Straddling checkerboard: Difference between revisions

<langsyntaxhighlight lang="algol68">#!/usr/local/bin/a68g --script #

)</langsyntaxhighlight>

<langsyntaxhighlight AutoHotkeylang="autohotkey">board := "

MsgBox % dec</langsyntaxhighlight>

<langsyntaxhighlight lang="c">#include <stdio.h>

}</langsyntaxhighlight>

<langsyntaxhighlight Clang="c">#include <stdio.h>

}</langsyntaxhighlight>Output:<syntaxhighlight lang="text">message: In the winter 1965/we were hungry/just barely alive

decoded: INTHEWINTER1965/WEWEREHUNGRY/JUSTBARELYALIVE</langsyntaxhighlight>

=={{header|C sharp|C#}}==

<langsyntaxhighlight lang="csharp">using System;

}</langsyntaxhighlight>

<langsyntaxhighlight lang="cpp">#include <iostream>

};</langsyntaxhighlight>

<langsyntaxhighlight lang="cpp">int main()

}</langsyntaxhighlight>

<langsyntaxhighlight lang="d">import std.stdio, std.algorithm, std.string, std.array;

}</langsyntaxhighlight>

<langsyntaxhighlight lang="d">import std.stdio, std.algorithm, std.ascii;

}</langsyntaxhighlight>

<langsyntaxhighlight lang="d">import std.stdio, std.string, std.algorithm, std.regex, std.array, std.range, std.typecons;

}</langsyntaxhighlight>

<langsyntaxhighlight lang="fsharp">

<langsyntaxhighlight lang="go">package main

}</langsyntaxhighlight>

<langsyntaxhighlight lang="haskell">import Data.Char

, "Decoded: " ++ dec ]</langsyntaxhighlight>

<langsyntaxhighlight Iconlang="icon">procedure main()

end</langsyntaxhighlight>

<langsyntaxhighlight lang="j">'Esc Stop'=: '/.'

)</langsyntaxhighlight>

<langsyntaxhighlight lang="j"> preprocess=: (#~ Charset e.~ ])@toupper NB. verb to compress out non-alphanumerics

ONENIGHTITWASONTHETWENTIETHOFMARCH1888IWASRETURNING</langsyntaxhighlight>

<langsyntaxhighlight lang="j"> preprocess=: Stop&([`([: I. Charset -.@e.~ ])`]} toupper) NB. replace all non-alphanumerics with Stop

ONE.NIGHT.IT.WAS.ON.THE.TWENTIETH.OF.MARCH..1888.I.WAS.RETURNING</langsyntaxhighlight>

<langsyntaxhighlight lang="j">NB. stops setcode alphabet

)</langsyntaxhighlight>

<langsyntaxhighlight lang="j"> 3 7 setcode 'HOLMESRTABCDFGIJKNPQUVWXYZ./'

ONENIGHTITWASONTHETWENTIETHOFMARCH1888IWASRETURNING</langsyntaxhighlight>

<langsyntaxhighlight lang="java">import java.util.HashMap;

}</langsyntaxhighlight>

<langsyntaxhighlight lang="javascript"><script>

</script></langsyntaxhighlight>

<langsyntaxhighlight lang="julia">

<langsyntaxhighlight lang="scala">// version 1.2.0

}</langsyntaxhighlight>

<langsyntaxhighlight lang="lua">

{{trans|Perl 6Raku}}

<langsyntaxhighlight lang="perl">use strict;

my(%transencode,%decode,@table);

while ( my ($k, $v) = each %p2c) {

$trans{encode}{$k} .= $v;

$trans{decode}{$v} .= $k unless $k eq $numeric_escape;

my $keys = join '|', keys %{$trans{decode}};

$string =~ s/($keys)/$trans{decode}{$1}/gr;

$string =~ s#(.)#$trans{encode}{$1} // $trans{encode}{'.'}#ger;

say 'Decoded: ', decode($en);</langsyntaxhighlight>

<span encode[c] style="color: sprintf("%d#008080;",code)>else</span>

-- {encode,decode} = read_table("ETHOL AONMES RISBCDFGHJKLMPQ.UVWXYZRTABCDFGIJKNPQUVWXYZ/.") instead of

-- {encode,decode} = read_table("ETHOL AONMES RISBCDFGHJKLMPQ/UVWXYZRTABCDFGIJKNPQUVWXYZ./"), and

<langsyntaxhighlight lang="php">$key2val = ["A"=>"30", "B"=>"31", "C"=>"32", "D"=>"33", "E"=>"5", "F"=>"34", "G"=>"35",

main('One night-it was on the twentieth of March, 1888-I was returning');</langsyntaxhighlight>

<langsyntaxhighlight PicoLisplang="picolisp">(de *Straddling

(link (if (= "/" C) (pop 'L) C)) ) ) ) ) )</langsyntaxhighlight>

<langsyntaxhighlight lang="purebasic">Procedure.s encrypt_SC(originalText.s, alphabet.s, blank_1, blank_2)

EndIf</langsyntaxhighlight>

<langsyntaxhighlight lang="python">T = [["79", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9"],

print "Decoded:", "".join(unstraddle(straddle(O)))</langsyntaxhighlight>

<langsyntaxhighlight Racketlang="racket">#lang racket

(*straddling (list->vector (list* escape "" header-tail)) main lines))</langsyntaxhighlight>

<langsyntaxhighlight Racketlang="racket">(define (straddling-encode-char char board)

rev-ret)))))</langsyntaxhighlight>

<langsyntaxhighlight Racketlang="racket">(define (test-straddling message board)

"PQ/UVWXYZ."))</langsyntaxhighlight>

:* &nbsp; allow the use of any table &nbsp; (specifiable on the invocation of the &nbsp; '''genCipher''' &nbsp; subroutine, the 5^th line in the REXX program),

:* &nbsp; no hard-coding of the location of blanks,

:* &nbsp; no hard-coding or the numbered lines in the straddled checkerboard table,

:* &nbsp; no hard-coding of the location of the escape character,

:* &nbsp; support the usage of a blank in the 1^st character (the top line of the table).

<langsyntaxhighlight lang="rexx">/*REXX program uses the straddling checkerboard cipher to encrypt/decrypt a message. */

parse arg msg /*obtain optional message from the C.L.*/

enc= encrypt(msg); say ' encrypted=' enc /*encrypt message and show encryption. */

dec= decrypt(enc); say ' decrypted=' dec /*decrypt " " " decryption. */

exit 0 /*stick a fork in it, we're all done. */

genCipher: @.=; arg @..,two,three; z= -1; @.z= @.. /*build top row of cipher.*/

_= pos(' ', @.. ) - 1; @._= two /* " 2nd " " " */

_= pos(' ', @.., _+2) - 1; @._= three /* " 3rd " " " */

do j=0 for 9; @..= @.. || @.j /*construct a table for fast searching.*/

if @.j\=='' then @.r= @.r || j

_= pos('/', @.j) /*is the escape character in this row? */

if _\==0 then @.dig= j || (_-1) /*define " " for numerals.*/

@..= space(@.., 0); return /*purify the table of encryptable chars*/

x= substr(!, j, 1) /*obtain a message char to be encrypted*/

if datatype(x, 'W') then do; $= $ || @.dig || x; iterate; end /*numeral? */

do k=-1 for 10; y= pos(x, @.k) /*traipse thru rows, looking for match.*/

z= k; if z==-1 then z= /*construct the index of the cypher row*/

$= $ || z || (y-1); leave /*add an encrypted character to output.*/

end /*j*/; return $

decrypt: procedure expose @.; parse arg !,,$ /*$: output (decrypted text) so far.*/

do j=1 to length(!); rw= -1 /*process each of the encypted numbers.*/

x= substr(!,j,1) /*obtain a message char to be decrypted*/

if substr(!,j,2)==@.dig then do; j= j+2; $= $ || substr(!, j, 1); iterate; end

if pos(x, @.r)\==0 then do; j= j+1; rw=x; x=substr(!, j, 1); end

$= $ || substr(@.rw, x+1, 1) /*add a character to decrypted message.*/

end /*j*/; return $</syntaxhighlight>

<langsyntaxhighlight lang="ruby">class StraddlingCheckerboard

end</langsyntaxhighlight>

<langsyntaxhighlight lang="ruby">require 'test/unit'

end</langsyntaxhighlight>

Structured as a class, the instances of which contain encoding and decoding mappings suitable for use with Tcl's built in string remapping engine. This uses the fact that no sequence of digits in the encoded form that maps to one character is a prefix of the sequence for any other character. (Inspired by the ''description'' of the [[#Perl 6Raku|Perl 6Raku]] solution.)<!--not a translation though; I didn't read the perl6Raku code…-->

<langsyntaxhighlight lang="tcl">package require Tcl 8.6

}</langsyntaxhighlight>

<langsyntaxhighlight lang="tcl">StraddlingCheckerboardCypher create demo {

puts "Decoded: $output"</langsyntaxhighlight>

<langsyntaxhighlight lang="zkl">var [const]

fcn decode(str){ RegExp("79.|3.|7.|.").pump(str,String,key2val.get) }</langsyntaxhighlight>

<langsyntaxhighlight lang="zkl">txt:="One night-it was on the twentieth of March, 1888-I was returning";

println("Decoded: ", decode(str));</langsyntaxhighlight>