冒泡排序（待理解）

1.原理： 

2.代码实现：

package com.example.suanfademo.sort;

public class Bubble {
    
    public static void sort(Comparable[] a){
        for (int i=a.length-1;i>0;i--){
            for (int j=0;j0;
    }

    
    private static void exch(Comparable[] a,int i,int j){
        Comparable temp;
        temp = a[i];
        a[i] = a[j];
        a[j] = temp;

    }
}

package com.example.suanfademo.Test;

import com.example.suanfademo.sort.Bubble;

import java.util.Arrays;

public class BubbleTest {
    public static void main(String[] args) {
        Integer[] arr = {4,5,6,3,2,1};
        Bubble.sort(arr);
        System.out.println(Arrays.toString(arr));
    }
}

3.冒泡排序最坏情况下：时间复杂度为O(N^2)

所以冒泡排序适合于待排元素较少的情况