if ($user==""||$pwd==""||$pwd_confirm==""){
echo "<script>alert('Please confirm the integrity of the information ');history.go(-1);</script>";
}
elseif ($code!=$_SESSION["ver_code"] ){
echo "<script>alert('Verification code is incorrect');history.go(-1);</script>";
}
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
Please check the instructions for using the logical operation "||"