Access the non-public members of the class:C++

Hi, I am studying in the Second year of the BscIT. I have C++ language in syllabus. I have the little bit knowledge about the C++. My teacher gave me an assignment on the functions that make the use of private members of the class. SoI want to know about how can make the use of non public members of the base class? Is there any function or method that allows me to do this. If any then what it is? If anyone knows about it then help me.
Reply me!

Hello, I think the answer to your question is that you require Friend function. For accessing the non-public members of a class Friend functions are used . Whenever a data is declared as private inside a base class, then it is not accessible from outside the class. A class can only allow non-member functions and other classes to access its own private data, by making them as friend. A Friend function is a function or a member of another class. Friend function is also Global friend. I hope it is enough to know you how can we access the private members of the class outside it.

I guess it helps you to make your assignment:
Properties of Friend function:
1) Friend of the one class can be the member of some another class.
2) A friend is known as GLOBAL FRIEND.
3) Friend can access the non-public or protected members of the class in which they are declared as friend.
4) Friends do not get “this” pointer.
5) Friends can be friend of more than one class.
6) Friend can be declared anywhere in the class.

This example shows you the use of friend function. Friend function abc is a member of class B and accesses the private data members p and q of class A.

#include <iostream>
using namespace std;

class A;
class B
{
public:
void print(A& y);
};

class A
{
int p,q;
friend void B::print(A& y);
public:
A() : p(1), q(2) { }
};

void B::print(A& y)
{
cout << "p is " << y.p << endl;
cout << "q is " << y.q << endl;
}

int main()
{
A yobj;
B sobj;
sobj.print(yobj);
}