sub score
{
    my ($x, $y) = @_;

    return $words_equal if $x eq $y;
    return 0 unless $x && $y;

    @{[$x =~ /[$y]/g]};
}

##</code><code>##

sub score
{
    # Same as above, until:
    my $cnt1 = @{[$x =~ /[$y]/g]};
    my $cnt2 = @{[$y =~ /[$x]/g]};

    $cnt1 < $cnt2 ? $cnt1 : $cnt2;
}