polymorphic_types.hpp

class Animal
{
    public: 
        virtual void makeNoise() const
        {   
            std::cout << "...\n";
        }
        virtual ~Animal() {}
};

class Monkey : public Animal
{
    public: 
        void makeNoise() const override
        {   
            std::cout << "oh oh AH!\n";
        }   
};

class Giraffe : public Animal
{
    public: 
        void makeNoise() const override
        {   
            std::cout << "moooo\n";
        }   
};