Php/docs/gmp.examples

From Get docs

Examples

Example #1 Factorial function using GMP

<?phpfunction fact($x) {    $return = 1;    for ($i=2; $i <= $x; $i++) {        $return = gmp_mul($return, $i);    }    return $return;}echo gmp_strval(fact(1000)) . "\n";?>

This will calculate factorial of 1000 (pretty big number) very fast.