第八周作业

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。 [必做题]

3.编写一个方法，判断该年份是平年还是闰年。[必做题]

package com.run.test;

import java.util.Scanner;

public class One {
 
    public static void main(String[] args) {
        Scanner b=new Scanner(System.in);
        test a=new test();
        System.out.print("输入数字：");
        int c=b.nextInt();
        int jc=a.jc(c);
        System.out.println(c+"的阶层为"+jc);
        System.out.print("请输入年份：");
        a.pd(b.nextInt());
　　　　　b.close();
    } 
 
}

package com.run.test;

public class test {

    public int jc(int a) {
        int sum=1;
        for (int i = 1; i <=a; i++) {
            sum*=i;
        }
        return sum;
    }
    public void pd(int year) {
        if(year % 4 == 0 && year % 100 != 0 || year % 400 == 0) {
            System.out.println(year + "是闰年！");
     } else {
            System.out.println(year + "不是闰年");
     }
    }
}

1:完善menu注册功能,抽奖,看小故事等功能

package com.run.test;

import java.util.Random;
import java.util.Scanner;

import javax.swing.text.AbstractDocument.BranchElement;

public class Menu {

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

	public static void mainMenu() {
		Scanner input = new Scanner(System.in);
		System.out.println("1.登录");
		System.out.println("2.注册");
		System.out.println("3.幸运抽奖,输入四位会员卡号,如果百位等于系统随机数,就是星运会员.否则不是.");
		System.out.println("4.看小故事,");
		System.out.println("5.退出系统");
		System.out.println("请选择");
		int i = input.nextInt();
		switch (i) {
		case 1:
			login();
			break;
		case 2:
			reg();
			break;
		case 3:
			draw();
			break;
		case 4:
			story();
			break;
		case 5:
			System.out.println("再见");
			break;
		}
	}

	private static void login() {
		Scanner input = new Scanner(System.in);
		System.out.println("输入用户名");
		String uname = input.next();
		System.out.println("输入密码");
		String upwd = input.next();
		if (uname.equals("zs") && upwd.equals("123")) {
			System.out.println("登录成功");
		} else {
			System.out.println("登录失败");
		}
		returnMain();
	
	}
    private static void reg(){
        Scanner input = new Scanner(System.in);
        System.out.println("======注册页面======");
        System.out.println("请输入用户名");
        String uname = input.next();
        System.out.println("输入密码");
        String upwd = input.next();
        System.out.println("======返回登录页面=====");
        login();
    }
	private static void draw() {
		Random r=new Random();
		Scanner input = new Scanner(System.in);
		System.out.print("输入四位会员卡号：");
		int cdnr=input.nextInt();
		int a=cdnr%1000/100;
		int b=r.nextInt(10);
		if (a==b) {
			System.out.println("恭喜中奖");
		} else {
			System.out.println("很遗憾未中奖");
		}
		returnMain();
	}
	private static void story() {
		Scanner input = new Scanner(System.in);
		System.out.println("只有一个故事你莫得选择");
		System.out.println("从前有座山，山上有座庙，庙里有个老和尚给小和尚讲故事");
		System.out.println("继续：1  退出2");
		a:for (;;) {
			int i=input.nextInt();
			switch (i) {
			case 1:
				System.out.println("讲的是");
				break;
			case 2:
				break a;
			}
			System.out.println("从前有座山，山上有座庙，庙里有个老和尚给小和尚讲故事");
		}
		returnMain();
	}
	public static void returnMain(){
		System.out.println("是否返回主菜单?Y/N");
		Scanner input = new Scanner(System.in);
		if (input.next().equalsIgnoreCase("Y")) {
			mainMenu();
		}else{
			System.out.println("谢谢使用");
		}

	}

}