Paste code

//Add in Appdelegate Class 

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        // Override point for customization after application launch.
        
         let storyboard = UIStoryboard(name: "Main", bundle: nil)
        let mainViewController = storyboard.instantiateViewController(withIdentifier: "Main") as! MainViewController
        let leftViewController = storyboard.instantiateViewController(withIdentifier: "Left") as! LeftViewController
        
        let slideMenuController = SlideMenuController(mainViewController: mainViewController, leftMenuViewController: leftViewController, rightMenuViewController: leftViewController)
        self.window?.rootViewController = slideMenuController
        self.window?.makeKeyAndVisible()
        
        
        return true
    }