第十次作业

.编写一个方法，实现冒泡排序（由小到大），并调用该方法

import java.util.Scanner;
import java.util.Arrays;
import java.util.Random;
public class wang123 {

    /**
     * @param args
     */
     public static void shuzhu() {
            Scanner input = new Scanner(System.in);
            System.out.println("请输入5位数组");
            int x[] = new int[5];
            for (int i = 0; i < x.length; i++) {
                x[i] = input.nextInt();
            }
            for (int i = 0; i < x.length - 1; i++) {
                for (int j = 0; j < x.length - 1; j++) {
                    if (x[j] > x[j + 1]) {
                        int t = x[j];
                        x[j] = x[j + 1];
                        x[j + 1] = t;
                    }
                }
            }
            for (int i : x) {
                System.out.println(i);
            }
        }
    public static void main(String[] args) {
        // TODO Auto-generated method stub
         shuzhu();    
}
}

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.Scanner;
import java.util.Arrays;
import java.util.Random;
public class wang123 {

    /**
     * @param args
     */
     public static void shuzhu(){
         
     }
         public static int jiecheng(int a){
                int sum=1;
                for(int i=1;i<=a;i++){
                    sum*=i;
                }
                return sum;
            }
    public static void main(String[] args) {
        // TODO Auto-generated method stub
          System.out.println(jiecheng(5));
}
}

 

.编写一个方法，判断该年份是平年还是闰年

import java.util.Scanner;
import java.util.Arrays;
import java.util.Random;
public class wang123 {

    /**
     * @param args
     */
     public static void nianfen() {
            Scanner input=new Scanner(System.in);
            int a=input.nextInt();
             if (a % 400 == 0 & a % 100 != 0 | a % 4 == 0)
                 System.out.println("该年为闰年");
             else
                 System.out.println("该年为平年");
         }
        public static void main(String[] args) {
            nianfen();
        }
    
}

课堂没完成的menu菜单，实现幸运抽奖功能

import java.util.Random;

import java.util.Scanner;

public class wang123 {

    /**
     * @param args
     */
    public static void caidan() {
        Scanner input = new Scanner(System.in);
        System.out.println("欢迎使用本系统");
        System.out.println("1.登录");
        System.out.println("2.注册");
        System.out.println("3.幸运抽奖");
        System.out.println("4.退出系统");
        System.out.println("请选择：");
        int i = input.nextInt();
        switch (i) {
        case 1:
            login();
            break;
        case 2:
            register();
            break;
        case 3:
            draw();
            break;
        }
    }
    public static void register(){
        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 pwd=input.next();
        System.out.println("注册成功");
        returnMain();
    }
    public static void returnMain(){
        Scanner input = new Scanner(System.in);
        System.out.println("是否返回主菜单？Y/N");
        if(input.next().equalsIgnoreCase("Y"))
            caidan();
        else
            System.out.println("谢谢使用");
    }

    public 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 pwd=input.next();
        if(uname.equals("1")&&pwd.equals("1"))
            System.out.println("成功");
        else
            System.out.println("失败");
        returnMain();    

    }
    public static void draw(){
        Scanner input = new Scanner(System.in);
        Random r=new Random();
        int a=r.nextInt(10);
        System.out.println("输入四位会员卡号");
        int kahao=input.nextInt();
        int c=kahao%100/10;
        System.out.println("幸运数字为"+a);
        if(c==a){
            System.out.println("是幸运会员");
        }
        else{
            System.out.println("不是幸运会员");
        }
        returnMain();
    }

    public static void main(String[] args) {
        caidan();
    }

}