Polymorphism

Polymorphism means "many forms", and it occurs when we have many classes that are related to each other by inheritance.

Like we specified in the previous chapter;
Inheritance lets us inherit attributes and methods from another class.
Polymorphism uses those methods to perform different tasks.
This allows us to perform a single action in different ways.

For example, think of a base class called Animal that has a method called animalSound().
Derived classes of Animals could be Pigs, Cats, Dogs, Birds -
And they also have their own implementation of an animal sound
(the pig oinks, and the cat meows, etc.)

Example:-
// Base class class Animal { public: void animalSound() { cout << "The animal makes a sound \n" ; } }; // Derived class class Pig : public Animal { public: void animalSound() { cout << "The pig says: wee wee \n" ; } }; // Derived class class Dog : public Animal { public: void animalSound() { cout << "The dog says: bow wow \n" ; } };

Now we can create Pig and Dog objects and override the animalSound() method

// Base class class Animal { public: void animalSound() { cout << "The animal makes a sound \n" ; } }; // Derived class class Pig : public Animal { public: void animalSound() { cout << "The pig says: wee wee \n" ; } }; // Derived class class Dog : public Animal { public: void animalSound() { cout << "The dog says: bow wow \n" ; } }; int main() { Animal myAnimal; Pig myPig; Dog myDog; myAnimal.animalSound(); myPig.animalSound(); myDog.animalSound(); return 0; }

Why And When To Use "Polymorphism?
Same as Inheritance - - It is useful for code reusability: reuse attributes and methods of an existing class when you create a new class.