Differentiate between function overloading and function overriding

Differentiate between function overloading and function overriding in C++?

Answers


You are putting in place an overloading when you change the original types for the arguments in the signature of a method.

You are putting in place an overriding when you change the original definition of a method.


Overloading a method (or function) in C++ is the ability for functions of the same name to be defined as long as these methods have different signatures (different set of parameters). Method overriding is the ability of the inherited class rewriting the virtual method of the base class.

a) In overloading, there is a relationship between methods available in the same class whereas in overriding, there a is relationship between a superclass method and subclass method.

(b) Overloading does not block inheritance from the superclass whereas overriding blocks inheritance from the superclass.

(c) In overloading, separate methods share the same name whereas in overriding, subclass method replaces the superclass.

(d) Overloading must have different method signatures whereas overriding must have same signature.


Function overloading is done when you want to have the same function with different parameters

void Print(string s);//Print string
void Print(int i);//Print integer

Function overriding is done to give a different meaning to the function in the base class

class Stream//A stream of bytes
{
public virtual void Read();//read bytes
}

class FileStream:Stream//derived class
{
public override void Read();//read bytes from a file
}
class NetworkStream:Stream//derived class
{
public override void Read();//read bytes from a network
}

Overriding means, giving a different definition of an existing function with same parameters, and overloading means adding a different definition of an existing function with different parameters.

Example:

#include <iostream>

class base{
    public:
    //this needs to be virtual to be overridden in derived class
    virtual void show(){std::cout<<"I am base";}
    //this is overloaded function of the previous one
    void show(int x){std::cout<<"\nI am overloaded";} 
};

class derived:public base{
    public:
    //the base version of this function is being overridden
    void show(){std::cout<<"I am derived (overridden)";}
};


int main(){
    base* b;
    derived d;
    b=&d;
    b->show();  //this will call the derived overriden version
    b->show(6); // this will call the base overloaded function
}

Output:

I am derived (overridden)
I am overloaded

1.Function Overloading is when multiple function with same name exist in a class. Function Overriding is when function have same prototype in base class as well as derived class.

2.Function Overloading can occur without inheritance. Function Overriding occurs when one class is inherited from another class.

3.Overloaded functions must differ in either number of parameters or type of parameters should be different. In Overridden function parameters must be same.

For more detail you can visit below link where you get more information about function overloading and overriding in c++ https://googleweblight.com/i?u=https://www.geeksforgeeks.org/function-overloading-vs-function-overriding-in-cpp/&hl=en-IN


Function overloading is same name function but different arguments. Function over riding means same name function and same as arguments


in overloading function with same name having different parameters whereas in overridding function having same name as well as same parameters replace the base class to the derived class (inherited class)


Function overloading - functions with same name, but different number of arguments

Function overriding - concept of inheritance. Functions with same name and same number of arguments. Here the second function is said to have overridden the first


Function overloading may have different return types whereas function overriding must have same or matching return types.


Overloading means having methods with same name but different signature Overriding means rewriting the virtual method of the base class.............


In addition to the existing answers, Overridden functions are in different scopes; whereas overloaded functions are in same scope.


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