switch处理多分支结构

import java.util.Scanner;

/**
 * Created by liwenj on 2017/7/17.
 */
public class test9 {
    public static void main(String[] args) {
        Scanner input=new Scanner(System.in);
        System.out.println("1.登录系统");
        System.out.println("2.退出系统");
        System.out.print("请输入数字：");
        int check=input.nextInt();
       switch (check){
           case 1:
               System.out.println("主菜单");
               System.out.println("1.客户信息管理");
               System.out.println("2.购物结算");
               System.out.println("3.回馈");
               System.out.println("4.退出");
               System.out.println("请输入数字");
               int op=input.nextInt();
               switch (op){
                   case 1:
                       System.out.println("1.添加客户信息");
                       System.out.println("2.修改客户信息");
                       break;
                   case 2:
                       System.out.println("1.幸运抽奖");
                       System.out.println("2.生日问候");
               }
               break;
           case 2:
               System.exit(1);//退出程序
       }

    }

}