if (the key member function inherited from class wabbit says that
		the user pressed a key k) {

		for (search the array of structures using a pointer p) {
			if (k == p->c) {
				*dx = p->dx;
				*dy = p->dy;
				return;
			}
		}

		punish();   //Punish user who pressed an illegal key.
	}

	//Arrive here if the user pressed no key, or pressed an illegal key.
	*dx = *dy = 0;
}