#!/usr/bin/perl -w
use strict;

##</code><code>##

use warnings;

##</code><code>##

opendir(THISDIR,"e:\\perl\\comics\\");
my @comics=readdir(THISDIR);
close(THISDIR);

##</code><code>##

my @comics=glob 'e:/perl/comics/*';
# or 'e:/perl/comics/*.png', according to your description

##</code><code>##

foreach (reverse(@comics)) {

##</code><code>##

   my ($name,$ext)=split(/\./,$_);

##</code><code>##

ls -1 *.png | perl -lne '$o=$_; s/(\d+)/sprintf "%03d", $1/e; rename $o, $_'