class LinkedList{
	friend void draw(const LinkedList & list, byte_t color, byte_t *where);	
	private:
		class Link{
		private:
			Circle *rock;
		public:
			Link * next;
			Link(Circle r,Link * ptr);
			~Link();
			bool ok;
			void display(byte_t color, byte_t *where);
			Circle me();
			void fly(int ticks, const Vector &s=Vector(0,0));
			bool on(Vector p);
			double getsize();
			void size(unsigned r);
			Vector getcenter();
		};
		Link *head;
	public:
		LinkedList();
		~LinkedList();
		void add(Circle r);
		void remove();
		void collide(Ship &ship);
		void fly(int ticks, const Vector &s=Vector(0,0));
		bool cleared();
};