#!/usr/bin/perl -w

use strict;

my @array1 = qw[a b c d e];
my @array2 = qw[a n o t h e r];

my %count;
foreach my $element (@array1, @array2) {
  $count{$element} += 1;
}
foreach my $key (keys %count) {
  print "$key appears in both arrays\n" if $count{$key} == 2;
}