Vigenère cipher: Difference between revisions

=={{header|Arturo}}==

<lang rebol>Letters: append `A`..`Z` `a`..`z`

encrypt: function [msg, key][

pos: 0

result: new ""

loop msg 'c ->

if in? c Letters [

'result ++ to :char (((to :integer key\[pos]) + to :integer upper c) % 26) + to :integer `A`

pos: (pos + 1) % size key

]

return result

]

decrypt: function [msg, key][

pos: 0

result: new ""

loop msg 'c [

'result ++ to :char ((26 + (to :integer c) - to :integer key\[pos]) % 26) + to :integer `A`

pos: (pos + 1) % size key

]

return result

]

text: "Beware the Jabberwock, my son! The jaws that bite, the claws that catch!"

key: "VIGENERECIPHER"

encr: encrypt text key

decr: decrypt encr key

print text

print encr

print decr</lang>

{{out}}

<pre>Beware the Jabberwock, my son! The jaws that bite, the claws that catch!

WMCEEIKLGRPIFVMEUGXQPWQVIOIAVEYXUEKFKBTALVXTGAFXYEVKPAGY

BEWARETHEJABBERWOCKMYSONTHEJAWSTHATBITETHECLAWSTHATCATCH</pre>