Polymorphism is the ability to assume many forms. In short it refers to several methods / operators sharing the same name but having different parameter list and different implementations. Variables also can be polymorphic. There are two ways polymorphism can be achieved:

• Polymorphism through scope: For example variables polymorphism.

void F()

{

int cnt 100;

string userResponse;

cin >> userResponse;

if (userResponse 'y')

{

int cnt 50;

cout << cnt << \n ;

}

cout << cnt << \n

}

If a class declares two functions having same name but different parameters it is also polymorphism (in the same scope).

• Polymorphism through inheritance:
• Overloading: Say class Shape has a function CalcArea(int int). Say a class Circle() is derived from Shape. It overloads the CalcArea() method by specifying only one int parameter radius.
• Overriding: Continuing the same example suppose a class rectangle is derived from Shape. It overrides the method CalcArea(int int) to provide its implementation. Class Triangle also overrides the method and provides its implementation.
• A derived class declares a data member having same name as the base class data member.