Can you please tell me why one method is better than the other ( code inside!)?

[shahram]

Hi,
Can someone please tell me what is the advantage of method one over method two?

Thanks
Shahram

#include <iostream>
#include "boost/shared_ptr.hpp"



//
// method 1
//
class base{
protected:
  class inner{
  public:
          virtual int f()=0;
  };
  boost::shared_ptr<base::inner> ptr_inner;
  base(boost::shared_ptr<base::inner> new_inner):ptr_inner(new_inner){;};
  public:  
  int f(){return(ptr_inner->f());};
};
class drived:public base{
private:     
         class inner:public base::inner{
                     int f(){return(1);};
         };
public:
         drived(): base(boost::shared_ptr<base::inner>(new drived::inner)){};
};



//
// method 2
//


class base_prime{
public:                 
  virtual int f()=0;
};

class drived_prime:public base_prime{
public:
     int f(){return(1);};               
};





int main(int argc, char *argv[])
{

    base b = drived();
    base_prime b_prime = drived_prime();
    boost::shared_ptr<base_prime> b_prime(new drived_prime());
    std::cout << b.f()<<std::endl;
    std::cout << b_prime->f()<<std::endl;



        return (0);
}