Question

I am learning basic concepts of OOP in C++ and I came across a logical problem.

#include <iostream>
#include <conio.h>

using namespace std;

class A {
    int i;
public:
    void set(int x) {
        i=x;
    }
    int get() {
        return i;
    }
    void cpy(A x) {
        i=x.i; 
    }
};

int main()
{
    A x, y;
    x.set(10);
    y.set(20);

    cout << x.get() << "\t" << y.get() << endl;
    x.cpy(y);
    cout << x.get() << "\t" << y.get() << endl;
    getch();
}

I wanted to know in the above code why am I able to access x.i [Line 19] ,it being a private member in the different object.Isn’t the private scope restricted to the same class even if the object is passed as a parameter?

Answer 1

private in C++ means private to the class, not private to the object. Both interpretations are possible, indeed some languages chose the other. But most languages are like C++ in this and allow objects of the same class to acces another instance’s private members.