Copy constructor in C++

/* Create demo class and two member function 1st one is getting data and second one is display data*/
/*

Output of program is
sum of object a1 x and obj a2 x is 40
*/

#include<iostream.h>
#include<stdio.h>
#include<conio.h>
class demo
{
    //public:
    int age;
    char name[20];//data member;
    public:   //private,protected,public (by def private)
    void getData()//member function
    {
        cout<<"\nEnter your name:";
        cin>>name;
        cout<<"\nEnter your age:";
        cin>>age;
    }

    void display()//member function
    {
        cout<<"\nYour name is "<<name<<" and age is "<<age;
    }
};
int main()
{
    demo d1;//d1 is object
    clrscr();
    cout<<"\n\n";
    cout<<d1.age;
    d1.getData();
    d1.display();
    getch();
    return 0;
}