PHP 计算两个特别大的整数实例代码

function getintadd($a,$b){
$c = '';
$bcount = strlen($b);
$acount = strlen($a);
$count = max($bcount,$acount);
$adiff = $count - $acount;
$bdiff = $count - $bcount;
for($i = $count - 1;$i >= 0;$i--){
$aval = $count - $i <= $acount ? intval($a[$i - $adiff]) : 0;
$bval = $count - $i <= $bcount ? intval($b[$i - $bdiff]) : 0;
$v = $aval + $bval;
if(strlen($c) > 0 && strlen($c) >= $count - $i){
$c = ($v + intval($c[0])).substr($c,1,strlen($c) - 1);
}else{
$c = $v.$c.'';
}
}
return $c;
}
$a = '23490234328490289048902384908392849238';
$b = '234320498324982390489328498230984982399290384902384';
$c = getintadd($a,$b);
print_r($c);