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

my @ray = qw(one two three);
my @two = qw(two next four);

foreach my $x (@ray) {
    foreach my $y (@two) {
          print $x if ($x eq $y);
    }   
} 

##</code><code>##

if ($ID=~ m/one.txt two.txt three.txt/)