session_start();
$t = time();//当前时间
$changeTime = 300;// 时间间隔，单位：秒
$mima = '202406';//初始
if(isset($_SESSION['time'])){
	if(($t - $_SESSION['time']) >= $changeTime){
		$_SESSION['time'] = $t;$mima = mt_rand(99999, 999999);$_SESSION['rand'] = $mima;
		}else{
			$mima = $_SESSION['rand'];
			}
           }else{
            $_SESSION['time'] = $t;$mima = mt_rand(0, 9999);$_SESSION['rand'] = $mima;
            }
echo $mima;