算法笔记 --- Heap Sort

#include <iostream>

using namespace std;

class HeapSort {
public:
    int* heapSort(int* A, int n) {

        buildMaxHeap(A, n);
        int tmp;
        for(int i = n-1; i >0; i--){
            tmp = A[0];
            A[0] = A[i];
            A[i] = tmp;
            adjustMaxHeap(A, 0, i);
        }
        return A;
    }
    void adjustMaxHeap(int* A, int index_node, int size){
        int var_max = index_node;
        int left_child = index_node*2+1;
        int right_child = index_node*2+2;
        int tmp;
        // cout<<"left_child: "<<left_child<<endl;
        // cout<<"right_child: "<<right_child<<endl;
        // cout<<"var_max: "<<var_max<<endl;
        if(A[left_child] > A[var_max] && left_child < size){
            var_max = left_child;
        }
        if(A[right_child] > A[var_max] && right_child < size){
            var_max = right_child;
        }
        if(var_max != index_node){
            tmp = A[index_node];
            A[index_node] = A[var_max];
            A[var_max] = tmp;
            
            adjustMaxHeap(A, var_max, size);
        }
    }
    void buildMaxHeap(int* A, int size){
        for(int i = (size/2-1); i >= 0; i--){
            // cout<<"i: "<<i<<endl;
            adjustMaxHeap(A, i, size);
        }
    }
};

int main()
{
   int a[6] = {1,5,2,3,2,3};
   HeapSort sorter;
   int* res = sorter.heapSort(a, 6);
   cout<<"result: "<<endl;
  for(int i = 0; i < 6; i++){
      cout<<res[i]<<" ";
  }
  cout<<endl;
   return 0;
}