#!/usr/bin/perl
use strict;
use feature qw{ say };
use warnings;

sub test {
    my ($array1ref, $array2ref) = @_;

    my @array1 = @$array1ref;
    my @array2 = @$array2ref;
    my $count = 0;
    foreach my $element (@array1) {
        foreach my $element2 (@array2) {
            if ($element eq $element2) {
                warn "$element $element2 same";
                $count++;
            } else {
                warn "$element $element2 different";
            }
        }
    }
    return $count
}

my $same = test([qw[ A T C G T C G A G C G ]],
                [qw[ A C G T C C T G T C G ]]);
say "$same matches.";