#include <iostream>
using namespace std;

class Animal {
public:
  string name;
  void eat() { cout << name << " eats" << endl; }
};

class Dog {
public:
  Animal base;
  void bark() { cout << base.name << " barks" << endl; }
};

int main() {
  Dog d;
  d.base.name = "Rex";
  d.base.eat();
  d.bark();
  return 0;
}