Why are virtual functions needed in C++? Explain with an example

Hello, colleagues! I've just started learning C++ and I can't understand the purpose of virtual functions. I've read many articles, but it's still a mess in my head. For example, I have a base class Animal and two derived classes Dog and Cat. I want each animal to have its own sound. Here's how I did it without virtual functions: ```cpp #include #include class Animal { public: void speak() { std::cout << "Some generic animal sound\n"; } }; class Dog : public Animal { public: void speak() { std::cout << "Woof!\n"; } }; class Cat : public Animal { public: void speak() { std::cout << "Meow!\n"; } }; int main() { std::vector zoo; zoo.push_back(new Dog()); zoo.push_back(new Cat()); for (auto animal : zoo) {