"better" solution for OO birds problem

birds_style.cpp

#include <iostream>
#include <cassert>

class FlyStyle
{
  public:
    virtual void Fly() const = 0;
};

class FlyHigh : public FlyStyle
{
  virtual void Fly() const
  {
    std::cout << "Fly high!" << std::endl;
  }
};

class NoFly : public FlyStyle
{
  virtual void Fly() const
  {
    std::cout << "No fly!" << std::endl;
  }
};

class SpeakStyle
{
  public:
    virtual void Speak() const = 0;
};

class SpeakLoud : public SpeakStyle
{
  virtual void Speak() const
  {
    std::cout << "Speak LAUD!!!!" << std::endl;
  }
};

class NoSpeak : public SpeakStyle
{
  virtual void Speak() const
  {
    std::cout << "No speaking!" << std::endl;
  }
};

class SuperBird
{
  public:
    SuperBird(FlyStyle* fly, SpeakStyle* speak)
      : flystyle(fly),
      speakstyle(speak)
  {
    assert(NULL != flystyle);
    assert(NULL != speakstyle);
  }

    ~SuperBird() { delete flystyle; delete speakstyle;}

    virtual void Fly() const
    {
      flystyle->Fly();
    }
    virtual void Speak() const
    {
      speakstyle->Speak();
    }
  protected:
    FlyStyle* flystyle;
    SpeakStyle* speakstyle;
};

class SuperBirdFactory
{
  public:
    static SuperBird* createEagle()
    {
      return new SuperBird(new FlyHigh(), new SpeakLoud()); 
    }
    static SuperBird* createPenguin()
    {
      return new SuperBird(new NoFly(), new NoSpeak()); 
    }
};

int main()
{
  SuperBird* bird = NULL;

  bird = SuperBirdFactory::createEagle();
  bird->Fly();
  bird->Speak();
  delete bird; bird = NULL;

  bird = SuperBirdFactory::createPenguin();
  bird->Fly();
  bird->Speak();
  delete bird; bird = NULL;

  return 0;
}