Quiz 56

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description:

The code is ill-formed. Virtual functions must have a unique "final overrider" that overrides all other instances of that function in its inheritance heirarchy. In this case neither Box::print nor Sphere::print override each other, so the condition is not met and the GeoDisc class is ill-formed.

#include <iostream>
struct Shape
{
  virtual void print()
  {
    std::cout << "SHAPE" << std::endl;
  }
  virtual ~Shape() {}
};
struct Box : public virtual Shape
{
  void print()
  {
    std::cout << "BOX" << std::endl;
  }
};
struct Sphere : public virtual Shape
{
  void print()
  {
    std::cout << "SPHERE" << std::endl;
  }
};
struct GeoDisc : public Box, public Sphere
{
};
int main(int argc, char** argv)
{
  Shape* s = new GeoDisc;
  s->print();
  delete s;
  return 0;
}