#include <iostream>
using namespace std;

struct X {

  X();
  
  virtual void foo() { cout << "foo X" << endl; }
  virtual void bar() { cout << "bar X" << endl; }  
  int x;
};

struct Y : public X {

  Y();
  
  virtual void foo() { cout << "bar Y" << endl; }
  virtual void bar() { cout << "bar Y" << endl; }    

  int y;
};


X::X() { puts("ctor X"); x = 0; }

Y::Y() { perror("ctor Y"); y = 0; }


int x;

int moo(X *px)
{
  px->foo();
  px->bar();
  x = 0;
}

int main()
{
  Y y;
  X *px = &y;
  moo(px);

  cout << "sizeof(X)=" << sizeof(X) << endl;
  cout << "sizeof(Y)=" << sizeof(Y) << endl;  
}