#include
using namespace std;
class Base {
public:
virtual void who(void) {
cout << "Base\n";
}
};
class first_d : public Base {
public:
void who(void) {
cout << "First derivation\n";
}
};
class second_d : public Base {
// who() not defined
};
main(void)
{
Base base_obj;
Base *p;
first_d first_obj;
second_d second_obj;
p = &base_obj;
p->who();
p = &first_obj;
p->who();
p = &second_obj;
p->who();
return 0;
}