#!/usr/bin/perl

use strict;
use warnings;
use LWP::Simple;
use HTML::SimpleLinkExtor;

die "Usage: $0 URL <extension> [<extenstions>]\n" unless @ARGV >= 2;

my $url=shift;
my $wanted=join '|', map quotemeta, @ARGV;
$wanted=qr/\.(?:$wanted)$/;

defined(my $html=get $url) or die "Couldn't get <$url>\n";

{
    local $,="\n";
    print sort grep /$wanted/,
      HTML::SimpleLinkExtor->new->parse($html)->a;
}

__END__