#include <iostream>
using namespace std;
class Animal {
public:
    virtual void speak() {
        cout << "Animal speak";
    }
};
class Dog : public Animal {
public:
    void speak() {
        cout << "Wang Wang";
    }
};
class Cat : public Animal {
public:
    void speak() {
        cout << "Miao Miao";
    }
};
int main() {
    Animal* p1 = new Animal();
    Animal* p2 = new Dog();
    Animal* p3 = new Cat();
    p1->speak();
    cout << " ";
    p2->speak();
    cout << " ";
    p3->speak();
    return 0;
}