#include <iostream>
#include <cstdlib>
using namespace std;

class base {
protected:
	void f() const {cout << "base::f\n";}
};

class derived1: public base {
};

class derived2: public base {
public:
	void g() const {
		f();           //will compile
		derived2 d2;
		d2.f();        //will compile

		derived1 d1;
		//d1.f();      //won't compile
		base b;
		//b.f();       //won't compile
		//static_cast<const base *>(this)->f();   //won't compile
	}
};

int main()
{
	derived2 d2;
	d2.g();
	return EXIT_SUCCESS;
}