#include <iostream.h>

using namespace std;

class BV{             public: virtual void f(){cout <<"BB"; } };
class D1V: public BV{ public: void f(){cout <<"D1"; } };
class D2V: public BV{ public: void f(){cout <<"D2"; } };
main(){
        BV* p;
        p = new D1V; p->f(); p->BV::f();
        p = new D2V; p->f(); p->BV::f();
	cout << endl;
}//end main