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/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... | #Crystal | Crystal | def digital_root(n : Int, base = 10) : Int
max_single_digit = base - 1
n = n.abs
if n > max_single_digit
n = 1 + (n - 1) % max_single_digit
end
n
end
puts digital_root 627615
puts digital_root 39390
puts digital_root 588225
puts digital_root 7, base: 3 |
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
... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language |
ClearAll[mdr, mp, nums];
mdr[n_] := NestWhile[Times @@ IntegerDigits[#] &, n, # > 9 &];
mp[n_] := Length@NestWhileList[Times @@ IntegerDigits[#] &, n, # > 9 &] - 1;
TableForm[{#, mdr[#], mp[#]} & /@ {123321, 7739, 893, 899998},
TableHeadings -> {None, {"Number", "MDR", "MP"}}]
nums = ConstantArray[{}, 10];
For[i = ... |
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... | #Haskell | Haskell | import Data.List (permutations)
import Control.Monad (guard)
dinesman :: [(Int,Int,Int,Int,Int)]
dinesman = do
-- baker, cooper, fletcher, miller, smith are integers representing
-- the floor that each person lives on, from 1 to 5
-- Baker, Cooper, Fletcher, Miller, and Smith live on different floors
-- of... |
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 ... | #Elixir | Elixir | defmodule Vector do
def dot_product(a,b) when length(a)==length(b), do: dot_product(a,b,0)
def dot_product(_,_) do
raise ArgumentError, message: "Vectors must have the same length."
end
defp dot_product([],[],product), do: product
defp dot_product([h1|t1], [h2|t2], product), do: dot_product(t1, t2, prod... |
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 ... | #Elm | Elm | dotp: List number -> List number -> Maybe number
dotp a b =
if List.length a /= List.length b then
Nothing
else
Just (List.sum <| List.map2 (*) a b)
dotp [1,3,-5] [4,-2,-1]) |
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead... | #BASIC | BASIC | 10 DEFINT A-Z
20 READ N: DIM S$(N): FOR I=1 TO N: READ S$(I): NEXT
30 READ S,C$: IF S=0 THEN END
40 PRINT "Character: '";C$;"'"
50 O$=S$(S): GOSUB 200
60 I$=S$(S): GOSUB 100: GOSUB 200
70 PRINT
80 GOTO 30
100 REM --
101 REM -- Squeeze I$ on character C$, output in O$
102 REM --
105 O$ = ""
110 X = INSTR(I$,C$)
120 IF X... |
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead... | #BCPL | BCPL | get "libhdr"
// Squeeze a string
let squeeze(in, ch, out) = valof
$( out%0 := 0
for i=1 to in%0
if i=1 | in%i~=ch | in%(i-1)~=ch
$( out%0 := out%0 + 1
out%(out%0) := in%i
$)
resultis out
$)
// Print string with brackets and length
let brackets(s) be
writef("%N: <<<%... |
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... | #8th | 8th | : number? >n >kind ns:n n:= ; |
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... | #AArch64_Assembly | AArch64 Assembly |
/* ARM assembly Raspberry PI */
/* program strNumber.s */
/*******************************************/
/* Constantes file */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly*/
.include "../includeConstantesARM64.inc"
... |
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... | #Tcl | Tcl | package require Tcl 8.4
proc dl {_name cmd {where error} {value ""}} {
upvar 1 $_name N
switch -- $cmd {
insert {
if ![info exists N()] {set N() {"" "" 0}}
set id [lindex $N() 2]
lset N() 2 [incr id]
switch -- $where {
head {
... |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_unique_characters | Determine if a string has all unique characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are unique
indicate if or which character is duplicated and where
display each string and its length (as the strings are being ... | #11l | 11l | F processString(input)
[Char = Int] charMap
V dup = Char("\0")
V index = 0
V pos1 = -1
V pos2 = -1
L(key) input
index++
I key C charMap
dup = key
pos1 = charMap[key]
pos2 = index
L.break
charMap[key] = index
V unique = I dup == Char("\0") {‘yes’... |
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediatel... | #APL | APL | task←{
⍝ Collapse a string
collapse←{(1,¯1↓⍵≠1⌽⍵)/⍵}
⍝ Given a function ⍺⍺, display a string in brackets,
⍝ along with its length, and do the same for the result
⍝ of applying ⍺⍺ to the string.
display←{
bracket←{(⍕⍴⍵),' «««',⍵,'»»»'}
↑(⊂bracket ⍵),(⊂bracket ⍺⍺ ⍵)
}
⍝ Strings fro... |
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediatel... | #Arturo | Arturo | lines: [
{::}
{:"If I were two-faced, would I be wearing this one?" --- Abraham Lincoln :}
{:..1111111111111111111111111111111111111111111111111111111111111117777888:}
{:I never give 'em hell, I just tell the truth, and they think it's hell. :}
{: -... |
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... | #Python | Python | from itertools import product
def gen_dict(n_faces, n_dice):
counts = [0] * ((n_faces + 1) * n_dice)
for t in product(range(1, n_faces + 1), repeat=n_dice):
counts[sum(t)] += 1
return counts, n_faces ** n_dice
def beating_probability(n_sides1, n_dice1, n_sides2, n_dice2):
c1, p1 = gen_dict(n... |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_the_same_characters | Determine if a string has all the same characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are the same
indicate if or which character is different from the previous character
display each string and its length (as the... | #Arturo | Arturo | strings: [
"", " ", "2", "333", ".55", "tttTTT",
"4444 444k", "pépé", "🐶🐶🐺🐶", "🎄🎄🎄🎄"
]
allSameChars?: function [str][
if empty? str -> return ø
current: first str
loop.with:'i str 'ch [
if ch <> current -> return i
]
return ø
]
loop strings 's [
prints ["\"" ++ s... |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_the_same_characters | Determine if a string has all the same characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are the same
indicate if or which character is different from the previous character
display each string and its length (as the... | #AutoHotkey | AutoHotkey | testCases := ["", " ", "2", "333", ".55", "tttTTT", "4444 4444k"]
for key, str in testCases {
MsgBox % "Examining `'" str "`' which has a length of " StrLen(str) ":`n"
if (StrLen(str) == 0) or (StrLen(str) == 1) {
MsgBox % " All characters in the string are the same.`n"
continue
}
firstChar := SubStr(str, 1,... |
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.
| #Ring | Ring |
# Project : Determine if only one instance is running
task = "ringw.exe"
taskname = "tasklist.txt"
remove(taskname)
system("tasklist >> tasklist.txt")
fp = fopen(taskname,"r")
tasks = read("tasklist.txt")
counttask = count(tasks,task)
if counttask > 0
see task + " running in " + counttask + " instances" + nl
els... |
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.
| #Ruby | Ruby | def main
puts "first instance"
sleep 20
puts :done
end
if $0 == __FILE__
if File.new(__FILE__).flock(File::LOCK_EX | File::LOCK_NB)
main
else
raise "another instance of this program is running"
end
end
__END__ |
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running | Determine if only one instance is running | This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.
| #Run_BASIC | Run BASIC | if instr(shell$("tasklist"),"rbp.exe") <> 0 then print "Task is Running" |
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.
| #Rust | Rust | use std::net::TcpListener;
fn create_app_lock(port: u16) -> TcpListener {
match TcpListener::bind(("0.0.0.0", port)) {
Ok(socket) => {
socket
},
Err(_) => {
panic!("Couldn't lock port {}: another instance already running?", port);
}
}
}
fn remove_app_l... |
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... | #Go | Go | package main
import (
"hash/fnv"
"log"
"math/rand"
"os"
"time"
)
// Number of philosophers is simply the length of this list.
// It is not otherwise fixed in the program.
var ph = []string{"Aristotle", "Kant", "Spinoza", "Marx", "Russell"}
const hunger = 3 // number of times eac... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #Fortran | Fortran |
program discordianDate
implicit none
! Declare variables
character(32) :: arg
character(15) :: season,day,holyday
character(80) :: Output,fmt1,fmt2,fmt3
character(2) :: dayfix,f1,f2,f3,f4
integer :: i,j,k,daysofyear,dayofweek,seasonnum,yold,dayofseason,t1,t2,t3
integer,dimension(8) :: ... |
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... | #Icon_and_Unicon | Icon and Unicon | procedure main(A)
graph := getGraph()
repeat {
writes("What is the start node? ")
start := \graph.nodes[read()] | stop()
writes("What is the finish node? ")
finish := read() | stop()
QMouse(graph,start,finish)
waitForCompletion() # block until all quantum mice h... |
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... | #D | D | import std.stdio, std.typecons, std.conv, std.bigint, std.math,
std.traits;
Tuple!(uint, Unqual!T) digitalRoot(T)(in T inRoot, in uint base)
pure nothrow
in {
assert(base > 1);
} body {
Unqual!T root = inRoot.abs;
uint persistence = 0;
while (root >= base) {
auto num = root;
roo... |
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
... | #Nim | Nim | import strutils, sequtils, sugar
proc mdroot(n: int): tuple[mp, mdr: int] =
var mdr = @[n]
while mdr[mdr.high] > 9:
var n = 1
for dig in $mdr[mdr.high]:
n *= parseInt($dig)
mdr.add n
(mdr.high, mdr[mdr.high])
for n in [123321, 7739, 893, 899998]:
echo align($n, 6)," ",mdroot(n)
echo ""
v... |
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... | #Icon_and_Unicon | Icon and Unicon | invocable all
global nameL, nameT, rules
procedure main() # Dinesman
nameT := table()
nameL := ["Baker", "Cooper", "Fletcher", "Miller", "Smith"]
rules := [ [ distinct ],
[ "~=", "Baker", top() ],
[ "~=", "Cooper", bottom() ],
[ "~=", "Fletcher", top... |
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 ... | #Emacs_Lisp | Emacs Lisp | (defun dot-product (v1 v2)
(let ((res 0))
(dotimes (i (length v1))
(setq res (+ (* (elt v1 i) (elt v2 i)) res)))
res))
(dot-product [1 2 3] [1 2 3]) ;=> 14
(dot-product '(1 2 3) '(1 2 3)) ;=> 14 |
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead... | #C | C |
#include<string.h>
#include<stdlib.h>
#include<stdio.h>
#define COLLAPSE 0
#define SQUEEZE 1
typedef struct charList{
char c;
struct charList *next;
} charList;
/*
Implementing strcmpi, the case insensitive string comparator, as it is not part of the C Standard Library.
Comment this out if testing on ... |
http://rosettacode.org/wiki/Determine_if_two_triangles_overlap | Determine if two triangles overlap | Determining if two triangles in the same plane overlap is an important topic in collision detection.
Task
Determine which of these pairs of triangles overlap in 2D:
(0,0),(5,0),(0,5) and (0,0),(5,0),(0,6)
(0,0),(0,5),(5,0) and (0,0),(0,5),(5,0)
(0,0),(5,0),(0,5) and (-10,0),(-5,0),(-1,6)... | #11l | 11l | T Triangle
(Float, Float) p1, p2, p3
F (p1, p2, p3)
.p1 = p1
.p2 = p2
.p3 = p3
F String()
R ‘Triangle: #., #., #.’.format(.p1, .p2, .p3)
F.const det2D()
R .p1[0] * (.p2[1] - .p3[1])
+ .p2[0] * (.p3[1] - .p1[1])
+ .p3[0] * (.p1[1] - .p2[1])
F checkTriWinding(... |
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
... | #11l | 11l | F s_permutations(seq)
V items = [[Int]()]
L(j) seq
[[Int]] new_items
L(item) items
V i = L.index
I i % 2
new_items [+]= (0 .. item.len).map(i -> @item[0 .< i] [+] [@j] [+] @item[i ..])
E
new_items [+]= (item.len .< -1).step(-1).map(i -> @item[0 .< i] ... |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #68000_Assembly | 68000 Assembly |
1 0 n:/ Inf? . cr
|
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... | #Action.21 | Action! | INCLUDE "D2:REAL.ACT" ;from the Action! Tool Kit
BYTE FUNC AreEqual(CHAR ARRAY a,b)
BYTE i
IF a(0)#b(0) THEN
RETURN (0)
FI
FOR i=1 to a(0)
DO
IF a(i)#b(i) THEN
RETURN (0)
FI
OD
RETURN (1)
BYTE FUNC IsNumeric(CHAR ARRAY s)
CHAR ARRAY tmp(20)
INT i
CARD c
REAL r
i=ValI(s)
... |
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... | #ActionScript | ActionScript | public function isNumeric(num:String):Boolean
{
return !isNaN(parseInt(num));
} |
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... | #Visual_Basic_.NET | Visual Basic .NET | Public Class DoubleLinkList(Of T)
Private m_Head As Node(Of T)
Private m_Tail As Node(Of T)
Public Sub AddHead(ByVal value As T)
Dim node As New Node(Of T)(Me, value)
If m_Head Is Nothing Then
m_Head = Node
m_Tail = m_Head
Else
node.Next = m_Head
... |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_unique_characters | Determine if a string has all unique characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are unique
indicate if or which character is duplicated and where
display each string and its length (as the strings are being ... | #Action.21 | Action! | PROC PrintBH(BYTE a)
BYTE ARRAY hex=['0 '1 '2 '3 '4 '5 '6 '7 '8 '9 'A 'B 'C 'D 'E 'F]
Put(hex(a RSH 4))
Put(hex(a&$0F))
RETURN
PROC Test(CHAR ARRAY s)
BYTE i,j,n,pos1,pos2
pos1=0 pos2=0
n=s(0)-1
IF n=255 THEN n=0 FI
FOR i=1 TO n
DO
FOR j=i+1 TO s(0)
DO
IF s(j)=s(i) THEN
pos... |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_unique_characters | Determine if a string has all unique characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are unique
indicate if or which character is duplicated and where
display each string and its length (as the strings are being ... | #Ada | Ada | with Ada.Integer_Text_IO; use Ada.Integer_Text_IO;
with Ada.Text_IO; use Ada.Text_IO;
procedure Test_All_Chars_Unique is
procedure All_Chars_Unique (S : in String) is
begin
Put_Line ("Input = """ & S & """, length =" & S'Length'Image);
for I in S'First .. S'Last - 1 loop
for J in I + 1 .. S'L... |
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediatel... | #AutoHotkey | AutoHotkey | collapsible_string(str){
for i, ch in StrSplit(str){
if (ch <> prev)
res .= ch
prev := ch
}
return "original string:`t" StrLen(str) " characters`t«««" str "»»»`nresultant string:`t" StrLen(res) " characters`t«««" res "»»»"
} |
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediatel... | #AWK | AWK |
# syntax: GAWK -f DETERMINE_IF_A_STRING_IS_COLLAPSIBLE.AWK
BEGIN {
for (i=1; i<=9; i++) {
for (j=1; j<=i; j++) {
arr[0] = arr[0] i
}
}
arr[++n] = ""
arr[++n] = "\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln "
arr[++n] = "..111111111111111111111111111... |
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... | #R | R | probability <- function(facesCount1, diceCount1, facesCount2, diceCount2)
{
mean(replicate(10^6, sum(sample(facesCount1, diceCount1, replace = TRUE)) > sum(sample(facesCount2, diceCount2, replace = TRUE))))
}
cat("Player 1's probability of victory is", probability(4, 9, 6, 6),
"in the first game and", probability... |
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... | #Racket | Racket | #lang racket
(define probs# (make-hash))
(define (NdD n d)
(hash-ref!
probs# (cons n d)
(λ ()
(cond
[(= n 0) ; every chance of nothing!
(hash 0 1)]
[else
(for*/fold ((hsh (hash))) (((i p) (in-hash (NdD (sub1 n) d))) (r (in-range 1 (+ d 1))))
(hash-update hsh (+ r... |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_the_same_characters | Determine if a string has all the same characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are the same
indicate if or which character is different from the previous character
display each string and its length (as the... | #AWK | AWK |
# syntax: GAWK -f DETERMINE_IF_A_STRING_HAS_ALL_THE_SAME_CHARACTERS.AWK
BEGIN {
for (i=0; i<=255; i++) { ord_arr[sprintf("%c",i)] = i } # build array[character]=ordinal_value
n = split(", ,2,333,.55,tttTTT,4444 444k",arr,",")
for (i in arr) {
width = max(width,length(arr[i]))
}
width += 2
... |
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.
| #Scala | Scala | import java.io.IOException
import java.net.{InetAddress, ServerSocket}
object SingletonApp extends App {
private val port = 65000
try {
val s = new ServerSocket(port, 10, InetAddress.getLocalHost)
}
catch {
case _: IOException =>
// port taken, so app is already running
println("Applicat... |
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.
| #Sidef | Sidef | # For this to work, you need to explicitly
# store the returned fh inside a variable.
var fh = File(__FILE__).open_r
# Now call the flock() method on it
fh.flock(File.LOCK_EX | File.LOCK_NB) ->
|| die "I'm already running!"
# Your code here...
say "Running..."
Sys.sleep(20)
say 'Done!' |
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.
| #Swift | Swift | import Foundation
let globalCenter = NSDistributedNotificationCenter.defaultCenter()
let time = NSDate().timeIntervalSince1970
globalCenter.addObserverForName("OnlyOne", object: nil, queue: NSOperationQueue.mainQueue()) {not in
if let senderTime = not.userInfo?["time"] as? NSTimeInterval where senderTime != tim... |
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.
| #Tcl | Tcl | package require Tcl 8.6
try {
# Pick a port number based on the name of the main script executing
socket -server {apply {{chan args} {close $chan}}} -myaddr localhost \
[expr {1024 + [zlib crc32 [file normalize $::argv0]] % 30000}]
} trap {POSIX EADDRINUSE} {} {
# Generate a nice error message
... |
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... | #Groovy | Groovy | import groovy.transform.Canonical
import java.util.concurrent.locks.Lock
import java.util.concurrent.locks.ReentrantLock
@Canonical
class Fork {
String name
Lock lock = new ReentrantLock()
void pickUp(String philosopher) {
lock.lock()
println " $philosopher picked up $name"
}
... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #FreeBASIC | FreeBASIC | #Include "datetime.bi"
meses:
Data "Chaos", "Discord", "Confusion", "Bureaucracy", "The Aftermath"
dias_laborales:
Data "Setting Orange", "Sweetmorn", "Boomtime", "Pungenday", "Prickle-Prickle"
dias_previos_al_1er_mes:
' ene feb mar abr may jun jul ago sep oct nov dic
Data 0, 31, 59, 90, 120, 151, 181, 212, ... |
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... | #J | J |
NB. verbs and adverb
parse_table=: ;:@:(LF&= [;._2 -.&CR)
mp=: $:~ :(+/ .*) NB. matrix product
min=: <./ NB. minimum
Index=: (i.`)(`:6) NB. Index adverb
dijkstra=: dyad define
'LINK WEIGHT'=. , (0 _ ,. 2) <;.3 y
'SOURCE SINK'=. |: LINK
F... |
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... | #Dc | Dc | ?[10~rd10<p]sp[+z1<q]sq[lpxlqxd10<r]dsrxp |
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... | #DCL | DCL | $ x = p1
$ count = 0
$ sum = x
$ loop1:
$ length = f$length( x )
$ if length .eq. 1 then $ goto done
$ i = 0
$ sum = 0
$ loop2:
$ digit = f$extract( i, 1, x )
$ sum = sum + digit
$ i = i + 1
$ if i .lt. length then $ goto loop2
$ x = f$string( sum )
$ count = count + 1
$ goto loop1
$ done:
$ write sys$o... |
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
... | #PARI.2FGP | PARI/GP | a(n)=my(i);while(n>9,n=factorback(digits(n));i++);[i,n];
apply(a, [123321, 7739, 893, 899998])
v=vector(10,i,[]); forstep(n=0,oo,1, t=a(n)[2]+1; if(#v[t]<5,v[t]=concat(v[t],n); if(vecmin(apply(length,v))>4, return(v)))) |
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... | #J | J | possible=: ((i.!5) A. i.5) { 'BCFMS' |
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 ... | #Erlang | Erlang | dotProduct(A,B) when length(A) == length(B) -> dotProduct(A,B,0);
dotProduct(_,_) -> erlang:error('Vectors must have the same length.').
dotProduct([H1|T1],[H2|T2],P) -> dotProduct(T1,T2,P+H1*H2);
dotProduct([],[],P) -> P.
dotProduct([1,3,-5],[4,-2,-1]). |
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead... | #C.23 | C# | using System;
using static System.Linq.Enumerable;
public class Program
{
static void Main()
{
SqueezeAndPrint("", ' ');
SqueezeAndPrint("\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ", '-');
SqueezeAndPrint("..1111111111111111111111111111111111111111111111... |
http://rosettacode.org/wiki/Determine_if_two_triangles_overlap | Determine if two triangles overlap | Determining if two triangles in the same plane overlap is an important topic in collision detection.
Task
Determine which of these pairs of triangles overlap in 2D:
(0,0),(5,0),(0,5) and (0,0),(5,0),(0,6)
(0,0),(0,5),(5,0) and (0,0),(0,5),(5,0)
(0,0),(5,0),(0,5) and (-10,0),(-5,0),(-1,6)... | #Ada | Ada |
WITH Ada.Text_IO; USE Ada.Text_IO;
PROCEDURE Main IS
TYPE Vertex IS MOD 3;
TYPE Point IS ARRAY (0 .. 1) OF Float;
TYPE Triangle IS ARRAY (Vertex) OF Point;
TYPE Triangle_Vertices IS ARRAY (0 .. 5) OF Float;
FUNCTION Same_Side (A, B, M, N : Point) RETURN Boolean IS
FUNCTION Aff (U : Point) RET... |
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
... | #360_Assembly | 360 Assembly | * Matrix arithmetic 13/05/2016
MATARI START
STM R14,R12,12(R13) save caller's registers
LR R12,R15 set R12 as base register
USING MATARI,R12 notify assembler
LA R11,SAVEAREA get the address of my savearea
ST R13,4(... |
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
... | #Arturo | Arturo | printMatrix: function [m][
loop m 'row -> print map row 'val [pad to :string .format:".2f" val 6]
print "--------------------------------"
]
permutations: function [arr][
d: 1
c: array.of: size arr 0
xs: new arr
sign: 1
ret: new @[@[xs, sign]]
while [true][
while [d > 1][
... |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #8th | 8th |
1 0 n:/ Inf? . cr
|
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #ABAP | ABAP | report zdiv_zero
data x type i.
try.
x = 1 / 0.
catch CX_SY_ZERODIVIDE.
write 'Divide by zero.'.
endtry.
|
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... | #Ada | Ada | package Numeric_Tests is
function Is_Numeric (Item : in String) return Boolean;
end Numeric_Tests; |
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... | #Aime | Aime | integer
is_numeric(text s)
{
return !trap_q(alpha, s, 0);
}
integer
main(void)
{
if (!is_numeric("8192&*")) {
o_text("Not numeric.\n");
}
if (is_numeric("8192")) {
o_text("Numeric.\n");
}
return 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... | #Wren | Wren | import "/llist" for DLinkedList
var dll = DLinkedList.new()
for (i in 1..3) dll.add(i)
System.print(dll)
for (i in 1..3) dll.remove(i)
System.print(dll) |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_unique_characters | Determine if a string has all unique characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are unique
indicate if or which character is duplicated and where
display each string and its length (as the strings are being ... | #ALGOL_68 | ALGOL 68 | BEGIN
# mode to hold the positions of duplicate characters in a string #
MODE DUPLICATE = STRUCT( INT original, first duplicate );
# finds the first non-unique character in s and returns its position #
# and the position of the original character in a DUPLICATE #
# if all characters... |
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediatel... | #BaCon | BaCon | DATA ""
DATA "\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln "
DATA "..1111111111111111111111111111111111111111111111111111111111111117777888"
DATA "I never give 'em hell, I just tell the truth, and they think it's hell. "
DATA " --- Harry S ... |
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediatel... | #BASIC | BASIC | 10 READ N%
20 FOR A% = 1 TO N%
30 READ I$: GOSUB 100
40 PRINT LEN(I$); "<<<"; I$; ">>>"
50 PRINT LEN(O$); "<<<"; O$; ">>>"
55 PRINT
60 NEXT
70 END
100 REM Collapse I$ into O$
105 IF I$="" THEN O$=I$: RETURN
110 O$=SPACE$(LEN(I$))
120 P$=LEFT$(I$,1)
130 MID$(O$,1,1)=P$
140 O%=2
150 FOR I%=2 TO LEN(I$)
160 C$=MID$(I$,I%,... |
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... | #Raku | Raku | sub likelihoods ($roll) {
my ($dice, $faces) = $roll.comb(/\d+/);
my @counts;
@counts[$_]++ for [X+] |(1..$faces,) xx $dice;
return [@counts[]:p], $faces ** $dice;
}
sub beating-probability ([$roll1, $roll2]) {
my (@c1, $p1) := likelihoods $roll1;
my (@c2, $p2) := likelihoods $roll2;
my $p... |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_the_same_characters | Determine if a string has all the same characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are the same
indicate if or which character is different from the previous character
display each string and its length (as the... | #BASIC | BASIC |
10 'SAVE"SAMECHAR", A
20 DEFINT A-Z
30 DATA ""," ","2","333",".55","tttTTT","4444 444k", "FIN"
40 ' Main program cycle
50 CLS
60 PRINT "Program SameChar"
70 PRINT "Determines if a string has the same character or not."
80 PRINT
90 WHILE S$<>"FIN"
100 READ S$
110 IF S$="FIN" THEN 150
120 GOSUB 190 ' Revision ... |
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.
| #TXR | TXR | ;;; Define some typedefs for clear correspondence with Win32
(typedef HANDLE cptr)
(typedef LPSECURITY_ATTRIBUTES cptr)
(typedef WINERR (enum WINERR ERROR_SUCCESS
(ERROR_ALREADY_EXISTS 183)))
(typedef BOOL (enum BOOL FALSE TRUE))
(typedef LPCWSTR wstr)
;;; More familiar spelling for null... |
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.
| #UNIX_Shell | UNIX Shell |
# (c) Copyright 2005 Mark Hobley
#
# This is free software. This file can be redistributed or modified
# under the terms of version 1.2 of the GNU Free Documentation Licence
# as published by the Free Software Foundation.
#
singleinstance ()
{
if [ -d $SRUNDIR ] ; then
if [ -w $SRUNDIR ] ; then
if ... |
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.
| #Visual_Basic | Visual Basic | Dim onlyInstance as Boolean
onlyInstance = not App.PrevInstance |
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.
| #Wren | Wren | import "io" for File, FileFlags
var specialFile = "wren-exclusive._sp"
var checkOneInstanceRunning = Fn.new {
// attempt to create the special file with exclusive access
var ff = FileFlags.create | FileFlags.exclusive
File.openWithFlags(specialFile, ff) { |file| } // closes automatically if successful
}
... |
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... | #Haskell | Haskell | module Philosophers where
import Control.Monad
import Control.Concurrent
import Control.Concurrent.STM
import System.Random
-- TMVars are transactional references. They can only be used in transactional actions.
-- They are either empty or contain one value. Taking an empty reference fails and
-- putting a value in... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #Go | Go | package ddate
import (
"strconv"
"strings"
"time"
)
// Predefined formats for DiscDate.Format
const (
DefaultFmt = "Pungenday, Discord 5, 3131 YOLD"
OldFmt = `Today is Pungenday, the 5th day of Discord in the YOLD 3131
Celebrate Mojoday`
)
// Formats passed to DiscDate.Format are proty... |
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... | #Java | Java |
import java.io.*;
import java.util.*;
public class Dijkstra {
private static final Graph.Edge[] GRAPH = {
new Graph.Edge("a", "b", 7),
new Graph.Edge("a", "c", 9),
new Graph.Edge("a", "f", 14),
new Graph.Edge("b", "c", 10),
new Graph.Edge("b", "d", 15),
new Graph.Edge("c", "d"... |
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... | #Delphi | Delphi |
class
APPLICATION
inherit
ARGUMENTS
create
make
feature {NONE} -- Initialization
digital_root_test_values: ARRAY [INTEGER_64]
-- Test values.
once
Result := <<670033, 39390, 588225, 393900588225>> -- base 10
end
digital_root_expected_result: ARRAY [INTEGER_64]
-- Expected result values.
... |
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
... | #Pascal | Pascal | program MultRoot;
{$IFDEF FPC}
{$MODE DELPHI}{$OPTIMIZATION ON,ALL}{$CODEALIGN proc=16}
{$ENDIF}
{$IFDEF WINDOWS}
{$APPTYPE CONSOLE}
{$ENDIF}
uses
sysutils;
type
tMul3Dgt = array[0..999] of Uint32;
tMulRoot = record
mrNum,
mrMul,
mrPers : Uint64;
end;
... |
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... | #Java | Java | import java.util.*;
class DinesmanMultipleDwelling {
private static void generatePermutations(String[] apartmentDwellers, Set<String> set, String curPermutation) {
for (String s : apartmentDwellers) {
if (!curPermutation.contains(s)) {
String nextPermutation = curPermutation ... |
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 ... | #Euphoria | Euphoria | function dotprod(sequence a, sequence b)
atom sum
a *= b
sum = 0
for n = 1 to length(a) do
sum += a[n]
end for
return sum
end function
? dotprod({1,3,-5},{4,-2,-1}) |
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead... | #C.2B.2B | C++ | #include <algorithm>
#include <string>
#include <iostream>
template<typename char_type>
std::basic_string<char_type> squeeze(std::basic_string<char_type> str, char_type ch) {
auto i = std::unique(str.begin(), str.end(),
[ch](char_type a, char_type b) { return a == ch && b == ch; });
str.erase(i, str.e... |
http://rosettacode.org/wiki/Descending_primes | Descending primes | Generate and show all primes with strictly descending decimal digits.
See also
OEIS:A052014 - Primes with distinct digits in descending order
Related
Ascending primes
| #ALGOL_68 | ALGOL 68 | BEGIN # find all primes with strictly decreasing digits #
PR read "primes.incl.a68" PR # include prime utilities #
PR read "rows.incl.a68" PR # include array utilities #
[ 1 : 512 ]INT primes; # there will be at most 512 (2^9) primes #
... |
http://rosettacode.org/wiki/Determine_if_two_triangles_overlap | Determine if two triangles overlap | Determining if two triangles in the same plane overlap is an important topic in collision detection.
Task
Determine which of these pairs of triangles overlap in 2D:
(0,0),(5,0),(0,5) and (0,0),(5,0),(0,6)
(0,0),(0,5),(5,0) and (0,0),(0,5),(5,0)
(0,0),(5,0),(0,5) and (-10,0),(-5,0),(-1,6)... | #ALGOL_W | ALGOL W | begin % determine if two triangles overlap %
record Point ( real x, y );
record Triangle ( reference(Point) p1, p2, p3 );
procedure WritePoint ( reference(Point) value p ) ;
writeon( r_w := 3, r_d := 1, r_format := "A", s_w := 0, "(", x(p), ", ", y(p), ")" );
procedure WriteTriangle ( referen... |
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
... | #C | C | #include <stdio.h>
#include <stdlib.h>
#include <string.h>
double det_in(double **in, int n, int perm)
{
if (n == 1) return in[0][0];
double sum = 0, *m[--n];
for (int i = 0; i < n; i++)
m[i] = in[i + 1] + 1;
for (int i = 0, sgn = 1; i <= n; i++) {
sum += sgn * (in[i][0] * det_in(m, n, perm));
if (i == ... |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #Ada | Ada | -- Divide By Zero Detection
with Ada.Text_Io; use Ada.Text_Io;
with Ada.Float_Text_Io; use Ada.Float_Text_Io;
with Ada.Integer_Text_Io; use Ada.Integer_Text_Io;
procedure Divide_By_Zero is
Fnum : Float := 1.0;
Fdenom : Float := 0.0;
Fresult : Float;
Inum : Integer := 1;
Idenom : Integer := 0;
Ires... |
http://rosettacode.org/wiki/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #Aime | Aime | integer
divide(integer n, integer d)
{
return n / d;
}
integer
can_divide(integer n, integer d)
{
return !trap(divide, n, d);
}
integer
main(void)
{
if (!can_divide(9, 0)) {
o_text("Division by zero.\n");
}
return 0;
} |
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... | #ALGOL_68 | ALGOL 68 | PROC is numeric = (REF STRING string) BOOL: (
BOOL out := TRUE;
PROC call back false = (REF FILE f)BOOL: (out:= FALSE; TRUE);
FILE memory;
associate(memory, string);
on value error(memory, call back false);
on logical file end(memory, call back false);
UNION (INT, REAL, COMPL) numeric:=0.0;
# use a ... |
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... | #zkl | zkl | class Node{
fcn init(_value,_prev=Void,_next=Void)
{ var value=_value, prev=_prev, next=_next; }
fcn toString{ value.toString() }
fcn append(value){ // loops not allowed: create a new Node
b,c := Node(value,self,next),next;
next=b;
if(c) c.prev=b;
b
}
fcn delete{
if(... |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_unique_characters | Determine if a string has all unique characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are unique
indicate if or which character is duplicated and where
display each string and its length (as the strings are being ... | #AppleScript | AppleScript | use AppleScript version "2.4"
use framework "Foundation"
use scripting additions
on run
script showSource
on |λ|(s)
quoted("'", s) & " (" & length of s & ")"
end |λ|
end script
script showDuplicate
on |λ|(mb)
script go
on |λ|(tpl)
... |
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediatel... | #BCPL | BCPL | get "libhdr"
// Collapse a string
let collapse(in, out) = valof
$( let o = 0
for i = 1 to in%0
unless i>1 & in%i = in%(i-1)
$( o := o + 1
out%o := in%i
$)
out%0 := o
resultis out
$)
// Print string with brackets and length
let brackets(s) be
writef("%N: <<<%S>>>... |
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediatel... | #Bracmat | Bracmat | ( colapse
= previous
. str
$ ( vap
$ ( (
=
. !arg:!previous&
| !arg:?previous
)
. !arg
)
)
)
& ( testcolapse
= len
. (len=.@(!arg:? [?arg)&!arg)
& out$(str$(««« !arg "»»» " len$!arg))
& ... |
http://rosettacode.org/wiki/Determine_if_a_string_is_collapsible | Determine if a string is collapsible | Determine if a character string is collapsible.
And if so, collapse the string (by removing immediately repeated characters).
If a character string has immediately repeated character(s), the repeated characters are to be
deleted (removed), but not the primary (1st) character(s).
An immediatel... | #C | C |
#include<string.h>
#include<stdlib.h>
#include<stdio.h>
#define COLLAPSE 0
#define SQUEEZE 1
typedef struct charList{
char c;
struct charList *next;
} charList;
/*
Implementing strcmpi, the case insensitive string comparator, as it is not part of the C Standard Library.
Comment this out if testing on ... |
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... | #REXX | REXX | /* REXX */
Numeric Digits 30
Call test '9 4 6 6'
Call test '5 10 6 7'
Exit
test:
Parse Arg w1 s1 w2 s2
plist1=pp(w1,s1)
p1.=0
Do x=w1 To w1*s1
Parse Var plist1 p1.x plist1
End
plist2=pp(w2,s2)
p2.=0
Do x=w2 To w2*s2
Parse Var plist2 p2.x plist2
End
p2low.=0
Do x=w1 To w1*s1
Do y=0 To x-1
p2low.x=p2low.x+p... |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_the_same_characters | Determine if a string has all the same characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are the same
indicate if or which character is different from the previous character
display each string and its length (as the... | #BCPL | BCPL | get "libhdr"
let diffchar(s) = valof
$( for i=2 to s%0
unless s%i = s%1 resultis i
resultis 0
$)
let show(s) be
$( let i = diffchar(s)
writef("*"%S*" (length %N): ", s, s%0)
test i=0
do writes("all the same.*N")
or writef("'%C' at index %N.*N", s%i, i)
$)
let start() be
$( s... |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_the_same_characters | Determine if a string has all the same characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are the same
indicate if or which character is different from the previous character
display each string and its length (as the... | #C | C |
#include<string.h>
#include<stdio.h>
int main(int argc,char** argv)
{
int i,len;
char reference;
if(argc>2){
printf("Usage : %s <Test String>\n",argv[0]);
return 0;
}
if(argc==1||strlen(argv[1])==1){
printf("Input string : \"%s\"\nLength : %d\nAll characters are ident... |
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... | #Icon_and_Unicon | Icon and Unicon | global forks, names
procedure main(A)
names := ["Aristotle","Kant","Spinoza","Marks","Russell"]
write("^C to terminate")
nP := *names
forks := [: |mutex([])\nP :]
every p := !nP do thread philosopher(p)
delay(-1)
end
procedure philosopher(n)
f1 := forks[min(n, n%*forks+1)]
f2 := fork... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #Haskell | Haskell | import Data.Time (isLeapYear)
import Data.Time.Calendar.MonthDay (monthAndDayToDayOfYear)
import Text.Printf (printf)
type Year = Integer
type Day = Int
type Month = Int
data DDate = DDate Weekday Season Day Year
| StTibsDay Year deriving (Eq, Ord)
data Season = Chaos
| Discord
... |
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... | #JavaScript | JavaScript |
const dijkstra = (edges,source,target) => {
const Q = new Set(),
prev = {},
dist = {},
adj = {}
const vertex_with_min_dist = (Q,dist) => {
let min_distance = Infinity,
u = null
for (let v of Q) {
if (dist[v] < min_distance) {
... |
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... | #Eiffel | Eiffel |
class
APPLICATION
inherit
ARGUMENTS
create
make
feature {NONE} -- Initialization
digital_root_test_values: ARRAY [INTEGER_64]
-- Test values.
once
Result := <<670033, 39390, 588225, 393900588225>> -- base 10
end
digital_root_expected_result: ARRAY [INTEGER_64]
-- Expected result values.
... |
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
... | #Perl | Perl | use warnings;
use strict;
sub mdr {
my $n = shift;
my($count, $mdr) = (0, $n);
while ($mdr > 9) {
my($m, $dm) = ($mdr, 1);
while ($m) {
$dm *= $m % 10;
$m = int($m/10);
}
$mdr = $dm;
$count++;
}
($count, $mdr);
}
print "Number: (MP, MDR)\n====== =========\n";
foreach my $n... |
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... | #JavaScript | JavaScript | (() => {
'use strict';
// concatMap :: (a -> [b]) -> [a] -> [b]
const concatMap = (f, xs) => [].concat.apply([], xs.map(f));
// range :: Int -> Int -> [Int]
const range = (m, n) =>
Array.from({
length: Math.floor(n - m) + 1
}, (_, i) => m + i);
// and :: [Bool] ... |
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 ... | #F.23 | F# | let dot_product (a:array<'a>) (b:array<'a>) =
if Array.length a <> Array.length b then failwith "invalid argument: vectors must have the same lengths"
Array.fold2 (fun acc i j -> acc + (i * j)) 0 a b |
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