sidef/scripts/vigenere_cipher.sf

#!/usr/bin/ruby

func s2v(s) { s.uc.scan(/[A-Z]/)»ord»() »-» 65 };
func v2s(v) { (v »%» 26 »+» 65)»chr»() -> join };

func blacken (red, key) { v2s(s2v(red) »+« s2v(key)) };
func redden  (blk, key) { v2s(s2v(blk) »-« s2v(key)) };

var red = "Beware the Jabberwock, my son! The jaws that bite, the claws that catch!";
var key = "Vigenere Cipher!!!";

say red;
say (var black = blacken(red, key));
say redden(black, key);