笔试面试 下面代码执行后的输出结果为? #include <iostream> using namespace std; class Animal { public: void eat() { cout << “1” << endl; } virtual void drink() { cout << “2” << endl; } }; class Dog: public Animal { public: void eat() { cout << “3” << endl; } void drink() { cout << “4” << endl; } }; int main() { Animal ani; Dog dog; Animal *p = &ani; p->eat(); p->drink(); p = &dog; p->eat(); p->drink(); Animal *ptr = (Animal*)&dog; ptr->eat(); ptr->drink(); return 0; }