What are some examples of abstract classes in C++?

What are some examples of abstract classes in C++?

Abstract classes in C++ are classes that cannot be instantiated and typically contain at least one pure virtual function. For example, you might have an abstract class called Shape with a pure virtual function draw(). Derived classes like Circle and Square would implement the draw() function.

Can you show me a code example of an abstract class?

Sure! Here's a simple example:

class Shape {
public:
    virtual void draw() = 0; // Pure virtual function
};

class Circle : public Shape {
public:
    void draw() override {
        // Implementation for drawing a circle
    }
};

class Square : public Shape {
public:
    void draw() override {
        // Implementation for drawing a square
    }
};

In this example, Shape is an abstract class, and Circle and Square are concrete classes that implement the draw() method.

What is the purpose of using abstract classes?

Abstract classes allow you to define a common interface for a group of related classes. They enable polymorphism, allowing you to use pointers or references to the abstract class type to refer to objects of derived classes, which can simplify code and enhance flexibility.

Are there any limitations to using abstract classes?

Yes, one limitation is that you cannot create instances of an abstract class directly. Additionally, all derived classes must implement the pure virtual functions, which can lead to more boilerplate code if many derived classes are needed.