#include <iostream>
using namespace std;

class C1 {
public:
	virtual void met(){
		cout << "C1!" << endl;
	}
};

class C2 : virtual public C1{
public:
	void met(){
		cout << "C2!" << endl;
	}
};

class C3 : virtual public C1 {
public:
	void met(){
		cout << "C3!" << endl;
	}
};

// class C4 : public C2, public C3 {};

int main(){
}