4.24 第八周作业

1.完善menu的注册功能，抽奖以及讲小故事等功能。

  1 package text;
  2 
  3 import java.util.Scanner;
  4 import java.util.Random;
  5 
  6 public class Menu {
  7 
  8     public static void main(String[] args) {
  9         // TODO Auto-generated method stub
 10         mainMenu();
 11     }
 12 
 13     public static void mainMenu() {
 14         Scanner input = new Scanner(System.in);
 15         System.out.println("1.登录");
 16         System.out.println("2.注册");
 17         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
 18         System.out.println("4.看小故事");
 19         System.out.println("5.退出系统");
 20         System.out.println("请选择");
 21         int i = input.nextInt();
 22         switch (i) {
 23         case 1:
 24             login();
 25             break;
 26         case 2:
 27             register();
 28             break;
 29         case 3:
 30             raffle();
 31             break;
 32         case 4:
 33             story();
 34             break;
 35         case 5:
 36             exit();
 37             break;
 38 
 39         }
 40     }
 41 
 42     private static void login() {
 43         // TODO Auto-generated method stub
 44         Scanner input = new Scanner(System.in);
 45         System.out.println("输入用户名");
 46         String uname = input.next();
 47         System.out.println("输入密码");
 48         String upwd = input.next();
 49         if (uname.equals("zs") && upwd.equals("123")) {
 50             System.out.println("登录成功");
 51         } else {
 52             System.out.println("登录失败");
 53         }
 54         returnMain();
 55 
 56     }
 57 
 58     private static void register() {
 59         // TODO Auto-generated method stub
 60         Scanner input = new Scanner(System.in);
 61         System.out.println("设置用户名");
 62         String uname = input.next();
 63         System.out.println("设置密码");
 64         String upwd = input.next();
 65         if (uname.equals(null) || upwd.equals(null)) {
 66             System.out.println("注册成功");
 67         } else {
 68             System.out.println("注册失败");
 69         }
 70         returnMain();
 71 
 72     }
 73 
 74     // 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
 75     private static void raffle() {
 76         // TODO Auto-generated method stub
 77         Scanner input = new Scanner(System.in);
 78         System.out.println("输入四位会员卡号:");
 79         int kahao = input.nextInt();
 80         Random r = new Random();
 81         int suiji = r.nextInt(10);
 82         if (kahao / 100 % 10 == suiji) {
 83             System.out.println("恭喜您是幸运会员！");
 84         } else {
 85             System.out.println("您不是幸运会员");
 86         }
 87         returnMain();
 88     }
 89 
 90     public static void story() {
 91         System.out.println("三只小猪");
 92         returnMain();
 93     }
 94 
 95     public static void exit() {
 96         System.out.println("是否退出系统Y/N");
 97         Scanner input = new Scanner(System.in);
 98         String a = input.next();
 99         if (a.equalsIgnoreCase("y")) {
100             System.out.println("退出系统成功");
101         } else {
102             returnMain();
103         }
104     }
105 
106     public static void returnMain() {
107         System.out.println("是否返回主菜单?Y/N");
108         Scanner input = new Scanner(System.in);
109         if (input.next().equalsIgnoreCase("Y")) {
110             mainMenu();
111         } else {
112             System.out.println("谢谢使用");
113         }
114     }
115 }

2.编写一个方法，求整数n的阶乘，例如5的阶乘是5*4*3*2*1.

 1 package text;
 2 
 3 import java.util.Scanner;
 4 
 5 public class JieCheng {
 6 
 7     public static void main(String[] args) {
 8         // TODO Auto-generated method stub
 9         jc();
10     }
11 
12     public static void jc() {
13         Scanner input = new Scanner(System.in);
14         int mul = 1;
15         System.out.println("输入一个数:");
16         int a = input.nextInt();
17         for (int i = 1; i <= a; i++) {
18             mul *= i;
19         }
20         System.out.println(a + "的阶乘为:" + mul);
21     }
22 
23 }

3.编写一个方法，判断该年份是平年还是闰年。[必做题]

 1 package text;
 2 
 3 import java.util.Scanner;
 4 
 5 public class JieCheng {
 6 
 7     public static void main(String[] args) {
 8         // TODO Auto-generated method stub
 9         nianfen();
10     }
11 
12     public static void nianfen() {
13         Scanner input = new Scanner(System.in);
14         System.out.println("输入一个年数:");
15         int year = input.nextInt();
16         if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0) {
17             System.out.println("该年份为闰年");
18         } else {
19             System.out.println("该年份为平年");
20         }
21     }
22 }