Constructor Overloading in C++

October 28, 2021

C++ Constructor Overloading

Constructor Overloading is similar to Function Overloading, we can define more than one constructors for a class. The following are necessary conditions for the same –

Name of constructor should be same as the name of the class
The parameters passed in each variation of constructor should be different example –
- Demo(int x) and Demo(int x, int y)
Constructors are basically special functions of the class itself.

We recommend reading our post on Constructors here first.

Implementation for Constructor Overloading

#include <iostream>
using namespace std;
class Demo
{
  int x, y;
  public:
    Demo()
    {
       x = 0;
       y = 0;
    }
    Demo(int x1, int y1)
    {
      x = x1;
      y = y1;
    }
    Demo(int x1)
    {
     x = x1;
     y = x1;
    }

    void print()
    {
    cout<<"\nValues are : "<<x<<" and "<<y ;
    }
};

int main()
{
  Demo d1;
  Demo d2(10,20);
  Demo d3(10);

  d1.print();
  d2.print();
  d3.print();
  return 0;
}

Output –

Values are : 0 and 0
Values are : 10 and 20
Values are : 10 and 10

In the above example, depending upon the parameters passed( similar as function overloading), the appropriate constructor was called, this is the basic functionality of constructor overloading.

Constructor Overloading in C++

C++ Constructor Overloading

Implementation for Constructor Overloading

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