#include <iostream>
 
using namespace std;
 
class A {
	int i;
	
public:
	A (const int j = 0) : i(j) { cout << i << endl;}
	A (const A& a) :i(a.i) { cout << a.i << endl;}
};

class B : public A {

public:
	B(const int j = 0) :A(j) {};
};

int main() {
	B b1 = 20;
	B b2 = b1;
	return 0;
}