What are abstract classes and how do I override them in C++?

What are abstract classes in C++?

Abstract classes in C++ are classes that cannot be instantiated and are meant to be subclassed. They contain at least one pure virtual function.

Can you explain what a pure virtual function is?

A pure virtual function is a function declared in a base class that has no implementation. It is defined by assigning 0 in its declaration.

How do I override a pure virtual function in a derived class?

To override a pure virtual function, you simply provide an implementation for it in the derived class using the same signature.

Can you give me an example of overriding a function?

Sure! Here's a simple example: if you have a base class Shape with a pure virtual function draw(), you can create a derived class Circle that implements draw().