堆排序

#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;

const int MAX = 65535;

class HeapSort{
    private:
        int* data;
        int size;
    public:
        //构造函数
        HeapSort(int* data,int len){
            this->size = 0;
            this->data = new int[len+1];
            this->data[0] = MAX;
            for(int i = 0 ; i < len ; i++){
                this->data[++this->size] = data[i];
            }
            this->BuildHeap();
        }

        //把下标为n的子树调整为最大堆
        void Predown(int start ,int end){
            int parent ,child;
            int x = this->data[start];
            for(parent = start ; 2*parent < end ; parent = child){
                child = parent*2;
                //child+1不是最后一个元素，且右孩子大于左孩子 
                if(child+1 != this->size && this->data[child+1] > this->data[child]){
                    child++; 
                }
                if(x >= this->data[child]){
                    break;
                }else{
                    this->data[parent] = this->data[child];
                } 
            }
            this->data[parent] = x;
        } 

        //建堆函数
        void BuildHeap(){
            for(int i = this->size/2 ; i >= 0 ; i--){
                this->Predown(i,this->size);
            }
        }

        void Swap(int* a,int* b){
            *a = *a + *b;
            *b = *a - *b;
            *a = *a - *b; 
        } 

        //堆排序
        void Heap_Sort(){
            for(int i = this->size ; i > 0 ; i--){
                //交换最后一个与第0个元素 
                this->Swap(&this->data[0],&this->data[i]);
                //把0到i-1个数调整为最大堆 
                this->Predown(0,i-1);
            }
        }

        void Print(int start , int end){
            for(int i = start ; i <= end; i++){
                cout<<this->data[i]<<" ";
            }
            cout<<endl;
        } 
};

int main()
{
    cout<<"请输入数组长度:"<<endl;
    int size,*data;
    cin>>size;
    data = new int[size]; 
    srand(time(0));
    cout<<"随机初始化"<<size<<"个数"<<endl;
    for(int i = 0 ; i < size ; i++){
        data[i] = rand()%100+1;
    }

    HeapSort sort(data,size);
    cout<<"堆排序前："<<endl;
    sort.Print(1,size);
    cout<<"堆排序后："<<endl;
    sort.Heap_Sort();
    sort.Print(0,size-1); 

    return 0;
 }