我的第三行PHP代码之接受安卓端get请求，注册新用户写入数据库

<?php
 $con=mysql_connect("localhost","root","") or die("failed to connect db");
 mysql_select_db("lio")or die ("failed to select db");
 $user=$_GET['user'];
 $passwd=$_GET['passwd'];
 $i="INSERT INTO `userinfo` ( `user` , `passwd` ) VALUES 

('$user','$passwd')";
echo $i;
 mysql_query($i);
?>