#include <iostream>
using namespace std;

class A {
	public:
		A() { foo(); }
		virtual void foo() { cout << 1; }
};

class B : public A {
	public:
		B() : A() {
		}
		
		void foo() override { cout << 2; }
};

int main() {
	// your code goes here
	B b;
	return 0;
}