DEFINITION 9: INHERITANCE - PRATMG/2143-OOP-Tamang GitHub Wiki

Inheritance is a concept that describes a class's capacity to derive features and traits from another class. One of the most crucial aspects of Object Oriented Programming is inheritance.

Sub Class: The class that inherits properties from another class is called Sub class or Derived Class.
Super Class:The class whose properties are inherited by sub class is called Base Class or Super class.

inheritance

Types of Inheritance in C++:

Single Inheritance:

In single inheritance, one sub class is inherited by one base class only. single-inheritance

// C++ program to explain
// Single inheritance
#include <iostream>
using namespace std;

// base class
class Vehicle {
public:
	Vehicle()
	{
	cout << "This is a Vehicle" << endl;
	}
};

// sub class derived from a single base classes
class Car: public Vehicle{

};

// main function
int main()
{
	// creating object of sub class will
	// invoke the constructor of base classes
	Car obj;
	return 0;
}

Multiple Inheritance:

Multiple Inheritance is a C++ feature that allows a class to inherit from multiple classes at the same time. i.e. a subclass can be inherited from multiple base classes.

multiple-inheritance

// C++ program to explain
// multiple inheritance
#include <iostream>
using namespace std;

// first base class
class Vehicle {
public:
	Vehicle()
	{
	cout << "This is a Vehicle" << endl;
	}
};

// second base class
class FourWheeler {
public:
	FourWheeler()
	{
	cout << "This is a 4 wheeler Vehicle" << endl;
	}
};

// sub class derived from two base classes
class Car: public Vehicle, public FourWheeler {

};

// main function
int main()
{
	// creating object of sub class will
	// invoke the constructor of base classes
	Car obj;
	return 0;
}

Multilevel Inheritance:

In this type of inheritance, a derived class is created from another derived class.

multilevel-inheritance

// C++ program to implement
// Multilevel Inheritance
#include <iostream>
using namespace std;

// base class
class Vehicle
{
public:
	Vehicle()
	{
	cout << "This is a Vehicle" << endl;
	}
};

// first sub_class derived from class vehicle
class fourWheeler: public Vehicle
{ public:
	fourWheeler()
	{
	cout<<"Objects with 4 wheels are vehicles"<<endl;
	}
};
// sub class derived from the derived base class fourWheeler
class Car: public fourWheeler{
public:
	Car()
	{
	cout<<"Car has 4 Wheels"<<endl;
	}
};

// main function
int main()
{
	//creating object of sub class will
	//invoke the constructor of base classes
	Car obj;
	return 0;
}

Hierarchical Inheritance:

In this type of inheritance, more than one derived class is created from a single base class. hierarchical-inheritance

// C++ program to implement
// Hierarchical Inheritance
#include <iostream>
using namespace std;

// base class
class Vehicle
{
public:
	Vehicle()
	{
	cout << "This is a Vehicle" << endl;
	}
};


// first sub class
class Car: public Vehicle
{

};

// second sub class
class Bus: public Vehicle
{
	
};

// main function
int main()
{
	// creating object of sub class will
	// invoke the constructor of base class
	Car obj1;
	Bus obj2;
	return 0;
}