#ifndef HeapSort_hpp
#define HeapSort_hpp

#include <stdio.h>
#include <vector>

using namespace std;

class HeapSort {
    
    
public:
    void sort(vector<int>& arr, int len) {
        //1、構件大頂堆
        for(int i = len/2 - 1;i >= 0; i--) {
            //從第一個非葉子節點，從下至上，從右至左調整結構
            adjustHeap(arr, i, len);
        }
        //2、調整堆結構，交換堆頂元素與末尾元素
        for(int j = len-1; j > 0; j--) {
            //交換堆頂元素和尾元素
            swap(arr, 0, j);
            //重新對堆進行調整
            adjustHeap(arr, 0, j);
        }
    }
    
    void adjustHeap(vector<int>& arr, int i, int len) {
        int temp = arr[i];//暫存當前待調整元素
        //從i節點的左子節點開始，也就是2i+1處開始
        for (int k = 2*i+1; k < len; k = k*2+1) {
            //如果左子節點小於右子節點，k指向右子節點
            if (k + 1 < len && arr[k] < arr[k+1]) {
                k++;
            }
            //如果子節點大於父節點，將子節點賦值給父節點
            if (arr[k] > temp) {
                arr[i] = arr[k];
                i = k;
            }else {
                break;
            }
        }
        arr[i] = temp;//將temp值放到最終位置
    }
    
    
    void swap(vector<int>& arr, int aIndex, int bIndex) {
        int temp = arr[aIndex];
        arr[aIndex] = arr[bIndex];
        arr[bIndex] = temp;
    }
};


#endif /* HeapSort_hpp */

/*HeapSort.hpp*/

#include "HeapSort.hpp"

/*mian.cpp*/
#include "HeapSort.hpp"
#include <iostream>
#include <vector>
using namespace std;
int main(int argc, const char * argv[]) {
    vector<int> arr7 = {7, 5, 3, 2, 4, 9, 1, 8, 0, 6};
    cout << "arr7: " << endl;
    for (int item : arr7) {
        cout << item <<" ";
    }
    cout << endl;
    HeapSort heapSort = HeapSort();
    heapSort.sort(arr7, int(arr7.size()));
    cout << "heap sort arr7: " << endl;
       for (int item : arr7) {
           cout << item <<" ";
       }
       cout << endl;
    return 0;
}