JAVA第十周

1.编写一个方法,实现冒泡排序(由小到大),并调用该方法

 

冒泡排序方法

 1     public void sor(int a[]){
 2         int mid=0;
 3         for (int i = 0; i < a.length; i++) {
 4             for (int j = 0; j < a.length-1; j++) {
 5                 if(a[j]>a[j+1]) {
 6                 mid=a[j];
 7                 a[j]=a[j+1];
 8                 a[j+1]=mid;
 9                 }
10             }
11         }
12         System.out.println("\n排序成功");
13     }

 

运行代码

 1 package text;
 2 
 3 public class Run_001 {
 4 
 5     public static void main(String[] args) {
 6         // TODO Auto-generated method stub
 7         int a[]=new int[] {10,20,90,45,83,34,49,76,66,54};
 8         System.out.println("排序前");
 9         for (int i : a) {
10             System.out.print(i+" ");
11         }
12         work10 A=new work10();
13         A.sor(a);
14         for (int i : a) {
15             System.out.print(i+" ");
16         }
17     }
18 
19 }

运行截图


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]

阶乘方法

1     public int Factorials(int n) {
2         int total=1;
3         for (int i = 1; i <= n; i++) {
4             total=total*i;
5         }
6         return total;
7     }

运行

 1 package text;
 2 
 3 public class Run_001 {
 4 
 5     public static void main(String[] args) {
 6         // TODO Auto-generated method stub
 7         work10 A=new work10();
 8         int a=5;
 9         System.out.println(a+"的阶乘"+A.Factorials(a));
10         
11     }
12 
13 }

截图

 


3.编写一个方法,判断该年份是平年还是闰年。[必做题]

年份方法

1     public void year(int y) {
2         if(y%4==0&&y%100!=0||y%400==0) {
3             System.out.println(y+"是闰年");
4         }
5         else {
6             System.out.println(y+"是平年");
7         }
8     }

调用运行

 1 package text;
 2 
 3 import java.util.Scanner;
 4 
 5 public class Run_001 {
 6 
 7     public static void main(String[] args) {
 8         // TODO Auto-generated method stub
 9         work10 A=new work10();
10         Scanner input=new Scanner(System.in);
11         
12         System.out.println("请输入年份");
13         int a=input.nextInt();
14         A.year(a);
15         
16     }
17 
18 }

截图

 

4.课堂没完成的menu菜单,实现幸运抽奖功能

已实现lucky方法功能

 1 package text;
 2 
 3 import java.util.Random;
 4 import java.util.Scanner;
 5 
 6 public class Luckily_Selection {
 7 
 8 
 9         
10         public static void mainMenu(){
11             Scanner input=new Scanner(System.in);
12             System.out.println("欢迎使用本系统");
13             System.out.println("1.登录");
14             System.out.println("2.注册");
15             System.out.println("3.幸运抽奖");
16             System.out.println("4.退出");
17             System.out.println("请选择");
18             int i=input.nextInt();
19             switch(i){
20             case 1:
21                 login();
22                 break;
23             case 2:
24                 reg();
25                 break;
26             case 3:
27                 lucky();
28             }
29             
30             
31         }
32         
33         private static void lucky() {
34             // 输入四位会员卡号,如果百位数等于随机数,幸运会员。否则不是。同时也要询问是否返回主菜单
35             Scanner input=new Scanner(System.in);
36             Random r=new Random();
37             System.out.println("请输入您的四位会员卡号,与幸运数字相同即为中奖");
38             int num=input.nextInt();
39             int h=num/100-num/1000*10;
40             int r1=r.nextInt(9);
41             if(h==r1) {
42                 System.err.println("恭喜你中奖了!");
43             }
44             else {
45                 System.out.println("很遗憾您未能中奖!幸运数字是"+r1);
46             }
47         }
48 
49         public static void returnMain(){
50             Scanner input=new Scanner(System.in);
51             System.out.println("是否返回主菜单?");
52             if(input.next().equalsIgnoreCase("Y"))
53                 mainMenu();
54             else
55                 System.out.println("谢谢使用");
56         }
57         
58         public static void reg() {
59             // TODO Auto-generated method stub
60             Scanner input=new Scanner(System.in);
61             System.out.println("输入要注册的用户名");
62             String uname=input.next();
63             System.out.println("输入注册密码");
64             String upwd=input.next();
65             System.out.println("注册成功");
66             returnMain();
67             
68             
69         }
70 
71 
72         public static void login(){
73             Scanner input=new Scanner(System.in);
74             System.out.println("输入用户名");
75             String uname=input.next();
76             System.out.println("输入密码");
77             String upwd=input.next();
78             if(uname.equals("zs")&&upwd.equals("123")){
79                 System.out.println("ok");
80             }else{
81                 System.out.println("fail");
82             }
83             returnMain();        
84         }
85 
86         
87         public static void main(String[] args) {
88             mainMenu();
89 
90         }
91         
92 
93 
94 }

截图

 

posted @ 2021-05-08 23:06  计算机1903孙铭泽  阅读(49)  评论(0编辑  收藏  举报