第八周作业

1.完善Menu 注册功能 ,实现所有功能

package method;

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:
            registered();
            break;
        case 3:
            luck();
            break;
        case 4:
            story();
            break;
        case 5:
            outs();
            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();

    }
    
    public static void registered(){
        Scanner input = new Scanner(System.in);
        System.out.println("注册用户名");
        String newname = input.next();
        String n = newname;
        System.out.println("注册密码");
        String newpwd = input.next();
        String p = newpwd;
        if (newname.equals(n) && newpwd.equals(p)) {
            System.out.println("注册成功");
        } else {
            System.out.println("注册失败");
        }
        returnMain();
        
    }
    
    
    public static void luck(){
        Scanner input = new Scanner(System.in);
        Random r = new Random();
        int x = r.nextInt(10);        
        System.out.print("请输入会员编号:");
        int i = input.nextInt();
        System.out.println("系统的百位随机数是" + x);
        if (i < 1000) {
            System.out.println(i + "您的会员编号不合法");
        } else if ((i % 1000 / 100) == x) {
            System.out.println(i + "恭喜您是幸运会员");
        } else {
            System.out.println(i + "很抱歉您不是幸运会员");
        }
        returnMain();
    }

    
    public static void story(){
        System.out.println("1.青蛙王子故事");
        System.out.println("2.白雪公主故事");       
        System.out.println("3.返回主菜单");
        System.out.println("请选择");
        Scanner input = new Scanner(System.in);
        int i = input.nextInt();
        switch (i) {
        case 1:
            System.out.println("很久以前有一位王子........");
            returnMain();
            break;
        case 2:
            System.out.println("很久以前有一位公主........");
            returnMain();
            break;
        case 3: 
            returnMain();
            break;
        }
    }
    
    
    
    public static void outs(){
        
        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。 [必做题]

package method;

public class Jc {

    public static void main(String[] args) {
        
        // TODO Auto-generated method stub
        int sum = getSum(5);
        System.out.println(sum);

    }
    public static int getSum(int num){
        if(num == 1){
            return 1;
        }
        return num*getSum(num-1) ;
        
    }

}

 

3.编写一个方法，判断该年份是平年还是闰年。[必做题]

package method;

import java.util.Scanner;

public class Runnian {

    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.println("请输入年份");
        int a = input.nextInt();
        Text (a);
        
    }
     public static void Text(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");
            }
        }

}