第十周作业

1.编写一个方法，实现冒泡排序（由小到大），并调用该方法

package homework;

import java.util.Arrays;
import java.util.Random;

public class HomeWork2 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub

        int a[]= {
                1,4,3,6,4,7,4,754,
        };
        mp(a);
        for (int i : a) {
            System.out.println(i);
        }
    }
    public static void mp(int a[]) {
        for (int i = 0; i < a.length-1; i++) {
            for (int j = 0; j < a.length-i-1; j++) {
                if(a[j]>a[j+1]) {
                    int temp=0;
                    temp=a[j];
                    a[j]=a[j+1];
                    a[j+1]=temp;
                }
            }
        }
        
    }

}

 

 

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 homework;

import java.util.Arrays;
import java.util.Random;

public class HomeWork2 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub

        int x=3;
        
        int b=mp(x);
        System.out.println(b);
    }
    public static int mp(int n) {
        int a=1;
        for (int i = 1; i < n+1; i++) {
            a=a*i;
        
        }
        return a;
    }

}

 

 

3.编写一个方法，判断该年份是平年还是闰年。[必做题]

package homework;

import java.util.Arrays;
import java.util.Random;
import java.util.Scanner;

public class HomeWork2 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub

        Scanner s = new Scanner(System.in);
        int year = s.nextInt();
        mp(year);
    }
    public static void mp(int year) {
         if(year%4==0 && year%100!=0){
               System.out.print("闰年");
            }else 
            if(year%400==0){
                System.out.print("不是闰年");
            }  
          
         
        
    }

}

 

 

4.课堂没完成的menu菜单，实现幸运抽奖功能