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... | #Forth | Forth | : (Sdigit) 0 swap begin base @ /mod >r + r> dup 0= until drop ;
: digiroot 0 swap begin (Sdigit) >r 1+ r> dup base @ < until ; |
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... | #Fortran | Fortran |
program prec
implicit none
integer(kind=16) :: i
i = 627615
call root_pers(i)
i = 39390
call root_pers(i)
i = 588225
call root_pers(i)
i = 393900588225
call root_pers(i)
end program
subroutine root_pers(i)
implicit none
integer(kind=16) :: N, s, a, i
write(*,*) 'Number: ', i
n = i
a = 0
do while(n.ge.10)
a = a + ... |
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
... | #Quackery | Quackery | [ abs 1 swap
[ base share /mod
rot * swap
dup 0 = until ]
drop ] is digitproduct ( n --> n )
[ 0 swap
[ dup base share > while
dip 1+
digitproduct again ] ] is mdr ( n --> n n )
[ dup mdr
rot echo
say ": "
swap echo
... |
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
... | #Racket | Racket | #lang racket
(define (digital-product n)
(define (inr-d-p m rv)
(cond
[(zero? m) rv]
[else (define-values (q r) (quotient/remainder m 10))
(if (zero? r) 0 (inr-d-p q (* rv r)))])) ; lazy on zero
(inr-d-p n 1))
(define (mdr/mp n)
(define (inr-mdr/mp m i)
(if (< m 10) (values m 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... | #Kotlin | Kotlin | // version 1.1.3
typealias Predicate = (List<String>) -> Boolean
fun <T> permute(input: List<T>): List<List<T>> {
if (input.size == 1) return listOf(input)
val perms = mutableListOf<List<T>>()
val toInsert = input[0]
for (perm in permute(input.drop(1))) {
for (i in 0..perm.size) {
... |
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 ... | #FunL | FunL | import lists.zipWith
def dot( a, b )
| a.length() == b.length() = sum( zipWith((*), a, b) )
| otherwise = error( "Vector sizes must match" )
println( dot([1, 3, -5], [4, -2, -1]) ) |
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 ... | #FreeBASIC | FreeBASIC | #define NAN 0.0/0.0 'dot product of different-dimensioned vectors is no more defined than 0/0
function dot( a() as double, b() as double ) as double
if ubound(a)<>ubound(b) then return NAN
dim as uinteger i
dim as double dp = 0.0
for i = 0 to ubound(a)
dp += a(i)*b(i)
next i
retur... |
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... | #FreeBASIC | FreeBASIC |
function squeeze(byval s as string,target as string) as string
dim as string g
dim as long n
for n =0 to len(s)-2
if s[n]=asc(target) then
if s[n]<>s[n+1] then g+=chr(s[n])
else
g+=chr(s[n])
end if
next n
if len(s) then g+=chr(s... |
http://rosettacode.org/wiki/Deming%27s_Funnel | Deming's Funnel | W Edwards Deming was an American statistician and management guru who used physical demonstrations to illuminate his teachings. In one demonstration Deming repeatedly dropped marbles through a funnel at a target, marking where they landed, and observing the resulting pattern. He applied a sequence of "rules" to try to ... | #Elixir | Elixir | defmodule Deming do
def funnel(dxs, rule) do
{_, rxs} = Enum.reduce(dxs, {0, []}, fn dx,{x,rxs} ->
{rule.(x, dx), [x + dx | rxs]}
end)
rxs
end
def mean(xs), do: Enum.sum(xs) / length(xs)
def stddev(xs) do
m = mean(xs)
Enum.reduce(xs, 0.0, fn x,sum -> sum + (x-m)*(x-m) / length(xs) ... |
http://rosettacode.org/wiki/Deming%27s_Funnel | Deming's Funnel | W Edwards Deming was an American statistician and management guru who used physical demonstrations to illuminate his teachings. In one demonstration Deming repeatedly dropped marbles through a funnel at a target, marking where they landed, and observing the resulting pattern. He applied a sequence of "rules" to try to ... | #Factor | Factor | USING: combinators formatting generalizations grouping.extras io
kernel math math.statistics sequences ;
: show ( seq1 seq2 -- )
[ [ mean ] bi@ ] [ [ population-std ] bi@ ] 2bi
"Mean x, y : %.4f, %.4f\nStd dev x, y : %.4f, %.4f\n"
printf ;
{
-0.533 0.270 0.859 -0.043 -0.205 -0.127 -0.071 0.275... |
http://rosettacode.org/wiki/Department_numbers | Department numbers | There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (different from each other) and mu... | #8080_Assembly | 8080 Assembly | org 100h
lxi h,obuf ; HL = output buffer
mvi b,2 ; B = police
pol: mvi c,1 ; C = sanitation
san: mvi d,1 ; D = fire
fire: mov a,b ; Fire equal to police?
cmp d
jz next ; If so, invalid combination
mov a,c ; Fire equal to sanitation?
cmp d
jz next ; If so, invalid combination
mov a,b ; Total equal to 12?
add c... |
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
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | Sort[Select[FromDigits/@Subsets[Range[9,1,-1],{1,\[Infinity]}],PrimeQ]] |
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
| #Perl | Perl | #!/usr/bin/perl
use strict; # https://rosettacode.org/wiki/Descending_primes
use warnings;
use ntheory qw( is_prime );
print join('', sort map { sprintf "%9d", $_ } grep /./ && is_prime($_),
glob join '', map "{$_,}", reverse 1 .. 9) =~ s/.{45}\K/\n/gr; |
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
| #Phix | Phix | with javascript_semantics
function descending_primes(sequence res, atom p=0, max_digit=9)
for d=1 to max_digit do
atom np = p*10+d
if odd(d) and is_prime(np) then res &= np end if
res = descending_primes(res,np,d-1)
end for
return res
end function
sequence r = sort(descending_prime... |
http://rosettacode.org/wiki/Delegates | Delegates | A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See also wp:Delegation pattern.
Objects ... | #Ada | Ada | with Ada.Text_IO; use Ada.Text_IO;
procedure Delegation is
package Things is
-- We need a common root for our stuff
type Object is tagged null record;
type Object_Ptr is access all Object'Class;
-- Objects that have operation thing
type Substantial is new Object with null record;
... |
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)... | #D | D | import std.stdio;
import std.typecons;
alias Pair = Tuple!(real, real);
struct Triangle {
Pair p1;
Pair p2;
Pair p3;
void toString(scope void delegate(const(char)[]) sink) const {
import std.format;
sink("Triangle: ");
formattedWrite!"%s"(sink, p1);
sink(", ");
... |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Action.21 | Action! | PROC Dir(CHAR ARRAY filter)
CHAR ARRAY line(255)
BYTE dev=[1]
Close(dev)
Open(dev,filter,6)
DO
InputSD(dev,line)
PrintE(line)
IF line(0)=0 THEN
EXIT
FI
OD
Close(dev)
RETURN
PROC DeleteFile(CHAR ARRAY fname)
BYTE dev=[1]
Close(dev)
Xio(dev,0,33,0,0,fname)
RETURN
PROC Mai... |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Ada | Ada | with Ada.Directories; use Ada.Directories; |
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
... | #EchoLisp | EchoLisp |
(lib 'list)
(lib 'matrix)
;; adapted from Racket
(define (permanent M)
(let (( n (matrix-row-num M)))
(for/sum ([σ (in-permutations n)])
(for/product ([i n] [σi σ])
(array-ref M i σi)))))
;; output
(define A (list->array '(1 2 3 4) 2 2))
(array-print A)
1 2
3 4
(determinant A) → ... |
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.
| #C | C | #include <limits.h> /* INT_MIN */
#include <setjmp.h> /* siglongjmp(), sigsetjmp() */
#include <stdio.h> /* perror(), printf() */
#include <stdlib.h> /* exit() */
#include <signal.h> /* sigaction(), sigemptyset() */
static sigjmp_buf fpe_env;
/*
* This SIGFPE handler jumps to fpe_env.
*
* A SIGFPE handler must 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... | #AWK | AWK |
$ awk 'function isnum(x){return(x==x+0)} BEGIN{print isnum("hello"),isnum("-42")}'
|
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 ... | #C.2B.2B | C++ | #include <iostream>
#include <string>
void string_has_repeated_character(const std::string& str) {
size_t len = str.length();
std::cout << "input: \"" << str << "\", length: " << len << '\n';
for (size_t i = 0; i < len; ++i) {
for (size_t j = i + 1; j < len; ++j) {
if (str[i] == str[j]... |
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... | #Factor | Factor | USING: formatting io kernel sbufs sequences strings ;
IN: rosetta-code.string-collapse
: (collapse) ( str -- str )
unclip-slice 1string >sbuf
[ over last over = [ drop ] [ suffix! ] if ] reduce >string ;
: collapse ( str -- str ) [ "" ] [ (collapse) ] if-empty ;
: .str ( str -- ) dup length "«««%s»»» (len... |
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... | #FreeBASIC | FreeBASIC | Const numCad = 5
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 " ... |
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... | #zkl | zkl | fcn combos(sides, n){
if(not n) return(T(1));
ret:=((0).max(sides)*n + 1).pump(List(),0);
foreach i,v in (combos(sides, n - 1).enumerate()){
if(not v) continue;
foreach s in (sides){ ret[i + s] += v }
}
ret
}
fcn winning(sides1,n1, sides2,n2){
p1, p2 := combos(sides1, n1), combos(sides2,... |
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... | #Delphi | Delphi |
program Determine_if_a_string_has_all_the_same_characters;
{$APPTYPE CONSOLE}
uses
System.SysUtils;
procedure Analyze(s: string);
var
b, c: char;
i: Integer;
begin
writeln(format('Examining [%s] which has a length of %d:', [s, s.Length]));
if s.Length > 1 then
begin
b := s[1];
for i := 2 to ... |
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... | #Kotlin | Kotlin | // Version 1.2.31
import java.util.Random
import java.util.concurrent.locks.Lock
import java.util.concurrent.locks.ReentrantLock
val rand = Random()
class Fork(val name: String) {
val lock = ReentrantLock()
fun pickUp(philosopher: String) {
lock.lock()
println(" $philosopher picked up $... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #JotaCode | JotaCode | @print(
"Today is ",
@let(1,@add(@switch(@time("mon"),
0,-1,
1,30,
2,58,
3,89,
4,119,
5,150,
6,180,
7,211,
8,242,
9,272,
10,303,
11,333)
,@time("mday")),@switch(@print(@time("mon"),"/",@time("mday")),
"1/29","St. Tib's Day",
@print(@switch(@mod("%1",5),
0,"S... |
http://rosettacode.org/wiki/Dijkstra%27s_algorithm | Dijkstra's algorithm | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path pro... | #M2000_Interpreter | M2000 Interpreter |
Module Dijkstra`s_algorithm {
const max_number=1.E+306
GetArr=lambda (n, val)->{
dim d(n)=val
=d()
}
term=("",0)
Edges=(("a", ("b",7),("c",9),("f",14)),("b",("c",10),("d",15)),("c",("d",11),("f",2)),("d",("e",6)),("e",("f", 9)),("f",term))
Document Doc$="Graph:"+{
}
ShowGraph()
Doc$="Paths"+{
}
Print "... |
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... | #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Function digitalRoot(n As UInteger, ByRef ap As Integer, base_ As Integer = 10) As Integer
Dim dr As Integer
ap = 0
Do
dr = 0
While n > 0
dr += n Mod base_
n = n \ base_
Wend
ap += 1
n = dr
Loop until dr < base_
Return dr
End Function
Dim As Integer dr, ... |
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
... | #Raku | Raku | sub multiplicative-digital-root(Int $n) {
return .elems - 1, .[.end]
given cache($n, {[*] .comb} ... *.chars == 1)
}
for 123321, 7739, 893, 899998 {
say "$_: ", .&multiplicative-digital-root;
}
for ^10 -> $d {
say "$d : ", .[^5]
given (1..*).grep: *.&multiplicative-digital-root[1] == $d;... |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of... | #Lua | Lua | local wrap, yield = coroutine.wrap, coroutine.yield
local function perm(n)
local r = {}
for i=1,n do r[i]=i end
return wrap(function()
local function swap(m)
if m==0 then
yield(r)
else
for i=m,1,-1 do
r[i],r[m]=r[m],r[i]
swap(m-1)
r[i],... |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #F.C5.8Drmul.C3.A6 | Fōrmulæ | # Built-in
[1, 3, -5]*[4, -2, -1];
# 3 |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #GAP | GAP | # Built-in
[1, 3, -5]*[4, -2, -1];
# 3 |
http://rosettacode.org/wiki/Determine_if_a_string_is_squeezable | Determine if a string is squeezable | Determine if a character string is squeezable.
And if so, squeeze the string (by removing any number of
a specified immediately repeated character).
This task is very similar to the task Determine if a character string is collapsible except
that only a specified character is squeezed instead... | #Frink | Frink | squeeze[str, ch] :=
{
println["Use: '$ch'"]
println["old: " + length[str] + " <<<$str>>>"]
str =~ subst["($ch)\\1+", "$$1", "g"]
println["new: " + length[str] + " <<<$str>>>"]
}
lines = [["", [""]],
[""""If I were two-faced, would I be wearing this one?" --- Abraham Lincoln """, ["-"]],
["..11111... |
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... | #Go | Go | package main
import "fmt"
// Returns squeezed string, original and new lengths in
// unicode code points (not normalized).
func squeeze(s string, c rune) (string, int, int) {
r := []rune(s)
le, del := len(r), 0
for i := le - 2; i >= 0; i-- {
if r[i] == c && r[i] == r[i+1] {
copy(r[i:... |
http://rosettacode.org/wiki/Deming%27s_Funnel | Deming's Funnel | W Edwards Deming was an American statistician and management guru who used physical demonstrations to illuminate his teachings. In one demonstration Deming repeatedly dropped marbles through a funnel at a target, marking where they landed, and observing the resulting pattern. He applied a sequence of "rules" to try to ... | #Go | Go | package main
import (
"fmt"
"math"
)
type rule func(float64, float64) float64
var dxs = []float64{
-0.533, 0.270, 0.859, -0.043, -0.205, -0.127, -0.071, 0.275,
1.251, -0.231, -0.401, 0.269, 0.491, 0.951, 1.150, 0.001,
-0.382, 0.161, 0.915, 2.080, -2.337, 0.034, -0.126, 0.014,
... |
http://rosettacode.org/wiki/Department_numbers | Department numbers | There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (different from each other) and mu... | #8086_Assembly | 8086 Assembly | cpu 8086
bits 16
org 100h
section .text
mov di,obuf ; Output buffer
mov bl,2 ; BL = police
pol: mov cl,1 ; CL = sanitation
san: mov dl,1 ; DL = fire
fire: cmp bl,cl ; Police equal to sanitation?
je next ; Invalid combination
cmp bl,dl ; Police equal to fire?
je next ; Invalid combination
cmp cl,dl ; S... |
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
| #Picat | Picat | import util.
main =>
DP = [N : S in power_set("987654321"), S != [], N = S.to_int, prime(N)].sort,
foreach({P,I} in zip(DP,1..DP.len))
printf("%9d%s",P,cond(I mod 10 == 0,"\n",""))
end,
nl,
println(len=DP.len). |
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
| #Python | Python | from sympy import isprime
def descending(xs=range(10)):
for x in xs:
yield x
yield from descending(x*10 + d for d in range(x%10))
for i, p in enumerate(sorted(filter(isprime, descending()))):
print(f'{p:9d}', end=' ' if (1 + i)%8 else '\n')
print() |
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
| #Raku | Raku | put (flat 2, 3, 5, 7, sort +*, gather (3..9).map: &recurse ).batch(10)».fmt("%8d").join: "\n";
sub recurse ($str) {
.take for ($str X~ (1, 3, 7)).grep: { .is-prime && [>] .comb };
recurse $str × 10 + $_ for 2 ..^ $str % 10;
} |
http://rosettacode.org/wiki/Delegates | Delegates | A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See also wp:Delegation pattern.
Objects ... | #Aikido | Aikido |
class Delegator {
public generic delegate = none
public function operation {
if (typeof(delegate) == "none") {
return "default implementation"
}
return delegate()
}
}
function thing {
return "delegate implementation"
}
// default, no delegate
var d = new Deleg... |
http://rosettacode.org/wiki/Delegates | Delegates | A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See also wp:Delegation pattern.
Objects ... | #Aime | Aime | text
thing(void)
{
return "delegate implementation";
}
text
operation(record delegator)
{
text s;
if (r_key(delegator, "delegate")) {
if (r_key(delegator["delegate"], "thing")) {
s = call(r_query(delegator["delegate"], "thing"));
} else {
s = "default implementati... |
http://rosettacode.org/wiki/Delegates | Delegates | A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See also wp:Delegation pattern.
Objects ... | #ALGOL_68 | ALGOL 68 | # An Algol 68 approximation of delegates #
# The delegate mode - the delegate is a STRUCT with a single field #
# that is a REF PROC STRING. If this is NIL, it doesn't implement #
# thing #
MODE DELEGATE = STRUC... |
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)... | #Delphi | Delphi | open System
type Point = double * double
type Triangle = Point * Point * Point
let Det2D (t:Triangle) =
let (p1, p2, p3) = t
let (p1x, p1y) = p1
let (p2x, p2y) = p2
let (p3x, p3y) = p3
p1x * (p2y - p3y) +
p2x * (p3y - p1y) +
p3x * (p1y - p2y)
let CheckTriWinding allowReversed t =
... |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Aikido | Aikido |
remove ("input.txt")
remove ("/input.txt")
remove ("docs")
remove ("/docs")
|
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Aime | Aime | remove("input.txt");
remove("/input.txt");
remove("docs");
remove("/docs"); |
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
... | #Factor | Factor | USING: fry kernel math.combinatorics math.matrices sequences ;
: permanent ( matrix -- x )
dup square-matrix? [ "Matrix must be square." throw ] unless
[ dim first <iota> ] keep
'[ [ _ nth nth ] map-index product ] map-permutations sum ; |
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
... | #Forth | Forth | S" fsl-util.fs" REQUIRED
S" fsl/dynmem.seq" REQUIRED
[UNDEFINED] defines [IF] SYNONYM defines IS [THEN]
S" fsl/structs.seq" REQUIRED
S" fsl/lufact.seq" REQUIRED
S" fsl/dets.seq" REQUIRED
S" permute.fs" REQUIRED
VARIABLE the-mat
: add-perm ( p0 p1 p2 ... pn n s -- )
DROP \ sign
1E
1 DO
the-mat @ SWAP 1- I 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.
| #C.23 | C# | using System;
namespace RosettaCode {
class Program {
static void Main(string[] args) {
int x = 1;
int y = 0;
try {
int z = x / y;
} catch (DivideByZeroException e) {
Console.WriteLine(e);
}
}
}
} |
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.
| #C.2B.2B | C++ |
#include<iostream>
#include<csignal> /* for signal */
#include<cstdlib>
using namespace std;
void fpe_handler(int signal)
{
cerr << "Floating Point Exception: division by zero" << endl;
exit(signal);
}
int main()
{
// Register floating-point exception handler.
signal(SIGFPE, fpe_handler);
... |
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... | #BaCon | BaCon | INPUT "Your string: ", s$
IF REGEX(s$, "^[-+]?[0-9]*\\.?[0-9]+([eE][-+]?[0-9]+)?$") THEN
PRINT "This is a number"
ELSE
PRINT "Not a number"
ENDIF |
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... | #BASIC | BASIC | 10 INPUT "Enter a string";S$:GOSUB 1000
20 IF R THEN PRINT "Is num" ELSE PRINT"Not num"
99 END
1000 T1=VAL(S$):T1$=STR$(T1)
1010 R=T1$=S$ OR T1$=" "+S$
1099 RETURN |
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 ... | #Clojure | Clojure |
(defn uniq-char-string [s]
(let [len (count s)]
(if (= len (count (set s)))
(println (format "All %d chars unique in: '%s'" len s))
(loop [prev-chars #{}
idx 0
chars (vec s)]
(let [c (first chars)]
(if (contains? prev-chars c)
(println (forma... |
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... | #Frink | Frink | collapse[str] := str =~ %s/(.)\1+/$1/g
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/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... | #Go | Go | package main
import "fmt"
// Returns collapsed string, original and new lengths in
// unicode code points (not normalized).
func collapse(s string) (string, int, int) {
r := []rune(s)
le, del := len(r), 0
for i := le - 2; i >= 0; i-- {
if r[i] == r[i+1] {
copy(r[i:], r[i+1:])
... |
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... | #Erlang | Erlang |
-module(string_examples).
-export([examine_all_same/1, all_same_examples/0]).
all_same_characters([], _Offset) ->
all_same;
all_same_characters([_], _Offset) ->
all_same;
all_same_characters([X, X | Rest], Offset) ->
all_same_characters([X | Rest], Offset + 1);
all_same_characters([X, Y | _Rest], Offset... |
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... | #Logtalk | Logtalk | :- category(chopstick).
% chopstick actions (picking up and putting down) are synchronized using a notification
% such that a chopstick can only be handled by a single philosopher at a time:
:- public(pick_up/0).
pick_up :-
threaded_wait(available).
:- public(put_down/0).
put_down ... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #Julia | Julia | using Dates
function discordiandate(year::Integer, month::Integer, day::Integer)
discordianseasons = ["Chaos", "Discord", "Confusion", "Bureaucracy", "The Aftermath"]
holidays = Dict(
"Chaos 5" => "Mungday",
"Chaos 50" => "Chaoflux",
"Discord 5" => "Mojoday",
"Discord 50" => "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... | #Maple | Maple | restart:
with(GraphTheory):
G:=Digraph([a,b,c,d,e,f],{[[a,b],7],[[a,c],9],[[a,f],14],[[b,c],10],[[b,d],15],[[c,d],11],[[c,f],2],[[d,e],6],[[e,f],9]}):
DijkstrasAlgorithm(G,a);
# [[[a], 0], [[a, b], 7], [[a, c], 9], [[a, c, d], 20], [[a, c, d, e], 26], [[a, c, f], 11]] |
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... | #F.C5.8Drmul.C3.A6 | Fōrmulæ | package main
import (
"fmt"
"log"
"strconv"
)
func Sum(i uint64, base int) (sum int) {
b64 := uint64(base)
for ; i > 0; i /= b64 {
sum += int(i % b64)
}
return
}
func DigitalRoot(n uint64, base int) (persistence, root int) {
root = int(n)
for x := n; x >= uint64(base); x = uint64(root) {
root = Sum(x... |
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
... | #Red | Red | Red ["Multiplicative digital root"]
mdr: function [
"Returns a block containing the mdr and persistence of an integer"
n [integer!]
][
persistence: 0
while [n > 10][
product: 1
m: n
while [m > 0][
product: m % 10 * product
m: to-integer m / 10
]
... |
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... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language |
{Baker, Cooper, Fletcher, Miller, Smith};
(Unequal @@ %) && (And @@ (0 < # < 6 & /@ %)) &&
Baker < 5 &&
Cooper > 1 &&
1 < Fletcher < 5 &&
Miller > Cooper &&
Abs[Smith - Fletcher] > 1 &&
Abs[Cooper - Fletcher] > 1 //
Reduce[#, %, Integers] &
|
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 ... | #GLSL | GLSL |
float dot_product = dot(vec3(1, 3, -5), vec3(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... | #Groovy | Groovy | class StringSqueezable {
static void main(String[] args) {
String[] testStrings = [
"",
"\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ",
"..1111111111111111111111111111111111111111111111111111111111111117777888",
"I... |
http://rosettacode.org/wiki/Deming%27s_Funnel | Deming's Funnel | W Edwards Deming was an American statistician and management guru who used physical demonstrations to illuminate his teachings. In one demonstration Deming repeatedly dropped marbles through a funnel at a target, marking where they landed, and observing the resulting pattern. He applied a sequence of "rules" to try to ... | #Haskell | Haskell | import Data.List (mapAccumL, genericLength)
import Text.Printf
funnel :: (Num a) => (a -> a -> a) -> [a] -> [a]
funnel rule = snd . mapAccumL (\x dx -> (rule x dx, x + dx)) 0
mean :: (Fractional a) => [a] -> a
mean xs = sum xs / genericLength xs
stddev :: (Floating a) => [a] -> a
stddev xs = sqrt $ sum [(x-m)**2... |
http://rosettacode.org/wiki/Department_numbers | Department numbers | There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (different from each other) and mu... | #Action.21 | Action! | PROC Main()
BYTE p,s,f
PrintE("P S F")
FOR p=2 TO 6 STEP 2
DO
FOR s=1 TO 7
DO
FOR f=1 TO 7
DO
IF p#s AND p#f AND s#f AND p+s+f=12 THEN
PrintF("%B %B %B%E",p,s,f)
FI
OD
OD
OD
RETURN |
http://rosettacode.org/wiki/Department_numbers | Department numbers | There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (different from each other) and mu... | #Ada | Ada | with Ada.Text_IO;
procedure Department_Numbers is
use Ada.Text_IO;
begin
Put_Line (" P S F");
for Police in 2 .. 6 loop
for Sanitation in 1 .. 7 loop
for Fire in 1 .. 7 loop
if
Police mod 2 = 0 and
Police + Sanitation + Fire = 12 and
... |
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
| #Ring | Ring |
load "stdlibcore.ring"
limit = 1000
row = 0
for n = 1 to limit
flag = 0
strn = string(n)
if isprime(n) = 1
for m = 1 to len(strn)-1
if number(substr(strn,m)) < number(substr(strn,m+1))
flag = 1
ok
next
if flag = 1
row++
see "... |
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
| #Sidef | Sidef | func primes_with_descending_digits(base = 10) {
var list = []
var digits = @(1..^base)
var end_digits = digits.grep { .is_coprime(base) }
list << digits.grep { .is_prime && !.is_coprime(base) }...
for k in (0 .. digits.end) {
digits.combinations(k, {|*a|
var v = a.digits2nu... |
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
| #Wren | Wren | import "./perm" for Powerset
import "./math" for Int
import "./seq" for Lst
import "./fmt" for Fmt
var ps = Powerset.list((9..1).toList)
var descPrimes = ps.skip(1).map { |s| Num.fromString(s.join()) }
.where { |p| Int.isPrime(p) }
.toList
... |
http://rosettacode.org/wiki/Delegates | Delegates | A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See also wp:Delegation pattern.
Objects ... | #Atari_Basic | Atari Basic |
10 REM DELEGATION CODE AND EXAMPLE . ATARI BASIC 2020 A. KRESS andreas.kress@hood-group.com
14 REM
15 GOTO 100:REM MAINLOOP
16 REM
20 REM DELEGATOR OBJECT
21 REM
30 IF DELEGATE THEN GOSUB DELEGATE:GOTO 56
35 REM
50 REM DELEGATOR HAS TO DO THE JOB
55 PRINT "DEFAULT IMPLEMENTATION - DONE BY DELEGATOR"
56 RETURN
60... |
http://rosettacode.org/wiki/Delegates | Delegates | A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See also wp:Delegation pattern.
Objects ... | #C | C | #include <stdio.h>
#include <stdlib.h>
#include <string.h>
typedef const char * (*Responder)( int p1);
typedef struct sDelegate {
Responder operation;
} *Delegate;
/* Delegate class constructor */
Delegate NewDelegate( Responder rspndr )
{
Delegate dl = malloc(sizeof(struct sDelegate));
dl->operation ... |
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)... | #F.23 | F# | open System
type Point = double * double
type Triangle = Point * Point * Point
let Det2D (t:Triangle) =
let (p1, p2, p3) = t
let (p1x, p1y) = p1
let (p2x, p2y) = p2
let (p3x, p3y) = p3
p1x * (p2y - p3y) +
p2x * (p3y - p1y) +
p3x * (p1y - p2y)
let CheckTriWinding allowReversed t =
... |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #ALGOL_68 | ALGOL 68 | main:(
PROC remove = (STRING file name)INT:
BEGIN
FILE actual file;
INT errno = open(actual file, file name, stand back channel);
IF errno NE 0 THEN stop remove FI;
scratch(actual file); # detach the book and burn it #
errno
EXIT
stop remove:
errno
END;
remove("input.txt");
remo... |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #ARM_Assembly | ARM Assembly |
/* ARM assembly Raspberry PI */
/* program deleteFic.s */
/* REMARK 1 : this program use routines in a include file
see task Include a file language arm assembly
for the routine affichageMess conversion10
see at end of this program the instruction include */
/****************************************... |
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
... | #Fortran | Fortran |
!-*- mode: compilation; default-directory: "/tmp/" -*-
!Compilation started at Sat May 18 23:25:42
!
!a=./F && make $a && $a < unixdict.txt
!f95 -Wall -ffree-form F.F -o F
! j example, determinant: 7.00000000
! j example, permanent: 5.00000000
! maxima, determinant: -360.000000
! maxima, perm... |
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.
| #Ceylon | Ceylon | shared void run() {
//integers divided by zero throw an exception
try {
value a = 1 / 0;
} catch (Exception e) {
e.printStackTrace();
}
//floats divided by zero produce infinity
print(1.0 / 0 == infinity then "division by zero!" else "not division by zero!");
} |
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.
| #Clojure | Clojure | (defn safe-/ [x y]
(try (/ x y)
(catch ArithmeticException _
(println "Division by zero caught!")
(cond (> x 0) Double/POSITIVE_INFINITY
(zero? x) Double/NaN
:else Double/NEGATIVE_INFINITY) ))) |
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... | #Batch_File | Batch File | set /a a=%arg%+0 >nul
if %a% == 0 (
if not "%arg%"=="0" (
echo Non Numeric.
) else (
echo Numeric.
)
) else (
echo Numeric.
) |
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... | #BBC_BASIC | BBC BASIC | REPEAT
READ N$
IF FN_isanumber(N$) THEN
PRINT "'" N$ "' is a number"
ELSE
PRINT "'" N$ "' is NOT a number"
ENDIF
UNTIL N$ = "end"
END
DATA "PI", "0123", "-0123", "12.30", "-12.30", "123!", "0"
DATA "0.0", ".123", "-.123", "12E3", "12E-3... |
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 ... | #Common_Lisp | Common Lisp | ;; * Loading the iterate library
(eval-when (:compile-toplevel :load-toplevel)
(ql:quickload '("iterate")))
;; * The package definition
(defpackage :unique-string
(:use :common-lisp :iterate))
(in-package :unique-string)
;; * The test strings
(defparameter test-strings
'("" "." "abcABC" "XYZ ZYX" "1234567890A... |
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... | #Groovy | Groovy | class StringCollapsible {
static void main(String[] args) {
for ( String s : [
"",
"\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ",
"..1111111111111111111111111111111111111111111111111111111111111117777888",
"I neve... |
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... | #F.23 | F# |
// Determine if a string has all the same characters. Nigel Galloway: June 9th., 2020
let fN n=if String.length n=0 then None else n.ToCharArray()|>Array.tryFindIndex(fun g->g<>n.[0])
let allSame n=match fN n with
Some g->printfn "First different character in <<<%s>>> (length %d) is hex %x at positio... |
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... | #Factor | Factor | USING: formatting io kernel math.parser sequences ;
: find-diff ( str -- i elt ) dup ?first [ = not ] curry find ;
: len. ( str -- ) dup length "%u — length %d — " printf ;
: same. ( -- ) "contains all the same character." print ;
: diff. ( -- ) "contains a different character at " write ;
: not-same. ( i elt -- )
... |
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... | #M2000_Interpreter | M2000 Interpreter |
Module Dining_philosophers (whichplan) {
Form 80, 32
Const MayChangePick=Random(True, False)
dim energy(1 to 5)=50
Document Doc$
const nl$={
}
Print $(,12), ' set column width to 12
Pen 14
Pen 15 {
Doc$="Dining Philosophers"+nl$
\\ we can change thread plan only if no threads defined
if whichplan=1 th... |
http://rosettacode.org/wiki/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #Kotlin | Kotlin | import java.util.Calendar
import java.util.GregorianCalendar
enum class Season {
Chaos, Discord, Confusion, Bureaucracy, Aftermath;
companion object { fun from(i: Int) = values()[i / 73] }
}
enum class Weekday {
Sweetmorn, Boomtime, Pungenday, Prickle_Prickle, Setting_Orange;
companion object { fun fr... |
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... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | bd = Graph[{"a" \[DirectedEdge] "b", "a" \[DirectedEdge] "c",
"b" \[DirectedEdge] "c", "b" \[DirectedEdge] "d",
"c" \[DirectedEdge] "d", "d" \[DirectedEdge] "e",
"a" \[DirectedEdge] "f", "c" \[DirectedEdge] "f",
"e" \[DirectedEdge] "f"},
EdgeWeight -> {7, 9, 10, 15, 11, 6, 14, 2, 9},
VertexLabels ... |
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... | #Go | Go | package main
import (
"fmt"
"log"
"strconv"
)
func Sum(i uint64, base int) (sum int) {
b64 := uint64(base)
for ; i > 0; i /= b64 {
sum += int(i % b64)
}
return
}
func DigitalRoot(n uint64, base int) (persistence, root int) {
root = int(n)
for x := n; x >= uint64(base); x = uint64(root) {
root = Sum(x... |
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
... | #REXX | REXX | /*REXX program finds the persistence and multiplicative digital root of some numbers.*/
numeric digits 100 /*increase the number of decimal digits*/
parse arg x /*obtain optional arguments from the CL*/
if x='' | x="," then x=123321 7739 893 899998 ... |
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... | #MiniZinc | MiniZinc |
%Dinesman's multiple-dwelling problem. Nigel Galloway, September 25th., 2020
include "alldifferent.mzn";
enum names={Baker,Cooper,Miller,Smith,Fletcher};
array[names] of var 1..5: res; constraint alldifferent([res[n] | n in names]);
constraint res[Baker] !=5;
constraint res[Cooper] !=1;
constraint res[Fletcher] ... |
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 ... | #Go | Go | package main
import (
"errors"
"fmt"
"log"
)
var (
v1 = []int{1, 3, -5}
v2 = []int{4, -2, -1}
)
func dot(x, y []int) (r int, err error) {
if len(x) != len(y) {
return 0, errors.New("incompatible lengths")
}
for i, xi := range x {
r += xi * y[i]
}
return
}
... |
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... | #Haskell | Haskell | import Text.Printf (printf)
input :: [(String, Char)]
input = [ ("", ' ')
, ("The better the 4-wheel drive, the further you'll be from help when ya get stuck!", 'e')
, ("headmistressship", 's')
, ("\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ", '-')
, ("..... |
http://rosettacode.org/wiki/Deming%27s_Funnel | Deming's Funnel | W Edwards Deming was an American statistician and management guru who used physical demonstrations to illuminate his teachings. In one demonstration Deming repeatedly dropped marbles through a funnel at a target, marking where they landed, and observing the resulting pattern. He applied a sequence of "rules" to try to ... | #J | J |
dx=:".0 :0-.LF
_0.533 0.270 0.859 _0.043 _0.205 _0.127 _0.071 0.275
1.251 _0.231 _0.401 0.269 0.491 0.951 1.150 0.001
_0.382 0.161 0.915 2.080 _2.337 0.034 _0.126 0.014
0.709 0.129 _1.093 _0.483 _1.193 0.020 _0.051 0.047
_0.095 0.695 0.340 _0.182 0.287 0.213 _0.423 _0.021
_0.134 1.798 0.021 _1.099 _0.361 1.636 ... |
http://rosettacode.org/wiki/Department_numbers | Department numbers | There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (different from each other) and mu... | #Aime | Aime | integer p, s, f;
p = 0;
while ((p += 2) <= 7) {
s = 0;
while ((s += 1) <= 7) {
f = 0;
while ((f += 1) <= 7) {
if (p + s + f == 12 && p != s && p != f && s != f) {
o_form(" ~ ~ ~\n", p, s, f);
}
}
}
} |
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
| #XPL0 | XPL0 | include xpllib; \provides IsPrime and Sort
int I, N, Mask, Digit, A(512), Cnt;
[for I:= 0 to 511 do
[N:= 0; Mask:= I; Digit:= 9;
while Mask do
[if Mask&1 then
N:= N*10 + Digit;
Mask:= Mask>>1;
Digit:= Digit-1;
];
A(I):= N;
];
Sort(A, 512);
Cnt:= 0... |
http://rosettacode.org/wiki/Delegates | Delegates | A delegate is a helper object used by another object. The delegator may send the delegate certain messages, and provide a default implementation when there is no delegate or the delegate does not respond to a message. This pattern is heavily used in Cocoa framework on Mac OS X. See also wp:Delegation pattern.
Objects ... | #C.23 | C# | using System;
interface IOperable
{
string Operate();
}
class Inoperable
{
}
class Operable : IOperable
{
public string Operate()
{
return "Delegate implementation.";
}
}
class Delegator : IOperable
{
object Delegate;
public string Operate()
{
var operable = Delegat... |
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)... | #FreeBASIC | FreeBASIC | #macro min(x,y)
Iif(x>y,y,x)
#endmacro
#macro max(x,y)
Iif(x>y,x,y)
#endmacro
type pnt 'typedef for a point
x as double
y as double
end type
type edg 'typedef for an edge
p1 as pnt
p2 as pnt
end type
function point_in_tri( r as pnt, a as pnt, b as pnt, c as pnt ) as boolean
'uses baryc... |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Arturo | Arturo | file: "input.txt"
docs: "docs"
delete file
delete.directory file
delete join.path ["/" file]
delete.directory join.path ["/" docs] |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #AutoHotkey | AutoHotkey | FileDelete, input.txt
FileDelete, \input.txt
FileRemoveDir, docs, 1
FileRemoveDir, \docs, 1 |
Subsets and Splits
Rosetta Code COBOL Python Hard Tasks
Identifies and retrieves challenging tasks that exist in both COBOL and Python, revealing cross-language programming patterns and difficulty levels for comparative analysis.
Rosetta Code Task Comparisons
Identifies tasks common to both COBOL and Python languages that are described as having difficulty levels, revealing cross-language task similarities and providing useful comparative programming examples.
SQL Code Examples from Training Data
Retrieves raw SQL code examples for the SQL language, which is basic data retrieval without meaningful analysis or patterns.
SQL Code Examples from Training Data
Retrieves raw SQL code examples for the SQL language, which is basic filtering that shows what data looks like but doesn't provide meaningful analysis or patterns.
Select Specific Languages Codes
Retrieves specific programming language names and codes from training data, providing basic filtering but limited analytical value beyond identifying these particular languages.