断开并转到嵌套开关内的位置

#include "Menu.h"
#include <iostream>
#include <stdio.h>
#include <string>

void Menu::displayMenu() {
    cout << " 1. New User login n 2. View available vehicles n 3. Return Vehicle n 4. Exit Program n";
    char choice;
    cin >> choice;
main:
    switch (choice) {
    case '1': //new user option
        login();
        break;

    case '2': //This will be the option for viewing available cars. each choice in this switch will lead to car info and choice to rent.
    carmenu:
        cout << "Now viewing available vehicles...Select vehicle for further information...n";
        cout << " 1. Toyota Carolla n 2. Toyota Rav4 n 3. Toyota Prius n 4. Ford Mustang n 5. Ford Transit n 6. Main Menu n";
        char rent;
        char carchoice;
        cin >> carchoice;
        switch (carchoice) {
        case '1':
            cout << "Toyota Carolla..n Passenger class n 30 MPG n 4 Doors n";
            cout << "Enter Y to rent vehicle or enter N to return to car selection...n";
            cin >> rent;
            if (rent == 'Y') {
                //construct
            }
            else if (rent == 'N') { goto carmenu; };
        case '2':
            cout << "Toyota Rav4..n Passenger class n 24 MPG n 5 Doors n";
            cout << "Enter Y to rent vehicle or enter N to return to car selection...n";
            cin >> rent;
            if (rent == 'Y') {
                //call passenger car constructor called Rav4 with proper data entries.
            }
            else if (rent == 'N') { goto carmenu; };
            break;
        case '3':
            cout << "Toyota Prius.. n Passenger class n 54 MPG n 4 Doors n";
            cout << "Enter Y to rent vehicle or enter N to return to car selection...n";
            cin >> rent;
            if (rent == 'Y') {
                //call passenger car constructor called Prius with proper data entries.
            }
            else if (rent == 'N') { goto carmenu; };
            break;
        case '4':
            cout << "Ford Mustang.. n Passenger class n 18 MPG n 2 Doors n";
            cout << "Enter Y to rent vehicle or enter N to return to car selection...n";
            cin >> rent;
            if (rent == 'Y') {
                //call passenger car constructor called Mustang with proper data entries.
                break;
            }
            else if (rent == 'N') { goto carmenu; };
            break;
        case '5':
            cout << "Ford Transit ..n Cargo class n 14 MPG n";
            cout << "Enter Y to rent vehicle or enter N to return to car selection...n";
            cin >> rent;
            if (rent == 'Y') {
                Cargo van(14);
                van.set_purpose();
            }
            else if (rent == 'N') { goto carmenu; };
        case '6':
            goto main;

        }//second switch
    }//first switch
}//function end

我希望这不会太难阅读...我正在做一个项目，我必须为一家公司设计一个汽车租赁计划。主菜单的第二种情况将用户带到一个菜单，他可以在其中选择要租用的汽车类型。菜单尚未完全完成，但我已经完成了汽车选择菜单选项 5 的课程。当租车时(在if语句中输入Y(，货物的构造函数被正确调用，但程序要么在输入目的后立即结束，要么返回到汽车租赁页面。我不知道在哪里休息或去发言。谁能帮忙？？