堆排序C++

#include <iostream>
using namespace std;
void MaxHeapify(int *array,int length,int i){
int left=i*2;
int right=i*2+1;
int largest=i;
if(left<=length && array[left]>array[i])
largest=left;
else
largest=i;
if(right<=length && array[right]>array[largest])
largest=right;
if(largest!=i){
int temp=array[largest];
array[largest]=array[i];
array[i]=temp;
MaxHeapify(array,length,largest);
}
}
void BuildMaxHeap(int *array,int length){
for(int i=length/2;i>=1;--i)
MaxHeapify(array,length,i);
}
void HeapSort(int *array,int length){
BuildMaxHeap(array,length);
for(int i=length;i>1;--i){
int temp=array[1];
array[1]=array[i];
array[i]=temp;
MaxHeapify(array,i-1,1);
}
}
int main(){
int n;
cout<<"input number:";cin>>n;
int *array=new int[n+1];
cout<<"input array:";
for(int i=1;i<=n;++i)
cin>>array[i];
HeapSort(array,n);
for(int i=1;i<=n;++i)
cout<<array[i]<<" ";
cout<<endl;
delete[] array;
return 0;
}