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Understanding Constructors in C++

What are Contructors in C++?
Ans: Constructor are special function that can help initialize an object.
Do we really need contructors in C++?
Well, Its a good feature and really helps programmer.
I am a good programmer and I don't Need contructors.
LOL !!!!!
Ok enough of chit chat, lets get to the point. Why contructors were included in C++. The answer lies in very nature of programmers. Programmer frequently get messy with code and allow mistakes to happen ( LOL :P). How? Lets have a look on following code :



#include<iostream>

using namespace std;

int main()
{
int k;
cout<<k;
}
This is a classical example of programmer forgetting to initialize the variable. Hence causing unexpected errors. This problem gets more complicated as we start creating objects. Since objects may have many data, its a very common mistake to forget to initialize the data portions of objects. This is where construcors come handy. The contructors have a property that they get called automatically when objects gets created.
#include<iostream>

using namespace std;
class Me
{
     int x,y;
    public:
   Me()
   {
      x=y=0;
   }
   void show()
   {
       cout<<x<<","y;
   }
};
int main()
{
  Me x;
x.show();
}
Declaring a Constructors will ensure that whatever initialization are put into the contructors to execute always whenever object gets created. Hence objects data will always will be in initialize state.
How to declare Contructors in C++?
Its really easy, just follow the following rules :
  • Contructors are public.
  • Constructors don't have any return type.
  • Constructors name is always as that of the Class.
  • Constructors with no arguments are called default constructors.
  • Constructors can be overloaded.
So next time you put some initialization code in a contructors, your object won't have garbage values in them.
Happy coding.
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