第八周作业

package hhhhkj;
import java.util.Random;

import java.util.Scanner;

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:
            zhuce();
            break;
        case 3:
            choujiang();
            break;
        case 4:
            story();
            break;
        case 5:
        	tuichu();
            break;

    }
}



private static void story() {
    System.out.println("故事");
    System.out.println("故事讲完了");
    returnMain();
}

private static void choujiang() {
    Random r=new Random();
    int i1 = r.nextInt(10);
    System.out.println("请您输入你的卡号");
    Scanner input = new Scanner(System.in);
    int i = input.nextInt();
    if (i1==i%1000/100){
        System.out.println("哈哈哈你中奖了");
    }else {
        System.out.println("呜呜呜你没有中奖");
    }
    returnMain();

}

private static void login() {
    // TODO Auto-generated method stub
    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();

}
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");
    }

}
public static void zhuce(){
    System.out.println("请输入用户名");
    Scanner input = new Scanner(System.in);
    String line = input.nextLine();
    System.out.println("请输入密码");
    int i = input.nextInt();
    login();

}
public static void tuichu(){
	System.out.println("------------------------------------");
	System.out.println("你已退出");
}

　　2.

 

package hhhhkj;

import java.util.Scanner;

public class kjklkjkj {

	public static void main(String[] args) {
		jc();
    }
    public static void jc(){
        Scanner input =new Scanner(System.in);
        int i,sum=1;
        System.out.println("请输入一个整数");
        int n=input.nextInt();
        for( i=1;i<=n;i++){
            sum*=i;
            }
        System.out.println("阶乘为 "+sum);
        }
 
}
	
		

　　3

package hhhhkj;

import java.util.Scanner;

public class kjklkjkj {

	public static void main(String[] args) {
		System.out.println("是不是闰年");
		
	        year();
	    }
	    public static void year(){
	        Scanner input =new Scanner(System.in);
	        int sum=1;
	        System.out.println("请输入年份");
	        int x=input.nextInt();
	        if(x%4==0){
	            System.out.println("是闰年"+x);
	        }
	        else{
	            System.out.println("是平年"+x);
	        }
	        }
	     
	}