#include <iostream.h>

class unAnimal
{
public:
  virtual void s_exprimer() const = 0;
};

class unMamifere
: public unAnimal
{};

class unChat
: public unMamifere
{
public:
  void s_exprimer() const { cout << "Miaou" << endl; };
};

class uneSouris
: public unMamifere
{
public:
  void s_exprimer() const { cout << "Couic" << endl; };
};

class unOiseau
: public unAnimal
{};

class unCanari
: public unOiseau
{
public:
  void s_exprimer() const { cout << "Cuicui" << endl; };
};