Swift3 Swift 3：准备segue获取至少三个场景的视图控制

我需要得到第五个场景后，我点击登录使用 覆盖功能准备（对于segue:UIStoryboardSegue，发送方：有吗？）

已解决

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        let next : UITabBarController = segue.destination as! UITabBarController

        let next1 : TopTabBarController = next.viewControllers![0] as! TopTabBarController

        let next2 : UINavigationController = next1.viewControllers![0] as! UINavigationController

        let next3 : VehicleTableViewController = next2.topViewController as! VehicleTableViewController

        next3.userid = "abcdefghijklmn";
    }