PHP加上字符串類型

Question

我需要使用長整數加上現在我已經創建了這個函數的字符串類型，但它會減慢... 任何人都知道更好的解決方案計算加字符串？

這裏是我的功能：

function math_plus($first, $second) 
{ 
$first = strrev($first); $first_length = strlen($first); 
$second = strrev($second); $second_length = strlen($second); 

$result = ""; 
    if ($first_length > $second_length) 
    { 
    $big = $first; $big_length = $first_length; 
    $small = $second; $small_length = $second_length; 
    } 
    else 
    { 
    $big = $second; $big_length = $second_length; 
    $small = $first; $small_length = $first_length; 
    } 

$memory_exists = false; 
    for ($i=0;$i < $big_length;$i++) 
    { 
    $small_exists = ($i < $small_length)?true:false; 

    $big_value = (int) substr($big, $i, 1); 
    $value = $big_value; 

    if ($small_exists) 
    { 
    $small_value = (int) substr($small, $i, 1); 
    $value += $small_value; 
    } 
    if ($memory_exists){$value++;$memory_exists = false;} 
    if ($value >= 10){$value -= 10; $memory_exists = true;} 

    $result = $value . $result; 
    } 

    if ($memory_exists) 
    { 
    $result = "1" . $result; 
    } 

return $result; 
} 

$first = "325436746798098576787634576587568764355645645654634645746657676543"; 
$second = "325436746798098576787634576587568764355645645654634645746657676543"; 
echo math_plus($first, $second); 

Answer 1

使用bcmath時：http://uk3.php.net/manual/en/function.bcadd.php

bcadd("1.00000", "2.00000");