实现用户注册、登录、幸运抽奖功能，验证次数最多3次

package work20191122;

import java.util.Scanner;

public class Project {

	public static void main(String[] args) {
		
		Scanner input = new Scanner(System.in);
					
		int n;
		String user;
		String password;
		String u;
		String p;
		
		while(true) {
			System.out.println("****欢迎进入奖客富翁系统******");
			System.out.println("\t1.注册");
			System.out.println("\t2.登录");
			System.out.println("\t3.抽奖");
			System.out.println("*****************************");
			
			System.out.print("请选择菜单：");
			n= input.nextInt();
			
			switch(n) {
			case 1:
					System.out.println("[奖客富翁系统 > 注册]");
					System.out.println("请填写个人注册信息：");
					System.out.print("用户名：");
				    user = input.next();
					System.out.print("密码：");
					password = input.next();
					
					int max = 9999;
					int min = 1000;
					int cardNumber = (int)(Math.random()*(max-min)) +min;

					System.out.println();
					System.out.println("注册成功，请记好您的会员卡号");
					System.out.println("用户名\t密码\t会员卡号");
					System.out.println(user+"\t"+password+"\t"+cardNumber);
					
					System.out.print("继续吗?(y/n):");
					String n1 = input.next();
					switch(n1) {
					case "y":
						continue;
					case "n":
						break;
					}
					break;
			case 2:
				System.out.println("[奖客富翁系统 > 登录]");
				
				int x=3;
				do {
					System.out.print("请输入用户名：");
					u = input.next();
					System.out.print("请输入密码：");
					p = input.next();
					if(u.equals("admin") && p.equals("123456")) {
						System.out.println("欢迎您："+u);
						break;
					}else {
						System.out.println("输入错误！您还有"+(--x)+"次机会！\n");
					}
					
					}while(x>0);
					if(x==0) {
					System.out.println("对不起！您3次均输入错误！");
				}
		
				System.out.print("继续吗?(y/n):");
				String n2 = input.next();
				switch(n2) {
				case "y":
					continue;
				case "n":
					break;
				}
				break;
			case 3:
				System.out.println("[奖客富翁系统 >抽奖]");
				System.out.print("请输入您的卡号：");
				int card = input.nextInt();
				
				int max1 = 9999;
				int min1 = 1000;
				int cardNumber1 = (int)(Math.random()*(max1-min1)) +min1;
				int cardNumber2 = (int)(Math.random()*(max1-min1)) +min1;
				int cardNumber3 = (int)(Math.random()*(max1-min1)) +min1;
				int cardNumber4 = (int)(Math.random()*(max1-min1)) +min1;
				int cardNumber5 = (int)(Math.random()*(max1-min1)) +min1;
				
				System.out.println();
				System.out.println("本月的幸运数字为："+cardNumber1+"\t"+cardNumber2+"\t"+cardNumber3+"\t"+cardNumber4+"\t"+cardNumber5);
				
				if(card==cardNumber1||card==cardNumber2||card==cardNumber3||card==cardNumber4||card==cardNumber5) {
					System.out.println("恭喜！您是本月的幸运会员！");
				}else {
					System.out.println("抱歉！您不是本月的幸运会员！");
				}
				
				System.out.print("继续吗?(y/n):");
				String n3 = input.next();
				switch(n3) {
				case "y":
					continue;
				case "n":
					break;
				}
				break;
			default:
				System.out.println("您的输入有误！");
				break;
			}
			break;
		}
		System.out.println();
		System.out.println("系统退出，谢谢使用！");
		
		
	}

}