Function Overloading and Overriding in C++

What is Function Overriding?

In the case of inheritance, when the base class and the derived class have a function with the name, then the function of the derived class overrides the function of the base class, known as function overriding. Function overriding is achieved during runtime. It is a form of runtime polymorphism.

Function Overriding is the redefinition of the base class function in its derived class with the same return type and parameters. 

For example

Class Base_calss
{
    public: 
    virtual void print()
    {
        cout<<"Coding"<<endl;
    }
};
Class Derived_class:public Base_class
{
    public:
    void print()
    { 
        cout<<"Coding Ninjas"<<endl;
    }
};

Also see, Literals in C.

Program to Illustrate Function Overloading in C++

Code

• C++

C++

#include<bits/stdc++.h>
using namespace std;
int addition(int x,int y)
{
    return x+y;
}
int addition(int x,int y,int z)
{
    return x+y+z;
}
double addition(double x,double y)
{
    return x+y;
}
int main()
{
  int a=10, b=5, c=12;
  double p=5.25, q=15.92;
  cout<<"The value of a+b+c="<<addition(a,b,c)<<endl;
  cout<<"The value of a+b="<<addition(a,b)<<endl;
  cout<<"The value of p+q="<<addition(p,q);
  return 0;
}

You can also try this code with Online C++ Compiler

Run Code

Output

The value of a+b+c=27
The value of a+b=15
The value of p+q=21.17

In the above code, We overload the addition() function. Based on the number and type of arguments passed during the function call, the corresponding addition() function is called.

Program to Illustrate Function Overriding in C++

Code

• C++

C++

#include<bits/stdc++.h>
using namespace std;
class Base_class
{
    public:
    virtual void print()
    {
        cout<<"This is print() function of Base_calss"<<endl;
    }
    void show()
    {
        cout<<"This is show() function of Base_class"<<endl;
    }
};
class Derived_class:public Base_class
{
    public:
    void print()
    {
        cout<<"This is print() function of Derived_class"<<endl;
    }
};
// Driver code
int main()
{
    Derived_class dc;
    Base_class &bc=dc;
    bc.print();
    dc.show();
    dc.print();
}

You can also try this code with Online C++ Compiler

Run Code

Output

This is print() function of Derived_class
This is show() function of Base_class
This is print() function of Derived_class

Try and compile with online c++ compiler.

In the above code, The same function print() is defined in both the Base_class and Derived_class. When we call the function print() from the Derived_class object, "dc", and the base_class object,  "bc", the print() from the Derived_class is invoked and executed by overriding the same function of the Base_class. When we call show() function from the Derived_class object, "dc", the show() function from the Base_class is executed. 

Difference between Function Overloading and Overriding in C++

Frequently asked questions

What is overloading and overriding in C++?

Function overloading in C++ allows multiple functions in the same scope with the same name but different parameters. Overriding, on the other hand, occurs in inheritance when a derived class redefines a base class member function.

What is operator overriding in C++?

Operator overriding in C++ enables operators like +, -, *, etc., to be redefined for user-defined types. This allows custom behavior when using these operators with objects of a class.

What is the difference between overriding and polymorphism in C++?

Overriding involves redefining a base class function in a derived class, while polymorphism refers to the ability of a single function name to have multiple implementations based on the object it is called upon. Overriding is a specific aspect of achieving polymorphism in C++.

Conclusion

In this blog, we learned about Function Overloading and Function Overriding. This blog also covers the difference between function overloading and function overriding.

To study more about Function Overloading, refer to this

Recommended Readings:

• Multiple Inheritance in Java
• CPP Abstract Class
• Yarn vs NPM

This blog is over, but learning never stops, and there is a lot more to learn. Have a nice day and Happy Coding!