Copy Constructor C++

•Initializes a new object from another, existing one

•Signature:

Class::Class(Class &obj)

{

}

Date::Date(Date &date)

{

// no need to check passed date arg

  month = date.month;

  day   = date.day;

  year  = date.year;

}

//Example

#include <iostream>
using namespace std;

class a{
int x; //private
public:
int getX(){return x;}
void setX(int a){
x = a;
}

void copyConstructor(a &obj);
};

void a::copyConstructor(a &obj){
x  =  obj.x;
}

int main(){
a obj;
obj.setX(10);//Functions are called over objects.
cout << "x = " << obj.getX() << endl;
a obj1;
obj1.copyConstructor(obj);
cout << "obj1 = " << obj1.getX() << endl;
return 0;
}