堆排序程序之一

#include<iostream>
#include <cmath>
#include<vector>

using namespace std;

template <class T>
void max_heap(T* heap, int i) //heap[0]存储堆的大小
{
    int l=2*i;   //l为左孩子的结点编号
    int r=2*i+1; //r为右孩子的结点编号
    int largest=i;
    int heap_size=heap[0];
    T temp;
    if(l<=heap_size && heap[l]>heap[i])
        largest=l;
    if(r<=heap_size && heap[r]>heap[largest])
        largest=r;
    if(largest != i){
        temp = heap[i];
        heap[i] = heap[largest];
        heap[largest] = temp;
        max_heap(heap, largest);
    }        
}

template <class T>
void build_max_heap(T* heap)
{
    int heap_size=heap[0];
    for (int i=floor(heap_size/2); i>=1; --i)
        max_heap(heap,i);
}

template <class T>
void heap_sort(T* heap)
{
    T temp;
    int heap_size=heap[0];
    build_max_heap(heap);
    for (int i=heap_size; i>=2; --i)
    {
        temp=heap[1];
        heap[1]=heap[i];
        heap[i]=temp;
        heap[0]--;
        max_heap(heap,1);
    }
}

int main()
{
    int a[10]={9,8,2,7,6,5,3,4,9,0};
    //vector<int> a(9,8);
    //int a[10]={8,0,8,7,6,5,3,4,2,9};
    //max_heap(a,1);
    //build_max_heap(a);
    heap_sort(a);
    for (int i=1; i<=9; i++)
        cout<<a[i]<<' ';
    cout<<endl;
    return 0;
}