reference member from multiple base classes

NBases, same member

#include <iostream>

class Base1 {
 public:
  int index;
  Base1() : index(1) {};
};

class Base2 {
 public:
  int index;
  Base2() : index(2) {};
};

class Derived : public Base1, public Base2 {};

int main () {

  Derived d;

  std::cout << d.Base1::index << std::endl;
  std::cout << d.Base2::index << std::endl;

  return 0;
}