新人求助= =

#include<iostream>
using namespace std;
class Vector
{
public:
Vector(int s=100){buffer=new int[size=s];};
int &Elem(int index)
{
return buffer[index];
}
void Display( )
{ for(int j=0; j<size; j++)
cout<<Elem(j)<<" ";
cout<<endl;
}
void Set( )
{for(int j=0; j<size; j++)
Elem(j)=(j+1)*(j+1);
}
~Vector( ){delete[] buffer;}
protected:
int size;
int *buffer;
};
int main()
{
Vector a(10);
a.Set();
a.Display();
cout<<a.Elem(1)<<endl;
cout<<a.Elem (a.Elem(1))<<endl;}