第八周作业2

1、完善menu注册功能,抽奖,看小故事等功能
import java.util.Scanner;
import java.util.Random;

public class TEXT1 {
    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");
        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:
            logon();
            break;
        case 3:
             lottery ();
             break;
        case 4:
            story();
            break;
        case 5:
            exist();
            break;
        }
    }

    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("Sphinxman") && upwd.equals("123")) {
            System.out.println("登录成功");
        } else {
            System.out.println("登录失败");
        }
        returnMain();
    }

    private static void logon() {
        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();
        System.out.println("恭喜，注册成功!");
        returnMain();
    }
    
    private static void lottery(){
        Scanner input =new Scanner(System.in);
        System.out.println("输入四位会员卡号");
        int x=input.nextInt();
        Random a= new Random();
        int y = a.nextInt();
        if(x==y/100*10){
            System.out.println("恭喜，你被抽为幸运用户");
        }else{
            System.out.println("谢谢参与");
        }
        returnMain();
    }
    
     private static void story() {
            Scanner input = new Scanner(System.in);
            System.out.println("选择故事：");
            System.out.println("1、小红帽");
            System.out.println("2、农夫与蛇");
            System.out.println("3、人生哲理");
            int a = input.nextInt();
            switch (a) {
            case 1:
                System.out.println("从前有一个小女孩一直戴着一个红色的小帽子，"
                        + "大家都叫她小红帽......");
                break;
            case 2:
                System.out.println("有一位心地善良的农夫走在路上，突然发现一只被冻僵的蛇躺在路边，于是他......");
                break;
            case 3:
                System.out.println("每一篇文章都是一泓甜美的清泉，浇灌每一位读者的心田"
                        + "\n"+ "每一条人生哲理都是一道营养的美味，滋补每一位读者的灵魂");
                break;
            }
            returnMain();
     }
     
     public static void exist(){
         System.out.println("谢谢使用");
     }
     
    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");
        }

    }

}

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。
import java.util.*;

public class Text3 {
    
    
    public static double jc(int a){
        int x=1;
        for(int i=1;i<=a;i++){
            x*=i;
        }
        return x;
    }
    public static void main(String[] args) {
        Scanner input= new Scanner(System.in);
        System.out.println("请输入数字：");
        int i=input.nextInt();
        System.out.println("阶乘等于："+jc(i));
    }
}

3、编写一个方法，判断该年份是平年还是闰年。
import java.util.*;

public class Text5 {
    public static void 年份(int year) {
        if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0) {
            System.out.println(year + "年"+"\n"+"该年是闰年");
        } else {
            System.out.println(year + "年"+"\n"+"该年不是闰年");
        }
    }
    public static void main(String[] args) {
        Scanner input=new Scanner(System.in);
        System.out.println("输入年份：");
        int a=input.nextInt();
        年份(a);
    }
}