Program for Copy Constructor Using OOPs & C++ concept

#include<iostream.h>
#include<conio.h>
class A
{
int a;
public:
A()         //default Constructor
{}
A(int x)  //Parameterized Constructor
{
a=x;
}
A(const A &x)       //Copy Constructor
{
a=x.a;
}
void display()      
{
cout<<"A::"<<a<<endl;

}
};
void main()
{
A obj1(10);
A obj2(obj1);
A obj3=obj1;

obj1.display();
obj2.display();
obj3.display();
getche();
}