C++ Abstract Classes Explained

In C++, an abstract class is a class with pure virtual functions that cannot be instantiated and can only be used as a base class. The characteristics and purposes of abstract classes are as follows:

1. Characteristics:

1. Having at least one pure virtual function, which is declared by using “= 0” in the function declaration, pure virtual functions do not have a function body and must be implemented in the derived class.
2. Cannot be instantiated, can only be used as a base class.
3. It can include member variables and non-pure virtual functions.

1. Effect:

1. Provided an interface specification that defines the functionalities that must be implemented by derived classes, thus achieving polymorphism.
2. Inheriting from an abstract class can help avoid repetitive coding, thereby enhancing the reusability and maintainability of the code.
3. Used for categorizing and organizing classes to improve the structure and readability of code.