Puntero, referencia y virtual

#include <iostream>
#define YO 1
using namespace std;

class A{
    public: virtual int get(){ return YO; }
};
class B : public A{
    public: int get(){ return YO+1; }
};

int main(int argc, char** argv){
    B b;
    A* puntero = &b;
    A &referencia = b;
    cout << b.get() << endl;
    cout << puntero->get() << endl;
    cout << referencia.get() << endl;
    return 0;
}