;; ADD-QUEUE
;; usage: (add-queue queue '(object priority-weight))
;; or: (add-queue queue element), where 'element' is a list of pattern (element priority-weight)
(defun add-queue (queue element) 
  (cond 
	( (eq queue ()) ; if the queue is empty ...
	 (list element) ) ; ... return the element as the new queue.
	( (> (cadr element) (cadr (car queue))) ; if the element to be added has a higher priority than the car element ...
	 (append (list element) queue) ) ; ... make it the first element of the queue.
	( t ; if none of the above ...
	 (append (list (car queue)) (add-queue (cdr queue) element))) ; ... put it into the tail of the queue.
	)
)

;; TOP-QUEUE
;; usage: (top-queue queue)
(defun top-queue (queue)
  (car queue) ; The queue is ordered, so give the first element.
)

;; REMOVE-TOP-QUEUE
;; usage: (remove-top-queue queue)
(defun remove-top-queue (queue) ; The queue is ordered, so give the tail of the queue.
  (cdr queue)
)