Write a C++ program where a function which is not the part of the class can access the private data member

#include<conio.h>
#include<iostream.h>
class abc
{
  private:
    int n;
  public:
abc()
    {
      n=0;
    }
    void getdata()
    {
      cout<<"\n"<<"Enter the value of N: ";
      cin>>n;
    }
    void show()
    {
      cout<<"\n"<<"Total Sum is: "<<n;
    }
abc add(abc);
};

abcabc::add(abc h1)
{
  n=n+h1.n;
}
void main()
{
abc h1,h2;
  clrscr();
  h1.getdata();
  h2.getdata();
  h2.add(h1);
  h2.show();
  getch();
}





OUTPUT
Enter the value of N:4
Enter the value of N:5

Total sum is:9