Sams Teach Yourself C++ in 21 Days , Fifth Edition

Day 14. Polymorphism

On Day 12, “Implementing Inheritance,” you learned how to write virtual functions in derived classes. This is the fundamental building block of polymorphism: the capability to bind specific, derived class objects to base class pointers at runtime.

Today, you will learn

• What multiple inheritance is and how to use it

• What virtual inheritance is and when to use it

• What abstract classes are and when to use them

• What pure virtual functions are

Problems with Single Inheritance

Suppose you’ve been working with your animal classes for a while, and you’ve divided the class hierarchy into Birds and Mammals. The Bird class includes the member function Fly(). The Mammal class has been divided into a number of types of Mammal ...