;;; https://gitlab.com/Syndamia/senzill
(require :senzill)
(use-package :senzill.math)
(use-package :senzill.collections)
(use-package :senzill.io)

(ask-for-stream (prog-input)
  (let* ((folders '("/" 0 NIL)) (current-folder folders))
    (defun parse-cd (loc)
      (cond ((string= loc "/")
             (setf current-folder folders))
            ((string= loc "..")
             (let ((working-fold folders))
               (loop for ind in (third current-folder)
                     until (cdr (third current-folder)) do
                     (setf working-fold (nth ind working-fold)))
               (setf current-folder working-fold)))
            (t
             (setf current-folder (first (member-if (lambda (x) (string= (first x) loc))
                                                    (nthcdr 3 current-folder)))))))

    (defun parse-dir (name)
      (push-back  (list 
                   name ; name
                   0               ; sum of size of all files
                   (append (third current-folder) ; location instructions for parent
                           (list (- (length current-folder) 1))))
                 current-folder))

    (doread-lines (inpt :read-line-options (prog-input NIL))
                  (cond ((and (char= (char inpt 0) #\$) (char= (char inpt 2) #\c))
                         (parse-cd (subseq inpt 5)))
                        ((char= (char inpt 0) #\d)
                         (parse-dir (subseq inpt 4)))
                        ((digit-char-p (char inpt 0))
                         (+= (second current-folder) (parse-integer inpt :junk-allowed T))))
                  (print current-folder)
                  (force-output))
    (print folders)))