Constructor Overloading in C++

As we know function overloading is one of the core feature of the object oriented languages. We can use the same name of the functions; whose parameter sets are different. Here we will see how to overload the constructors of C++ classes. The constructor overloading has few important concepts.

Overloaded constructors must have the same name and different number of arguments
The constructor is called based on the number and types of the arguments are passed.
We have to pass the argument while creating objects, otherwise the constructor cannot understand which constructor will be called.

Example

Live Demo

#include <iostream>
using namespace std;

class Rect{
   private:
   int area;
   public:
   Rect(){
      area = 0;
   }
   Rect(int a, int b){
      area = a * b;
   }
   void display(){
      cout << "The area is: " << area << endl;
   }
};

main(){
   Rect r1;
   Rect r2(2, 6);
   r1.display();
   r2.display();
}