PHP Manual: Subtract numbers

GMP gmp_sub(GMPintstring $num1, GMPintstring $num2)

Subtracts num2 from num1 and returns the result.

num1

The number being subtracted from.

A GMP object, an int or a numeric string.

num2

The number subtracted from num1.

A GMP object, an int or a numeric string.

A GMP object.

Example #1 gmp_sub example

<?php
$sub = gmp_sub("281474976710656", "4294967296"); // 2^48 - 2^32
echo gmp_strval($sub) . "\n";
?>

The above example will output:

281470681743360