#include <iostream>
struct A { A(){std::cout << "A, ";} };
struct B { B(){std::cout << "B, ";} };
struct X: virtual public A, private B { X(){std::cout << "X, ";} };
struct Y: virtual public A, private B { Y(){std::cout << "Y, ";} };
struct Z : public Y, public X { Z(){std::cout << "Z, ";} };

int main() { Z test; }