hiding.cpp

class A
{
  void Foo();
}
class B : public A
{
  //intended to override A's Foo, but hides it, because A's Foo is non virtual
  //including override here would allow the compiler to catch the error
  virtual void Foo();
}

A* myptr = new B();
myptr->Foo(); //calls A's Foo

Fix is to make A's Foo virtual, but override will help you realize the error