; read input

(defun read-input(p)
(cond
	((null p) nil)
    (T (cons p (read-input (read nil nil))))
)
)

(defun readinput(i)
	(cdr (read-input 1))
)
;--don't change above this line


; write your function here
(defvar start (readinput nil))

;Flat list

(defun flatten (list)
    (cond
        ((null list) nil)
        ((atom (car list)) (cons (car list) (flatten (cdr list))))
        (t (append
            	(flatten (car list))
            	(flatten (cdr list))
            ))
        )

    )


;dolzina na vgnezdena lista
(defun len (list)
    (cond
        ((null list) 0)
        ((atom (car list)) (+ 1 (len (cdr list))))
        (t (+ (len (car list)) (len (cdr list))))
        )
    )

;proverka za parnost na indeks i nivo
(defun paren (index)
    (cond
        ((eq(mod index 2) 0)t)
        (t nil)
        )
    )

(defun neparen (index)
    (cond
        ((eq(mod index 2) 0) nil)
        (t t)
        )
    )

;broenje kolku pati se pojavuva element vo lista
(defun countIt (list el)
    (cond
        ((null list) 0)
        ((eq (car list) el) (+ 1 (countIt (cdr list) el)))
        ((listp (car list)) (+ (countIt (car list) el) (countIt (cdr list) el)))
        (t (countIt (cdr list) el))
        )

    )

;brisi element spored baranjeto
(defun pomosna (el list level counter)
	    (cond
            ((null list) nil)
            ((and (atom (car list)) (eq (car list) el))
            	(if (and (paren (+ counter 1)) (neparen level))
                    (pomosna el (cdr list) level (+ counter 1))
                    (cons (car list) (pomosna el (cdr list) level (+ counter 1))) )
            )
            ((listp (car list))
            	(cons
                 	(pomosna el (car list) (+ level 1) counter)
                 	(pomosna el (cdr list) level (+ counter (countIt (car list) el)))
                 )
            )
            (t (cons (car list) (pomosna el (cdr list) level counter)))
            )
)

(defun trans (list flat rezult)
    (setq after (pomosna (car flat) list 0 0))
    (cond
        ((null flat) rezult)
        (t
         (trans after (remove (car flat) flat) after)
         )
        )
    )

;glavna funkcija
(defun transformiraj (list)
    (cond
        ((null list) nil)
        (t (trans list (flatten list) '()))
        )
    )

;--don't change below this line
(print (transformiraj start))