llllll

(defun equal-lists-p (a b)
  (or (and (null a) (null b))
      (and (consp a)
           (consp b)
           (eql (car a) (car b))
           (or
            (and
             (not (cdr a))
             (not (cdr b)))
            (equal-lists-p (cdr a) (cdr b))))))