More Dirty Things to do in Perl: Unsorting
Traduction: [ Google | Babelfish ]
Catégories : [ Informatique ]
I discussed today with Matthieu Fritz about how the act of reading was
processed in the brain, and he reminded me of a chain e-mail containing text
where the letters of the words were scrambled, except the first one and the
last one, and which was still surprisingly readable. He wondered if it worked
with any text, or if the text in the e-mail was carefully composed. I quickly
hacked a Perl script doing the job, and in the middle of writing it, I was
wondering how I could scramble the letters of a word without writing too much
code. The the solution popped into my mind: use sort, unsing rand instead of
a comparison function. Here's the resulting script:
sub scramble {
my $s = shift @_;
my @letters = split //,$s;
my $first = shift @letters;
# Do not scramble words starting with an uppercase letter
return $s if $first =˜ /[A-Z]/;
my $last = pop @letters;
my $rand = int(rand(2));
# $rand == 0 means that the letters won't be exchanged, but we want as much
# scrambling as possible, therefore we discard the use of 0
$rand = -1 if $rand == 0;
my @l = sort { $rand } @letters;
return "$first".join("", @l)."$last";
}
while (<>) {
# Scramble the words composed of lowercase letters and accentuated
# characters
s/([a-z\xa0-\xff]+)/&scramble($1)/ge;
print;
}
Verdict: it works with short and common words, but not with longer or rarers ones.
[ Posté le 1er octobre 2007 à 20:39 | pas de commentaire | lien permanent ]
