高手近来看看关于 cookie的问题

<?php
setcookie('ggg','aa');
setcookie('ttt','bb');
?>


我的程序里面就只有这两行代码.但是却出现了以下的错误.


Warning: Cannot modify header information - headers already sent by (output started at D:\www_local\PHP\001a.php:2) in D:\www_local\PHP\001a.php on line 4

Warning: Cannot modify header information - headers already sent by (output started at D:\www_local\PHP\001a.php:2) in D:\www_local\PHP\001a.php on line 5

我是想设置两个cookie,却怎么也不能实现.救命啊.

警告：不能修改头信息 - 头已经寄出（开始输出在D：\ www_local \ PHP中\ 001a.php：2）在D：\ www_local \ PHP中\ 001a.php第5行