#!/usr/bin/perl

$ ..=$ _ for qw|$ @=/b..u\;/_@ =vqv \?qvcl+FOTO ,_@:_$;kbv($_@ =$ @;jd/_;++\(d
qR_"/2. ._;\(vz xH$ _@,xHjdy$ _@)) )$ @;$. =kbv[$ _@] ,_0= ~{}w {g|;$ _=$ . ,y
,/FO\\{vzlu}\$dqR_Hjk\@yq(xybRc),(DA)/punz\\\@for\$him_to{stare},,s.. $ _.gee;
print map { map { $ %= 0 ;s '([A-Z])(?{$ %=1})'lc$ 1'e ;$ ;=$ .[ $ *] [ - 97 +
ord ]; $ *+= $ *== @ .-1? -$ *:1 ;ord> 96?$ %? uc$ ; :$ ; :$ _ }split//}<DATA>


__DATA__
The Vigenere cipher, known by some as 'le chiffre indechiffrable' (French for
'the indecipherable cipher') is a method of encryption that uses a series of
different Caesar ciphers based on the letters of a keyword, though there is
some argument among cryptographic circles as to which incarnation of this
particular polyalphabetic substitution can accurately be attributed to Blaise
de Vigenere.  This implementation is a simple form of a polyalphabetic
substitution.  To encipher, a table of alphabets can be used, termed a tabula
recta, or Vigenere table.  It consists of the alphabet written out 26 times
in different rows, each alphabet shifted cyclicly to the left compared to the
previous alphabet.  Incidentally, there's a good chance that this plaintext
is long enough to display the cryptographical weakness of this particular
algorithm.  Can you spot it?