotal1, iTotal2, iCount, iCount0 As Integer
Dim iDice1 As Integer = 9
Dim iDice2 As Integer = 6
Dim iSides1 As Integer = 4
Dim iSides2 As Integer = 6
Randomize
For iCount0 = 0 To 1
For iCount = 1 To 100000
iPlayer1 = Roll(iDice1, iSides... |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #Ada | Ada | with Ada.Text_IO;
procedure Single_Instance is
package IO renames Ada.Text_IO;
Lock_File: IO.File_Type;
Lock_File_Name: String := "single_instance.magic_lock";
begin
begin
IO.Open(File => Lock_File, Mode=> IO.In_File, Name => Lock_File_Name);
IO.Close(Lock_File);
IO.Put_Line("I can't... |
http://rosettacode.org/wiki/Dining_philosophers | Dining philosophers | The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a rou... | #C.23 | C# |
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
namespace Dining_Philosophers
{
class Program
{
private const int DinerCount = 5;
private static List<Diner> Diners = new List<Diner>();
private... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #BASIC | BASIC | #INCLUDE "datetime.bi"
DECLARE FUNCTION julian(AS DOUBLE) AS INTEGER
SeasonNames:
DATA "Chaos", "Discord", "Confusion", "Bureaucracy", "The Aftermath"
Weekdays:
DATA "Setting Orange", "Sweetmorn", "Boomtime", "Pungenday", "Prickle-Prickle"
DaysPreceding1stOfMonth:
' jan feb mar apr may jun jul aug sep oct n... |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path pro... | #C | C | #include <stdio.h>
#include <stdlib.h>
#include <limits.h>
typedef struct {
int vertex;
int weight;
} edge_t;
typedef struct {
edge_t **edges;
int edges_len;
int edges_size;
int dist;
int prev;
int visited;
} vertex_t;
typedef struct {
vertex_t **vertices;
int vertices_len;... |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displ... | #AWK | AWK | # syntax: GAWK -f DIGITAL_ROOT.AWK
BEGIN {
n = split("627615,39390,588225,393900588225,10,199",arr,",")
for (i=1; i<=n; i++) {
dr = digitalroot(arr[i],10)
printf("%12.0f has additive persistence %d and digital root of %d\n",arr[i],p,dr)
}
exit(0)
}
function digitalroot(n,b) {
p = 0 # glo... |
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... |
http://rosettacode.org/wiki/Dragon_curve | Dragon curve |
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by a left dragon, at 90-degree an... | #TI-89_BASIC | TI-89 BASIC | Define dragon = (iter, xform)
Prgm
Local a,b
If iter > 0 Then
dragon(iter-1, xform*[[.5,.5,0][–.5,.5,0][0,0,1]])
dragon(iter-1, xform*[[–.5,.5,0][–.5,–.5,1][0,0,1]])
Else
xform*[0;0;1]→a
xform*[0;1;1]→b
PxlLine floor(a[1,1]), floor(a[2,1]), floor(b[1,1]), floor(b[2,1])
EndIf
EndPrgm
FnOff
... |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of... | #Clojure | Clojure | (ns rosettacode.dinesman
(:use [clojure.core.logic]
[clojure.tools.macro :as macro]))
; whether x is immediately above (left of) y in list s; uses pattern matching on s
(defne aboveo [x y s]
([_ _ (x y . ?rest)])
([_ _ [_ . ?rest]] (aboveo x y ?rest)))
; whether x is on a higher floor than y... |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #Common_Lisp | Common Lisp | (defun dot-product (a b)
(apply #'+ (mapcar #'* (coerce a 'list) (coerce b 'list)))) |
http://rosettacode.org/wiki/Doubly-linked_list/Definition | Doubly-linked list/Definition | Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | #PicoLisp | PicoLisp | +------------> start
|
+--+--+-----+
| | | ---+---> end
+-----+-----+
|
http://rosettacode.org/wiki/Dice_game_probabilities | Dice game probabilities | Two players have a set of dice each. The first player has nine dice with four faces each, with numbers one to four. The second player has six normal dice with six faces each, each face has the usual numbers from one to six.
They roll their dice and sum the totals of the faces. The player with the highest total wins (i... | #Go | Go | package main
import(
"math"
"fmt"
)
func minOf(x, y uint) uint {
if x < y {
return x
}
return y
}
func throwDie(nSides, nDice, s uint, counts []uint) {
if nDice == 0 {
counts[s]++
return
}
for i := uint(1); i <= nSides; i++ {
throwDie(nSides, nDice -... |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #AutoHotkey | AutoHotkey | PRAGMA INCLUDE <sys/file.h>
OPTION DEVICE O_NONBLOCK
OPEN ME$ FOR DEVICE AS me
IF flock(me, LOCK_EX | LOCK_NB) <> 0 THEN
PRINT "I am already running, exiting..."
END
ENDIF
PRINT "Running this program, doing things..."
SLEEP 5000
CLOSE DEVICE me |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #BaCon | BaCon | PRAGMA INCLUDE <sys/file.h>
OPTION DEVICE O_NONBLOCK
OPEN ME$ FOR DEVICE AS me
IF flock(me, LOCK_EX | LOCK_NB) <> 0 THEN
PRINT "I am already running, exiting..."
END
ENDIF
PRINT "Running this program, doing things..."
SLEEP 5000
CLOSE DEVICE me |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #Bash_Shell | Bash Shell |
local fd=${2:-200}
# create lock file
eval "exec $fd>/tmp/my_lock.lock"
# acquire the lock, or fail
flock -nx $fd \
&& # do something if you got the lock \
|| # do something if you did not get the lock
|
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #BBC_BASIC | BBC BASIC | SYS "CreateMutex", 0, 1, "UniqueLockName" TO Mutex%
SYS "GetLastError" TO lerr%
IF lerr% = 183 THEN
SYS "CloseHandle", Mutex%
SYS "MessageBox", @hwnd%, "I am already running", 0, 0
QUIT
ENDIF
SYS "ReleaseMutex", Mutex%
SYS "CloseHandle", Mutex%
END |
http://rosettacode.org/wiki/Dining_philosophers | Dining philosophers | The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a rou... | #C.2B.2B | C++ | #include <algorithm>
#include <array>
#include <chrono>
#include <iostream>
#include <mutex>
#include <random>
#include <string>
#include <string_view>
#include <thread>
const int timeScale = 42; // scale factor for the philosophers task duration
void Message(std::string_view message)
{
// thread safe printing... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #Batch_File | Batch File | @echo off
goto Parse
Discordian Date Converter:
Usage:
ddate
ddate /v
ddate /d isoDate
ddate /v /d isoDate
:Parse
shift
if "%0"=="" goto Prologue
if "%0"=="/v" set Verbose=1
if "%0"=="/d" set dateToTest=%1
if "%0"=="/d" shift
goto Parse
:Prologue
if "%dateToTest%"=="" set dateToTest=%date%
for... |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path pro... | #C.23 | C# | using static System.Linq.Enumerable;
using static System.String;
using static System.Console;
using System.Collections.Generic;
using System;
using EdgeList = System.Collections.Generic.List<(int node, double weight)>;
public static class Dijkstra
{
public static void Main() {
Graph graph = new Graph(6);
... |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displ... | #BASIC | BASIC | DECLARE SUB digitalRoot (what AS LONG)
'test inputs:
digitalRoot 627615
digitalRoot 39390
digitalRoot 588225
SUB digitalRoot (what AS LONG)
DIM w AS LONG, t AS LONG, c AS INTEGER
w = ABS(what)
IF w > 10 THEN
DO
c = c + 1
WHILE w
t = t + (w MOD (10))
... |
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
... | #Fortran | Fortran |
!Implemented by Anant Dixit (Oct, 2014)
program mdr
implicit none
integer :: i, mdr, mp, n, j
character(len=*), parameter :: hfmt = '(A18)', nfmt = '(I6)'
character(len=*), parameter :: cfmt = '(A3)', rfmt = '(I3)', ffmt = '(I9)'
write(*,hfmt) 'Number MDR MP '
write(*,*) '------------------'
i = 123321
call r... |
http://rosettacode.org/wiki/Dragon_curve | Dragon curve |
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by a left dragon, at 90-degree an... | #Vedit_macro_language | Vedit macro language | File_Open("|(USER_MACRO)\dragon.bmp", OVERWRITE+NOEVENT)
BOF Del_Char(ALL)
#11 = 640 // width of the image
#12 = 480 // height of the image
Call("CREATE_BMP")
#1 = 384 // dx
#2 = 0 // dy
#3 = 6 // depth of recursion
#4 = 1 // flip
#5 = 150 // x
#6 = 300 // y
Call("DRAGON")
Buf_Close(NOMSG)
Sys(`start "... |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of... | #Common_Lisp | Common Lisp |
(defpackage :dinesman
(:use :cl
:screamer)
(:export :dinesman :dinesman-list))
(in-package :dinesman)
(defun distinctp (list)
(equal list (remove-duplicates list)))
(defun dinesman ()
(all-values
(let ((baker (an-integer-between 1 5))
(cooper (an-integer-between 1 5))
(flet... |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #Component_Pascal | Component Pascal |
MODULE DotProduct;
IMPORT StdLog;
PROCEDURE Calculate*(x,y: ARRAY OF INTEGER): INTEGER;
VAR
i,sum: INTEGER;
BEGIN
sum := 0;
FOR i:= 0 TO LEN(x) - 1 DO
INC(sum,x[i] * y[i]);
END;
RETURN sum
END Calculate;
PROCEDURE Test*;
VAR
i,sum: INTEGER;
v1,v2: ARRAY 3 OF INTEGER;
BEGIN
v1[0] := 1;v1[1] := 3;v1[2] :=... |
http://rosettacode.org/wiki/Doubly-linked_list/Definition | Doubly-linked list/Definition | Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | #PL.2FI | PL/I |
define structure
1 Node,
2 value fixed decimal,
2 back_pointer handle(Node),
2 fwd_pointer handle(Node);
|
http://rosettacode.org/wiki/Dice_game_probabilities | Dice game probabilities | Two players have a set of dice each. The first player has nine dice with four faces each, with numbers one to four. The second player has six normal dice with six faces each, each face has the usual numbers from one to six.
They roll their dice and sum the totals of the faces. The player with the highest total wins (i... | #Haskell | Haskell | import Control.Monad (replicateM)
import Data.List (group, sort)
succeeds :: (Int, Int) -> (Int, Int) -> Double
succeeds p1 p2 =
sum
[ realToFrac (c1 * c2) / totalOutcomes
| (s1, c1) <- countSums p1
, (s2, c2) <- countSums p2
, s1 > s2 ]
where
totalOutcomes = realToFrac $ uncurry (^) p1 * un... |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #C | C | #include <fcntl.h> /* fcntl, open */
#include <stdlib.h> /* atexit, getenv, malloc */
#include <stdio.h> /* fputs, printf, puts, snprintf */
#include <string.h> /* memcpy */
#include <unistd.h> /* sleep, unlink */
/* Filename for only_one_instance() lock. */
#define INSTANCE_LOCK "rosetta-code-lock"
void
fail(const... |
http://rosettacode.org/wiki/Dining_philosophers | Dining philosophers | The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a rou... | #Clojure | Clojure | (defn make-fork []
(ref true))
(defn make-philosopher [name forks food-amt]
(ref {:name name :forks forks :eating? false :food food-amt}))
(defn start-eating [phil]
(dosync
(if (every? true? (map ensure (:forks @phil))) ; <-- the essential solution
(do
(doseq [f (:forks @phil)] (alter f no... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #BBC_BASIC | BBC BASIC | INSTALL @lib$+"DATELIB"
PRINT "01/01/2011 -> " FNdiscordian("01/01/2011")
PRINT "05/01/2011 -> " FNdiscordian("05/01/2011")
PRINT "28/02/2011 -> " FNdiscordian("28/02/2011")
PRINT "01/03/2011 -> " FNdiscordian("01/03/2011")
PRINT "22/07/2011 -> " FNdiscordian("22/07/2011")
PR... |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path pro... | #C.2B.2B | C++ | #include <iostream>
#include <vector>
#include <string>
#include <list>
#include <limits> // for numeric_limits
#include <set>
#include <utility> // for pair
#include <algorithm>
#include <iterator>
typedef int vertex_t;
typedef double weight_t;
const weight_t max_weight = std::numeric_limits<double>::infinit... |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displ... | #Batch_File | Batch File | :: Digital Root Task from Rosetta Code Wiki
:: Batch File Implementation
:: (Base 10)
@echo off
setlocal enabledelayedexpansion
:: THE MAIN THING
for %%x in (9876543214 393900588225 1985989328582 34559) do call :droot %%x
echo(
pause
exit /b
:: /THE MAIN THING
:: THE FUNCTION
:droot
set inp2sum=%1
set persist=1
:... |
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
... | #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Function multDigitalRoot(n As UInteger, ByRef mp As Integer, base_ As Integer = 10) As Integer
Dim mdr As Integer
mp = 0
Do
mdr = IIf(n > 0, 1, 0)
While n > 0
mdr *= n Mod base_
n = n \ base_
Wend
mp += 1
n = mdr
Loop until mdr < base_
Return mdr
End Funct... |
http://rosettacode.org/wiki/Dragon_curve | Dragon curve |
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by a left dragon, at 90-degree an... | #Visual_Basic | Visual Basic | Option Explicit
Const Pi As Double = 3.14159265358979
Dim angle As Double
Dim nDepth As Integer
Dim nColor As Long
Private Sub Form_Load()
nColor = vbBlack
nDepth = 12
DragonCurve
End Sub
Sub DragonProc(size As Double, ByVal split As Integer, d As Integer)
If split = 0 Then
xForm.Line -Step(-Co... |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of... | #Crystal | Crystal | module Enumerable(T)
def index!(element)
index(element).not_nil!
end
end
residents = [:Baker, :Cooper, :Fletcher, :Miller, :Smith]
predicates = [
->(p : Array(Symbol)){ :Baker != p.last },
->(p : Array(Symbol)){ :Cooper != p.first },
->(p : Array(Symbol)){ :Fletcher != p.first && :Fletch... |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #Cowgol | Cowgol | include "cowgol.coh";
sub dotproduct(a: [int32], b: [int32], len: intptr): (n: int32) is
n := 0;
while len > 0 loop
n := n + [a] * [b];
a := @next a;
b := @next b;
len := len - 1;
end loop;
end sub;
sub printsgn(n: int32) is
if n<0 then
print_char('-');
... |
http://rosettacode.org/wiki/Doubly-linked_list/Definition | Doubly-linked list/Definition | Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | #PowerShell | PowerShell |
$list = New-Object -TypeName 'Collections.Generic.LinkedList[PSCustomObject]'
for($i=1; $i -lt 10; $i++)
{
$list.AddLast([PSCustomObject]@{ID=$i; X=100+$i;Y=200+$i}) | Out-Null
}
$list
|
http://rosettacode.org/wiki/Dice_game_probabilities | Dice game probabilities | Two players have a set of dice each. The first player has nine dice with four faces each, with numbers one to four. The second player has six normal dice with six faces each, each face has the usual numbers from one to six.
They roll their dice and sum the totals of the faces. The player with the highest total wins (i... | #J | J | gen_dict =: (({. , #)/.~@:,@:(+/&>)@:{@:(# <@:>:@:i.)~ ; ^)&x:
beating_probability =: dyad define
'C0 P0' =. gen_dict/ x
'C1 P1' =. gen_dict/ y
(C0 +/@:,@:(>/&:({."1) * */&:({:"1)) C1) % (P0 * P1)
) |
http://rosettacode.org/wiki/Dice_game_probabilities | Dice game probabilities | Two players have a set of dice each. The first player has nine dice with four faces each, with numbers one to four. The second player has six normal dice with six faces each, each face has the usual numbers from one to six.
They roll their dice and sum the totals of the faces. The player with the highest total wins (i... | #Java | Java | import java.util.Random;
public class Dice{
private static int roll(int nDice, int nSides){
int sum = 0;
Random rand = new Random();
for(int i = 0; i < nDice; i++){
sum += rand.nextInt(nSides) + 1;
}
return sum;
}
private static int diceGame(int p1Dice, int p1Sides, int p2Dice, int p2Sides, int roll... |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #C.23 | C# | using System;
using System.Net;
using System.Net.Sockets;
class Program {
static void Main(string[] args) {
try {
TcpListener server = new TcpListener(IPAddress.Any, 12345);
server.Start();
}
catch (SocketException e) {
if (e.SocketErr... |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #C.2B.2B | C++ | #include <afx.h> |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #Clojure | Clojure | (import (java.net ServerSocket InetAddress))
(def *port* 12345) ; random large port number
(try (new ServerSocket *port* 10 (. InetAddress getLocalHost))
(catch IOException e (System/exit 0))) ; port taken, so app is already running |
http://rosettacode.org/wiki/Dining_philosophers | Dining philosophers | The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a rou... | #Common_Lisp | Common Lisp | (in-package :common-lisp-user)
;;
;; FLAG -- if using quicklisp, you can get bordeaux-threads loaded up
;; with: (ql:quickload :bordeaux-threads)
;;
(defvar *philosophers* '(Aristotle Kant Spinoza Marx Russell))
(defclass philosopher ()
((name :initarg :name :reader name-of)
(left-fork :initarg :left-fork :... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #Befunge | Befunge | 0" :raeY">:#,_&>\" :htnoM">:#,_&>04p" :yaD">:#,_$&>55+,1-:47*v
v"f I".+1%,,,,"Day I":$_:#<0#!4#:p#-4#1g4-#0+#<<_v#!*!-2g40!-<
>"o",,,/:5+*66++:4>g#<:#44#:9#+*#1-#,_$$0 v_v#!< >$ 0 "yaD " v
@,+55.+*+92"j"$_,#!>#:<", in the YOLD"*84 <.>,:^ :"St. Tib's"<
$# #"#"##"#"Chaos$Discord$Confusion$Bureaucracy$The Aftermath$ |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path pro... | #Clojure | Clojure |
(declare neighbours
process-neighbour
prepare-costs
get-next-node
unwind-path
all-shortest-paths)
;; Main algorithm
(defn dijkstra
"Given two nodes A and B, and graph, finds shortest path from point A to point B.
Given one node and graph, finds all shortest pat... |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displ... | #BBC_BASIC | BBC BASIC | *FLOAT64
PRINT "Digital root of 627615 is "; FNdigitalroot(627615, 10, p) ;
PRINT " (additive persistence " ; p ")"
PRINT "Digital root of 39390 is "; FNdigitalroot(39390, 10, p) ;
PRINT " (additive persistence " ; p ")"
PRINT "Digital root of 588225 is "; FNdigitalroot(588225, 10, p... |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displ... | #Befunge | Befunge | 0" :rebmun retnE">:#,_0 0v
v\1:/+55p00<v\`\0::-"0"<~<
#>:55+%00g+^>9`+#v_+\ 1+\^
>|`9:p000<_v#`1\$< v"gi"<
|> \ 1 + \ >0" :toor lat"^
>$$00g\1+^@,+<v"Di",>#+ 5<
>:#,_$ . 5 5 ^>:#,_\.55+,v
^"Additive Persistence: "< |
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
... | #Go | Go | package main
import "fmt"
// Only valid for n > 0 && base >= 2
func mult(n uint64, base int) (mult uint64) {
for mult = 1; mult > 0 && n > 0; n /= uint64(base) {
mult *= n % uint64(base)
}
return
}
// Only valid for n >= 0 && base >= 2
func MultDigitalRoot(n uint64, base int) (mp, mdr int) {
var m uint64
f... |
http://rosettacode.org/wiki/Dragon_curve | Dragon curve |
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by a left dragon, at 90-degree an... | #Visual_Basic_.NET | Visual Basic .NET | Option Explicit On
Imports System.Math
Public Class DragonCurve
Dim nDepth As Integer = 12
Dim angle As Double
Dim MouseX, MouseY As Integer
Dim CurrentX, CurrentY As Integer
Dim nColor As Color = Color.Black
Private Sub DragonCurve_Click(sender As Object, e As EventArgs) Handles Me.Click
... |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of... | #D | D | import std.stdio, std.math, std.algorithm, std.traits, permutations2;
void main() {
enum Names { Baker, Cooper, Fletcher, Miller, Smith }
immutable(bool function(in Names[]) pure nothrow)[] predicates = [
s => s[Names.Baker] != s.length - 1,
s => s[Names.Cooper] != 0,
s => s[Names.Fl... |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #Crystal | Crystal | class Vector
property x, y, z
def initialize(@x : Int64, @y : Int64, @z : Int64) end
def dot_product(other : Vector)
(self.x * other.x) + (self.y * other.y) + (self.z * other.z)
end
end
puts Vector.new(1, 3, -5).dot_product Vector.new(4, -2, -1) # => 3
class Array
def dot_product(other)
raise ... |
http://rosettacode.org/wiki/Doubly-linked_list/Definition | Doubly-linked list/Definition | Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | #PureBasic | PureBasic | DataSection
;the list of words that will be added to the list
words:
Data.s "One", "Two", "Three", "Four", "Five", "Six", "EndOfData"
EndDataSection
Procedure displayList(List x.s(), title$)
;display all elements from list of strings
Print(title$)
ForEach x()
Print(x() + " ")
Next
PrintN("")
E... |
http://rosettacode.org/wiki/Dice_game_probabilities | Dice game probabilities | Two players have a set of dice each. The first player has nine dice with four faces each, with numbers one to four. The second player has six normal dice with six faces each, each face has the usual numbers from one to six.
They roll their dice and sum the totals of the faces. The player with the highest total wins (i... | #JacaScript | JacaScript |
let Player = function(dice, faces) {
this.dice = dice;
this.faces = faces;
this.roll = function() {
let results = [];
for (let x = 0; x < dice; x++)
results.push(Math.floor(Math.random() * faces +1));
return eval(results.join('+'));
}
}
function contest(player1, player2, rounds) {
let re... |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #D | D |
bool is_unique_instance()
{
import std.socket;
auto socket = new Socket(AddressFamily.UNIX, SocketType.STREAM);
auto addr = new UnixAddress("\0/tmp/myapp.uniqueness.sock");
try
{
socket.bind(addr);
return true;
}
catch (SocketOSException e)
{
import core.stdc.er... |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #Delphi | Delphi | program OneInstance;
{$APPTYPE CONSOLE}
uses SysUtils, Windows;
var
FMutex: THandle;
begin
FMutex := CreateMutex(nil, True, 'OneInstanceMutex');
if FMutex = 0 then
RaiseLastOSError
else
begin
try
if GetLastError = ERROR_ALREADY_EXISTS then
Writeln('Program already running. Closing... |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #Erlang | Erlang | 7> erlang:register( aname, erlang:self() ).
true
8> erlang:register( aname, erlang:self() ).
** exception error: bad argument
in function register/2
called as register(aname,<0.42.0>)
|
http://rosettacode.org/wiki/Dining_philosophers | Dining philosophers | The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a rou... | #D | D | import std.stdio, std.algorithm, std.string, std.parallelism,
core.sync.mutex;
void eat(in size_t i, in string name, Mutex[] forks) {
writeln(name, " is hungry.");
immutable j = (i + 1) % forks.length;
// Take forks i and j. The lower one first to prevent deadlock.
auto fork1 = forks[min(i, j... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #C | C | #include <stdlib.h>
#include <stdio.h>
#include <time.h>
#define day_of_week( x ) ((x) == 1 ? "Sweetmorn" :\
(x) == 2 ? "Boomtime" :\
(x) == 3 ? "Pungenday" :\
(x) == 4 ? "Prickle-Prickle" :\
"Setting Orange")
#d... |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path pro... | #Commodore_BASIC | Commodore BASIC | 100 NV=0: REM NUMBER OF VERTICES
110 READ N$:IF N$<>"" THEN NV=NV+1:GOTO 110
120 NE=0: REM NUMBER OF EDGES
130 READ N1:IF N1 >= 0 THEN READ N2,W:NE=NE+1:GOTO 130
140 DIM VN$(NV-1),VD(NV-1,2): REM VERTEX NAMES AND DATA
150 DIM ED(NE-1,2): REM EDGE DATA
160 RESTORE
170 FOR I=0 TO NV-1
180 : READ VN$(I): REM VERTEX NAME
... |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displ... | #BQN | BQN | DSum ← +´10{⌽𝕗|⌊∘÷⟜𝕗⍟(↕1+·⌊𝕗⋆⁼1⌈⊢)}
Root ← 0⊸{(×○⌊÷⟜10)◶⟨𝕨‿𝕩,(1+𝕨)⊸𝕊 Dsum⟩𝕩}
P ← •Show ⊢∾Root
P 627615
P 39390
P 588225
P 393900588225 |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displ... | #Bracmat | Bracmat | ( root
= sum persistence n d
. !arg:(~>9.?)
| !arg:(?n.?persistence)
& 0:?sum
& ( @( !n
: ?
(#%@?d&!d+!sum:?sum&~)
?
)
| root$(!sum.!persistence+1)
)
)
& ( 627615 39390 588225 393900588225 10 199
... |
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
... | #Haskell | Haskell | import Control.Arrow
import Data.Array
import Data.LazyArray
import Data.List (unfoldr)
import Data.Tuple
import Text.Printf
-- The multiplicative persistence (MP) and multiplicative digital root (MDR) of
-- the argument.
mpmdr :: Integer -> (Int, Integer)
mpmdr = (length *** head) . span (> 9) . iterate (product . d... |
http://rosettacode.org/wiki/Dragon_curve | Dragon curve |
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by a left dragon, at 90-degree an... | #Wren | Wren | import "graphics" for Canvas, Color
import "dome" for Window
class Game {
static init() {
Window.title = "Dragon curve"
Window.resize(800, 600)
Canvas.resize(800, 600)
var iter = 14
var turns = getSequence(iter)
var startingAngle = -iter * Num.pi / 4
var side... |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of... | #EchoLisp | EchoLisp |
(require 'hash)
(require' amb)
;;
;; Solver
;;
(define (dwelling-puzzle context names floors H)
;; each amb calls gives a floor to a name
(for ((name names))
(hash-set H name (amb context floors)))
;; They live on different floors.
(amb-require (distinct? (amb-choices context)))
(constraints floors ... |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #D | D | void main() {
import std.stdio, std.numeric;
[1.0, 3.0, -5.0].dotProduct([4.0, -2.0, -1.0]).writeln;
} |
http://rosettacode.org/wiki/Doubly-linked_list/Definition | Doubly-linked list/Definition | Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | #Python | Python |
from collections import deque
some_list = deque(["a", "b", "c"])
print(some_list)
some_list.appendleft("Z")
print(some_list)
for value in reversed(some_list):
print(value)
|
http://rosettacode.org/wiki/Dice_game_probabilities | Dice game probabilities | Two players have a set of dice each. The first player has nine dice with four faces each, with numbers one to four. The second player has six normal dice with six faces each, each face has the usual numbers from one to six.
They roll their dice and sum the totals of the faces. The player with the highest total wins (i... | #jq | jq | # To take advantage of gojq's arbitrary-precision integer arithmetic:
def power($b): . as $in | reduce range(0;$b) as $i (1; . * $in);
# Input: an array (aka: counts)
def throwDie($nSides; $nDice; $s):
if $nDice == 0
then .[$s] += 1
else reduce range(1; $nSides + 1) as $i (.;
throwDie($nSides; $nDice-1; $s... |
http://rosettacode.org/wiki/Dice_game_probabilities | Dice game probabilities | Two players have a set of dice each. The first player has nine dice with four faces each, with numbers one to four. The second player has six normal dice with six faces each, each face has the usual numbers from one to six.
They roll their dice and sum the totals of the faces. The player with the highest total wins (i... | #Julia | Julia | play(ndices::Integer, nfaces::Integer) = (nfaces, ndices) ∋ 0 ? 0 : sum(rand(1:nfaces) for i in 1:ndices)
simulate(d1::Integer, f1::Integer, d2::Integer, f2::Integer; nrep::Integer=1_000_000) =
mean(play(d1, f1) > play(d2, f2) for _ in 1:nrep)
println("\nPlayer 1: 9 dices, 4 faces\nPlayer 2: 6 dices, 6 faces\nP... |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #FreeBASIC | FreeBASIC | Shell("tasklist > temp.txt")
Dim linea As String
Open "temp.txt" For Input As #1
Do While Not Eof(1)
Line Input #1, linea
If Instr(linea, "fbc.exe") = 0 Then Print "Task is Running" : Exit Do
Loop
Close #1
Shell("del temp.txt")
Sleep |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #Go | Go | package main
import (
"fmt"
"net"
"time"
)
const lNet = "tcp"
const lAddr = ":12345"
func main() {
if _, err := net.Listen(lNet, lAddr); err != nil {
fmt.Println("an instance was already running")
return
}
fmt.Println("single instance started")
time.Sleep(10 * time.Seco... |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #Haskell | Haskell | import Control.Concurrent
import System.Directory (doesFileExist, getAppUserDataDirectory,
removeFile)
import System.IO (withFile, Handle, IOMode(WriteMode), hPutStr)
oneInstance :: IO ()
oneInstance = do
-- check if file "$HOME/.myapp.lock" exists
user <- getAppUserDataDirectory "myapp.lock"
locked <... |
http://rosettacode.org/wiki/Dining_philosophers | Dining philosophers | The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a rou... | #Delphi | Delphi |
program dining_philosophers;
uses
Classes,
SysUtils,
SyncObjs;
const
PHIL_COUNT = 5;
LIFESPAN = 7;
DELAY_RANGE = 950;
DELAY_LOW = 50;
PHIL_NAMES: array[1..PHIL_COUNT] of string = ('Aristotle', 'Kant', 'Spinoza', 'Marx', 'Russell');
type
TFork = TCriticalSection;
// TPhilosopher =... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #C.23 | C# | using System;
public static class DiscordianDate
{
static readonly string[] seasons = { "Chaos", "Discord", "Confusion", "Bureaucracy", "The Aftermath" };
static readonly string[] weekdays = { "Sweetmorn", "Boomtime", "Pungenday", "Prickle-Prickle", "Setting Orange" };
static readonly string[] apostles = ... |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path pro... | #Common_Lisp | Common Lisp |
(defparameter *w* '((a (a b . 7) (a c . 9) (a f . 14))
(b (b c . 10) (b d . 15))
(c (c d . 11) (c f . 2))
(d (d e . 6))
(e (e f . 9))))
(defvar *r* nil)
(defun dijkstra-short-path (i g)
(setf *r* nil) (paths i g 0 `(,i))
(car (sor... |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displ... | #C | C | #include <stdio.h>
int droot(long long int x, int base, int *pers)
{
int d = 0;
if (pers)
for (*pers = 0; x >= base; x = d, (*pers)++)
for (d = 0; x; d += x % base, x /= base);
else if (x && !(d = x % (base - 1)))
d = base - 1;
return d;
}
int main(void)
{
int i, d, pers;
long long x[] = {627615, 39... |
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
... | #Icon_and_Unicon | Icon and Unicon | procedure main(A)
write(right("n",8)," ",right("MP",8),right("MDR",5))
every r := mdr(n := 123321|7739|893|899998) do
write(right(n,8),":",right(r[1],8),right(r[2],5))
write()
write(right("MDR",5)," ","[n0..n4]")
every m := 0 to 9 do {
writes(right(m,5),": [")
every writes(r... |
http://rosettacode.org/wiki/Dragon_curve | Dragon curve |
Create and display a dragon curve fractal.
(You may either display the curve directly or write it to an image file.)
Algorithms
Here are some brief notes the algorithms used and how they might suit various languages.
Recursively a right curling dragon is a right dragon followed by a left dragon, at 90-degree an... | #X86_Assembly | X86 Assembly | .model tiny
.code
.486
org 100h ;assume ax=0, bx=0, sp=-2
start: mov al, 13h ;(ah=0) set 320x200 video graphics mode
int 10h
push 0A000h
pop es
mov si, 8000h ;color
mov cx, 75*256+100 ;coordi... |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of... | #Elixir | Elixir | defmodule Dinesman do
def problem do
names = ~w( Baker Cooper Fletcher Miller Smith )a
predicates = [fn(c)-> :Baker != List.last(c) end,
fn(c)-> :Cooper != List.first(c) end,
fn(c)-> :Fletcher != List.first(c) && :Fletcher != List.last(c) end,
fn(c)-> floo... |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #Dart | Dart | num dot(List<num> A, List<num> B){
if (A.length != B.length){
throw new Exception('Vectors must be of equal size');
}
num result = 0;
for (int i = 0; i < A.length; i++){
result += A[i] * B[i];
}
return result;
}
void main(){
var l = [1,3,-5];
var k = [4,-2,-1];
print(dot(l,k));
} |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #Delphi | Delphi | program Project1;
{$APPTYPE CONSOLE}
type
doublearray = array of Double;
function DotProduct(const A, B : doublearray): Double;
var
I: integer;
begin
assert (Length(A) = Length(B), 'Input arrays must be the same length');
Result := 0;
for I := 0 to Length(A) - 1 do
Result := Result + (A[I] * B[I]);
en... |
http://rosettacode.org/wiki/Doubly-linked_list/Definition | Doubly-linked list/Definition | Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | #Racket | Racket |
#lang racket
(define-struct dlist (head tail) #:mutable #:transparent)
(define-struct dlink (content prev next) #:mutable #:transparent)
(define (insert-between dlist before after data)
; Insert a fresh link containing DATA after existing link
; BEFORE if not nil and before existing link AFTER if not nil
(de... |
http://rosettacode.org/wiki/Dice_game_probabilities | Dice game probabilities | Two players have a set of dice each. The first player has nine dice with four faces each, with numbers one to four. The second player has six normal dice with six faces each, each face has the usual numbers from one to six.
They roll their dice and sum the totals of the faces. The player with the highest total wins (i... | #Kotlin | Kotlin | // version 1.1.2
fun throwDie(nSides: Int, nDice: Int, s: Int, counts: IntArray) {
if (nDice == 0) {
counts[s]++
return
}
for (i in 1..nSides) throwDie(nSides, nDice - 1, s + i, counts)
}
fun beatingProbability(nSides1: Int, nDice1: Int, nSides2: Int, nDice2: Int): Double {
val len1 ... |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #Icon_and_Unicon | Icon and Unicon | procedure main(A)
if not open(":"||54321,"na") then stop("Already running")
repeat {} # busy loop
end |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #Java | Java | import java.io.IOException;
import java.net.InetAddress;
import java.net.ServerSocket;
import java.net.UnknownHostException;
public class SingletonApp
{
private static final int PORT = 65000; // random large port number
private static ServerSocket s;
// static initializer
static {
try {
... |
http://rosettacode.org/wiki/Dining_philosophers | Dining philosophers | The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a rou... | #E | E |
(lib 'tasks)
(define names #(Aristotle Kant Spinoza Marx Russell))
(define abouts #("Wittgenstein" "the nature of the World" "Kant" "starving"
"spaghettis" "the essence of things" "Ω" "📞" "⚽️" "🍅" "🌿"
"philosophy" "💔" "👠" "rosetta code" "his to-do list" ))
(define (about) (format "thinking about %a... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #C.2B.2B | C++ |
#include <iostream>
#include <algorithm>
#include <vector>
#include <sstream>
#include <iterator>
using namespace std;
class myTuple
{
public:
void set( int a, int b, string c ) { t.first.first = a; t.first.second = b; t.second = c; }
bool operator == ( pair<int, int> p ) { return p.first == t.first.first && ... |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path pro... | #D | D | import std.stdio, std.typecons, std.algorithm, std.container;
alias Vertex = string;
alias Weight = int;
struct Neighbor {
Vertex target;
Weight weight;
}
alias AdjacencyMap = Neighbor[][Vertex];
pure dijkstraComputePaths(Vertex source, Vertex target, AdjacencyMap adjacencyMap){
Weight[Vertex] minDi... |
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