Eight sorts ------------- heap sort

Heap sort ：

1. Build the big top heap

How to build a large top pile First, traverse the query for each value of the array to see if there is a corresponding child node , Then determine whether the left child node is larger than the right child node , If it is less than , Let the left child node ++, Then exchange the child node and the parent node to traverse , In the end =0, Then let its child node be the parent node , The child node of a child is the child node , Compared with children when changing nodes laugh , In this way, a lot of roofs are built

2. Swap the top element with the last value , then length-1 Continue to traverse upward to determine a maximum value each time .

public static void main(String[] args) {
        int[] arr = new int[]{5,7,4,2,0,3,1,6};
        for (int p = arr.length-1;p>=0;p--){
            adjust(arr,p,arr.length);
        }
        // Top and bottom elements are interchanged
        for(int i = arr.length-1;i>=0;i--){
            int temp = arr[0];
            arr[0] = arr[i];
            arr[i] = temp;
            adjust(arr,0,i);
        }
        System.out.println(Arrays.toString(arr));
    }

    public static void adjust(int[] arr,int parent,int length) {
        int Child = 2 * parent + 1;
     while(Child<length) {
         int rChild = Child+1;
                 if(rChild<length && arr[rChild]>arr[Child]) {
                     Child++;
                 }
                 if(arr[parent]<arr[Child]) {
                     int temp = arr[Child];
                     arr[Child] = arr[parent];
                     arr[parent] = temp;
                     parent = Child;
                   Child = 2 * Child + 1;
              }else {
                  break;
              }
                 }
     }