Types of Inheritance in C++

Types of Inheritance in C++: As we have already learned regarding inheritance in the previous articles. Let us learn about the different types of inheritances present in C++.

Types of Inheritance in C++

• Single Inheritance
• Multiple Inheritance
• Hierarchical Inheritance
• Multilevel Inheritance
• Hybrid Inheritance

Single Inheritance

The single inheritance can be used in such a way that one derived class inherits from only one base class. And it is also known as the simplest form of inheritance.

Syntax:

class subclass_name : access_mode base_class
{
//body of subclass
};

Example:

#include<iostream> 
using namespace std; 
  
//base class 
class Vehicle { 
  public: 
    Vehicle() 
    { 
      cout<<"This is a Vehicle"<<endl; 
    } 
}; 
  
//subclass derived from two 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; 
}

Output:

This is a Vehicle

Multiple Inheritance

The multiple inheritances a single derived class may inherit from two or more base classes.

Syntax:

class A
{
……….
};
class B
{
………..
} ;
class C: acess_specifier A,access_specifier A // derived class from A and B
{
………..
} ;

Example:

#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; 
    } 
}; 
//subclass 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; 
}

Output:

This is a Vehicle
This is a 4 wheeler Vehicle

Hierarchical Inheritance

The hierarchical inheritance can be used to derive more than one subclass is inherited from a single base class.

Syntax:

class A // base class
{
…………..
};
class B: access_specifier A // derived class from A
{
………..
} ;
class C: access_specifier A // derived class from A
{
………..
} ;
class D: access_specifier A // derived a class from A
{
………..
} ;

Example:

#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; 
}

Output:

This is a Vehicle
This is a Vehicle

Multilevel Inheritance

The multi-level inheritance can be used if the derived class is obtained from another derived class.

 

Example:

#include<iostream> 
using namespace std; 
  
// base class 
class Vehicle  
{ 
  public: 
    Vehicle() 
    { 
      cout << "This is a Vehicle" << endl; 
    } 
}; 
class fourWheeler: public Vehicle 
{  public: 
    fourWheeler() 
    { 
      cout<<"Objects with 4 wheels are vehicles"<<endl; 
    } 
}; 
// sub class derived from two base classes 
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; 
}

Output:

This is a Vehicle
Objects with 4 wheels are vehicles
The car has 4 Wheels

Hybrid (virtual) Inheritance

The hybrid inheritance can be used for combining more than one type of inheritance.

Example: Combining   hierarchical and multiple inheritances

#include <iostream> 
using namespace std;  
//base class  
class Vehicle  
{ 
  public: 
    Vehicle() 
    { 
      cout<<"This is a Vehicle" << endl; 
    } 
}; 
  
//base class 
class Fare 
{ 
    public: 
    Fare() 
    { 
        cout<<"Fare of Vehicle\n"; 
    } 
}; 
  
// first sub class  
class Car: public Vehicle 
{ 
  
}; 
  
// second sub class 
class Bus: public Vehicle, public Fare 
{ 
      
}; 
// main function 
int main() 
{    
    // creating object of sub class will 
    // invoke the constructor of base class 
    Bus obj2; 
    return 0; 
}