When should virtual destructors be used in C++?

Hello everyone! I'm a beginner C++ developer, and I'm struggling with one question. I've just started learning about polymorphism and inheritance, and I came across this situation. Let's say I have a base class `Animal` and a derived class `Dog`. I want to use smart pointers (shared_ptr) for automatic memory management. The code looks like this: ```cpp #include #include class Animal { public: Animal() { std::cout << "Animal created\n"; } ~Animal() { std::cout << "Animal destroyed\n"; } virtual void speak() { std::cout << "Animal sound\n"; } }; class Dog : public Animal { public: Dog() { std::cout << "Dog created\n"; } ~Dog() { std::cout << "Dog destroyed\n"; } void speak() override { std::cout << "Woof!\n"; } }; int main(