// Illustration of an ambiguity problem when we
// deal with a replicated base class.

#include <iostream>
#include <string>

using namespace std;

class A {
public:
  int a;
  A(int a): a(a){}
};

class B : public A {
public:
  int b;
  B(): b(1), A(5) {}
};

class C : public A {
public:
  int c;
  C(): c(2), A(7){}
};

class D : public B, public C {
public:
  int d;
  D(): d(9){}    // use default constructors of B and C
};


int f(D &x){
  cout << x.a << endl;     // error: request for member  a  is ambiguous
  cout << x.B::a << endl;  // 5
  cout << x.C::a << endl;  // 7
  cout << x.b << endl;     // 1 
  cout << x.c << endl;     // 2
  cout << x.d << endl;     // 9

}

int main(){
  D d;
  f(d);
}