If you ever need to use this, please see http://php.net/manual/en/function.gmp-fact.php
示例 #1 Factorial function using GMP
<?php
function 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.
If you ever need to use this, please see http://php.net/manual/en/function.gmp-fact.php