9.4. Initializing a New Game of Grand Theft Wumpus

With our graph construction stuff out of the way, we can write a simple function that initializes a brand-new game of Grand Theft Wumpus:

(defun new-game ()
    (setf *congestion-city-edges* (make-city-edges))
    (setf *congestion-city-nodes* (make-city-nodes *congestion-city-edges*))
   (setf *player-pos* (find-empty-node))
    (setf *visited-nodes* (list *player-pos*))
    (draw-city))