#include <iostream>
using namespace std;

class A
{
public:
    static std::string ClassName;
    
    virtual void print() { cout << ClassName << endl; }
};

class B
    : public A
{
};

class C
    : public B
{
};

string A::ClassName = "Klasa A";
string B::ClassName = "Klasa B";
string C::ClassName = "Klasa C";

int main() {
	
	A a;
	B b;
	C c;
	a.print();
	b.print();
	c.print();
	return 0;
}