use bigint;

$num = 3;
$den = 2;
$c = 0;

for ($i = 1; $i <= 1000; $i++) {
    #do our comparisons here
    $c++ if (length($num) > length($den));
    #then find the next number in the series
    $addnum = $den * 2;
    $den += $num;
    $num += $addnum;
}

print "$c\n";