Types of Inheritance in Object-Oriented Programming

Inheritance is a key concept in Object-Oriented Programming (OOP) that allows one class (child or derived class) to inherit attributes and methods from another class (parent or base class). This promotes code reusability and establishes a relationship between classes.

Types of Inheritance

1. Single Inheritance: A child class inherits from one parent class.
2. Multiple Inheritance: A child class inherits from multiple parent classes.
3. Multilevel Inheritance: A child class inherits from a parent class, which in turn inherits from another parent class.
4. Hierarchical Inheritance: Multiple child classes inherit from a single parent class.
5. Hybrid Inheritance: A combination of two or more types of inheritance.

1. Single Inheritance

In single inheritance, a class inherits from one parent class.

class Animal {
public:
    void sound() {
        cout << "Animal makes a sound" << endl;
    }
};

class Dog : public Animal {
public:
    void bark() {
        cout << "Dog barks" << endl;
    }
};

2. Multiple Inheritance

In multiple inheritance, a class inherits from more than one parent class. (Note: Not supported directly in Java, but can be achieved through interfaces.)

class Flyer {
public:
    void fly() {
        cout << "Flying" << endl;
    }
};

class Swimmer {
public:
    void swim() {
        cout << "Swimming" << endl;
    }
};

class Duck : public Flyer, public Swimmer {
};

3. Multilevel Inheritance

In multilevel inheritance, a class inherits from a parent class, which is also a derived class of another parent class.

class Animal {
public:
    void eat() {
        cout << "Eating" << endl;
    }
};

class Dog : public Animal {
public:
    void bark() {
        cout << "Barking" << endl;
    }
};

class Puppy : public Dog {
public:
    void weep() {
        cout << "Weeping" << endl;
    }
};

4. Hierarchical Inheritance

In hierarchical inheritance, multiple child classes inherit from a single parent class.

class Animal {
public:
    void eat() {
        cout << "Eating" << endl;
    }
};

class Dog : public Animal {
public:
    void bark() {
        cout << "Barking" << endl;
    }
};

class Cat : public Animal {
public:
    void meow() {
        cout << "Meowing" << endl;
    }
};