//  A1_1.cpp

#include <iostream>
using namespace std;

class B { 
  
  int x;  // data members needed to show the
          // indexing error, e.g., class objects
          // need to be different sizes

public:
  virtual ~B() {}
  virtual void mf() { cout << "\n  B::mf()"; }
};

class D : public B {

  int y;

  virtual void mf() { cout << "\n  D::mf()"; }
};

void main() {

  {
    B *pB = new D[2];
    pB->mf();
//  (pB+1)->mf();  // this causes an exception
                   // not pointing to beginning 
                   // of second object
  }
  //  memory leak here, pB never deleted
  cout << "\n\n";
}