求高手帮忙解答上

求高手帮忙解答下

PHP code

<?php        $baidu = file_get_contents("http://www.baidu.com/s?wd=site:www.baidu.com");        preg_match('/找到相关结果数(.+)个/', $baidu, $baidu_site_num);        print_r($baidu_site_num);?>