Basically this is a technique I want to share. In this specific case it was useful for me to find the complete path of some files of which for some reson I knew only basenames.

Please note that I'm not proposing this as a general purpose technique for in that case it would be less efficient than a simpler approach. It is specifically thought to be more efficient when successive entries have a high probability of matching the same condition.

Basically this is the same technique described in my post available at "Just wanted to share this technique..." on clpmisc. So see also the thread that followed it for some discussions on the topic (including repeated misunderstandments!!)

UPDATE: due to subsequent discussions and implied experimenting, (see in particular Re^4: Yet Another...), I changed the original snippet to the current one. For reference the original snippet posted here is available at original snippet.

#!/usr/bin/perl -li.bak

use strict;
use warnings;

my @pre=map "../../pics/$_/", '00'..'16';

while (<>) {
    chomp;
    my $cnt;
    for my $p (@pre) {
        local $_ = $p . $_;
        if (-e) {
            print;
            @pre[0..$cnt] = @pre[$cnt,0..$cnt-1] if $cnt;
            last;
        }
        $cnt++;
    }
} 

__END__
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