sub p_idiomatic
{
    # Use a numeric sort to enforce that m is greater then n
    my ($m, $n) = sort { $b <=> $a } $_[0], $_[1];

    # This is the same as:
    # my ($m, $n) = reverse sort { $a <=> $b } $_[0], $_[1];

    # Holds the remainder
    my $r;

    # Insure that they are positive integers
    # Is their a better way to do this?
    if (($m < 1) || ($n < 1)) {
        die("Values must be positive integers.");
    }
    do {{
        $r = $m % $n;
        $m = $n;
        $n = $r;
    }} until $r == 0;

    return $m;
}