accessing base class public member from derived class - c++

Question

Is it possible to access base class public member from instance of derived class in some other locations in the program.
class base {
public:
int x;
base(int xx){
x = xx;
}
};
class derived : base {
public:
derived(int xx) : base(xx){
}
};
class main {
public:
derived * myDerived;
void m1(){
myDerived = new derived(5);
m2(myDerived);
}
void m2(derived * myDerived){
printf("%i", myDerived->x);
}
};
After above code, I got following error.
`error: 'int base::x' is inaccessible`

Answer 1

The problem is that you accidentally use private inheritance here
class derived : base {
This makes all base class members private in the derived class.
Change this to
class derived : public base {
and it will work as expected.

Answer 2

You inherit privately from the base class. What you typically need is public inheritance:
class derived : public base
Here is the FAQ on private inheritance.

Answer 3

You should inherit from base publicly, then.
class derived : public base {
public:
derived(int xx) : base(xx){
}
};
Private inheritance is used in very specific circumstances, such as when you have a has-a relationship between two classes, but you also need to override a member of the base class.

Answer 4

From outside the class, you can only access public members of public base classes; and inheritance is private by default when you define a class using the class keyword.
To make it accessible, you need public inheritance:
class derived : public base
^^^^^^

Answer 5

Try:
class derived : public base {
...
};

Answer 6

Use public inheritance:
class derived : public base {
...
};
or
Make x private instead of public and use following code:
class Base {
int x;
public:
Base (int xx) {
x = xx;
}
void display() {
cout << "x = " << x << endl;
}
};
class Derived : public Base {
public:
Derived (int xx) : Base (xx) {
}
};
int main() {
Derived d1(2);
Derived *d = new Derived(10);
d->display();
d1.display();
return 0;
}