piyush0101

(proclaim '(optimize (speed 3) (space 0) (debug 0)))

(defparameter *width* 80)
(defparameter *height* 23)
(defparameter *length* (* *width* *height*))

(defun neighbours (pos)
  (mapcar (lambda (x) (mod x *length*))
          (delete pos
                  (mapcan (lambda (pos)