第八周作业

package lianxi;
import java.util.Random;
import java.util.Scanner;

public class Menu {

    
    public static void main(String[] args) {
        mainMenu();
    }

    public static void mainMenu() {
        Scanner sc = new Scanner(System.in);
        System.out.println("1.登录");
        System.out.println("2.注册");
        System.out.println("3.幸运抽奖");
        System.out.println("4.看小故事");
        System.out.println("5.退出系统");
        System.out.println("请选择");
        int i = sc.nextInt();
        switch (i) {
        case 1:
            login();
            break;
        case 2:
            zhuce();
            break;
        case 3:
            choujiang();
            break;
        case 4:
            read();
            break;
        case 5:
            exit();
            break;
        }
    }

    private static void login() {
        // TODO Auto-generated method stub
        Scanner sc = new Scanner(System.in);
        System.out.println("输入用户名");
        String uname = sc.next();
        System.out.println("输入密码");
        String upwd = sc.next();
        if (uname.equals("tzy") && upwd.equals("816")) {
            System.out.println("登录成功");
        } else {
            System.out.println("登录失败");
        }
        returnMain();
    }
    
    private static void zhuce() {
        Scanner zc = new Scanner(System.in);
        System.out.println("输入用户名：");
        String name = zc.next("tzy");
        System.out.println("输入密码");
        String psw = zc.next("816");
        System.out.println("注册成功！");
        returnMain();
    }
    
    private static void choujiang() {
        Scanner hy = new Scanner(System.in);
        System.out.print("请输入四位会员号：");
        Random sj = new Random();
        int sjs = sj.nextInt();
        int hynum = hy.nextInt();
        if(hynum/100%10==sjs) {
            System.out.println("您是星选会员！");
        }else {
            System.out.println("您不是星选会员！");
        }
        returnMain();
    }
    
    private static void read() {
        System.out.println("请选择故事：");
        System.out.println("1.丑小鸭");
        System.out.println("2.卖火柴的小女孩");
        Scanner rd = new Scanner(System.in);
        int gs = rd.nextInt();
        switch(gs) {
        case 1:
            System.out.println("您选择的是丑小鸭");
            break;
        case 2:
            System.out.println("您选择的是卖火柴的小女孩");
            break;
        default:
            System.out.println("重新选择。");
            read();
        }returnMain();
    }
    
    private static void exit() {
        System.out.println("欢迎下次使用！再见！");
    }
    
    public static void returnMain(){
        System.out.println("是否返回主菜单?Y/N");
        Scanner sc = new Scanner(System.in);
        if (sc.next().equalsIgnoreCase("Y")) {
            mainMenu();
        }else{
            System.out.println("谢谢使用");
        }

    }

}

package com.xuexiao;

import java.util.Scanner;


public class jc {
/*2.编写一个方法，求整数n的阶乘，例如5的阶乘是1*2*3*4*5。*/
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        
        jcmain();
    }
    private static void jcmain() {
        Scanner sc = new Scanner(System.in);
        System.out.print("请输入一个数：");
        int sj = sc.nextInt();
        int sum=1;
        for(int i =sj ;i>=1;i--) {
            sum*=i;
        }System.out.println(sum);
    }
}

package com.xuexiao;

import java.util.Scanner;

public class near {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
/*3．.编写一个方法，判断该年份是平年还是闰年*/
        near();
    }
    private static void near() {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入一个年份：");
        int nf = sc.nextInt();
        if(nf %400 ==0 ||(nf %4==0&& nf%100!=0)) {
            System.out.println("闰年");
        }else {
            System.out.println("平年");
        }
    }

}