class Observer  //观察者

{

public:

	virtual void upadte() = 0; //接受通知

};

class Manager // 管理者

{

public:

	virtual void registerObserver(Observer* o) = 0; //注册观察者

	virtual void notify() = 0; //通知所有的观察者

};

class ManagerImpl: public Manager

{

	vector<Observer*> v;

public:

	void registerObserver(Observer* o)

	{

		v.push_back(o);

	}

	void notify()

	{

		for(int i=0; i<v.size(); i++)

		{

			v[i]->upadte();

		}

	}

};

class FirstObserver: public Observer

{

public:

	void upadte()

	{

		cout << "FirstObserver::upadte()" << endl;

	}

};

class SecondObserver: public Observer

{

public:

	void upadte()

	{

		cout << "SecondObserver::upadte()" << endl;

	}

};

int main()

{

	FirstObserver* f = new FirstObserver();

	SecondObserver* s = new SecondObserver();

	ManagerImpl* m = new ManagerImpl();

	m->registerObserver(f);

	m->registerObserver(s);

	m->notify();

	return 0;

}