Why can't I access a protected member from an instance of a derived class?

Question

I haven\'t done C++ in a while and can\'t figure out why following doesn\'t work:

class A {
protected:
  int num;
};

class B : public A {
};

main () {
  B          


        

Answer 1

yes protected members are accessible by derived classes but you are accessing it in the main() function, which is outside the hierarchy. If you declare a method in the class B and access num it will be fine.