Are static variables in a base class shared by all derived classes?

Question

If I have something like

class Base {
    static int staticVar;
}

class DerivedA : public Base {}
class DerivedB : public Base {}

Will bot

Answer 1

To ensure that each class has its own static variable, you should use the "Curiously recurring template pattern" (CRTP).

template 
class Base
{
    static int staticVar;
};

template  int Base::staticVar(0);

class DerivedA : public Base {};
class DerivedB : public Base {};