(eval-when (:compile-toplevel :load-toplevel :execute)
  (sb-int:defconstant-eqx OPT
    #+swank '(optimize (speed 3) (safety 2))
    #-swank '(optimize (speed 3) (safety 0) (debug 0))
    #'equal)
  #+swank (ql:quickload '(:cl-debug-print :fiveam) :silent t)
  #-swank (set-dispatch-macro-character
           ;; enclose the form with VALUES to avoid being captured by LOOP macro
           #\# #\> (lambda (s c p) (declare (ignore c p)) `(values ,(read s nil nil t)))))
#+swank (cl-syntax:use-syntax cl-debug-print:debug-print-syntax)
#-swank (disable-debugger) ; for CS Academy

;; BEGIN_INSERTED_CONTENTS
;;;
;;; Complement to the bitwise operations in CLHS
;;;

(eval-when (:compile-toplevel :load-toplevel :execute)
  (assert (= sb-vm:n-word-bits 64)))

;; KLUDGE: a variant of DPB that handles a 64-bit word efficiently
(defmacro u64-dpb (new spec int)
  (destructuring-bind (byte s p) spec
    (assert (eql 'byte byte))
    (let ((size (gensym)) (posn (gensym)) (mask (gensym)))
      `(let* ((,size ,s)
              (,posn ,p)
              (,mask (ldb (byte ,size 0) -1)))
         (logior (the (unsigned-byte 64) (ash (logand ,new ,mask) ,posn))
                 (the (unsigned-byte 64) (logand ,int (lognot (ash ,mask ,posn)))))))))

(defconstant +most-positive-word+ #.(- (ash 1 64) 1))

;; TODO: right shift
(defun bit-lshift (bit-vector delta &optional result-vector end)
  "Left-shifts BIT-VECTOR by DELTA bits and fills the new bits with zero.
The behaviour is the same as the bit-wise operations in CLHS: The result is
copied to RESULT-VECTOR; if it is T, BIT-VECTOR is destructively modified; if it
is NIL, a new bit-vector of the same length is created. If END is specified,
this function shifts only the range [0, END) of BIT-VECTOR and copies it to the
range [0, END+DELTA) of RESULT-VECTOR.

Note that here `left' means the direction from a smaller index to a larger one,
i.e. (bit-lshift #*1011000 2) |-> #*0010110"
  (declare #.OPT
           (simple-bit-vector bit-vector)
           ((or null (eql t) simple-bit-vector) result-vector)
           ((integer 0 #.most-positive-fixnum) delta)
           ((or null (integer 0 #.most-positive-fixnum)) end))
  (setq result-vector
        (etypecase result-vector
          (null (make-array (length bit-vector) :element-type 'bit :initial-element 0))
          ((eql t) bit-vector)
          (simple-bit-vector result-vector)))
  (setq end (or end (length bit-vector)))
  (assert (<= end (length bit-vector)))
  (setq end (min end (max 0 (- (length result-vector) delta))))
  (multiple-value-bind (d/64 d%64) (floor delta 64)
    (declare (optimize (safety 0))
             (simple-bit-vector result-vector))
    (multiple-value-bind (end/64 end%64) (floor end 64)
      ;; process the last word separately
      (unless (zerop end%64)
        (let ((word (sb-kernel:%vector-raw-bits bit-vector end/64)))
          (setf (sb-kernel:%vector-raw-bits result-vector (+ end/64 d/64))
                (u64-dpb word
                         (byte (min end%64 (- 64 d%64)) d%64)
                         (sb-kernel:%vector-raw-bits result-vector (+ end/64 d/64))))
          (when (> end%64 (- 64 d%64))
            (setf (ldb (byte (- end%64 (- 64 d%64)) 0)
                       (sb-kernel:%vector-raw-bits result-vector (+ 1 end/64 d/64)))
                  (ldb (byte (- end%64 (- 64 d%64)) (- 64 d%64)) word)))))
      ;; Body. We avoid LDB and DPB here for efficiency, though this seems to
      ;; be somewhat incomprehensible...
      (let* ((mask0 (ldb (byte 64 0) (lognot (ldb (byte d%64 0) -1))))
             (mask1-lo (ldb (byte (- 64 d%64) 0) -1))
             (mask1-hi (ldb (byte 64 0) (lognot (ash mask1-lo d%64)))))
        (declare ((unsigned-byte 64) mask0 mask1-lo mask1-hi))
        (do ((i (- end/64 1) (- i 1)))
            ((< i 0))
          (let ((word (sb-kernel:%vector-raw-bits bit-vector i))
                (i+d/64 (+ i d/64)))
            (declare ((unsigned-byte 64) word)
                     ((mod #.most-positive-fixnum) i+d/64))
            (setf (sb-kernel:%vector-raw-bits result-vector i+d/64)
                  (logior (the (unsigned-byte 64)
                               (ash (logand word mask1-lo) d%64))
                          (logand (sb-kernel:%vector-raw-bits result-vector i+d/64)
                                  mask1-hi)))
            (setf (sb-kernel:%vector-raw-bits result-vector (+ 1 i+d/64))
                  (logior (ash word (- d%64 64))
                          (logand (sb-kernel:%vector-raw-bits result-vector (+ 1 i+d/64))
                                  mask0))))))
      ;; zero padding
      (when (< d/64 (ceiling (length result-vector) 64))
        (setf (ldb (byte d%64 0) (sb-kernel:%vector-raw-bits result-vector d/64)) 0))
      ;; REVIEW: May we set the last word of a bit vector to zero beyond the
      ;; actual bound?
      (dotimes (i (min d/64 (ceiling (length result-vector) 64)))
        (setf (sb-kernel:%vector-raw-bits result-vector i) 0))
      result-vector)))

(defmacro dbg (&rest forms)
  #+swank
  (if (= (length forms) 1)
      `(format *error-output* "~A => ~A~%" ',(car forms) ,(car forms))
      `(format *error-output* "~A => ~A~%" ',forms `(,,@forms)))
  #-swank (declare (ignore forms)))

(defmacro define-int-types (&rest bits)
  `(progn
     ,@(mapcar (lambda (b) `(deftype ,(intern (format nil "UINT~A" b)) () '(unsigned-byte ,b))) bits)
     ,@(mapcar (lambda (b) `(deftype ,(intern (format nil "INT~A" b)) () '(signed-byte ,b))) bits)))
(define-int-types 2 4 7 8 15 16 31 32 62 63 64)

(declaim (inline println))
(defun println (obj &optional (stream *standard-output*))
  (let ((*read-default-float-format* 'double-float))
    (prog1 (princ obj stream) (terpri stream))))

(defconstant +mod+ 1000000007)

;;;
;;; Body
;;;

(defun main ()
  (declare #.OPT)
  (let* ((n (read))
         (dp (make-array 4000001 :element-type 'bit :initial-element 0))
         (tmp (make-array 4000001 :element-type 'bit :initial-element 0))
         (sum 0))
    (declare (uint32 n sum))
    (dotimes (i n)
      (let ((a (read)))
        (incf sum a)
        (setf (aref dp 0) 1)
        (bit-lshift dp a tmp)
        (bit-ior dp tmp t)))
    (loop for x from (ceiling sum 2) below (length dp)
          when (= (aref dp x) 1)
          do (println x)
             (return-from main))))

#-swank (main)

;;;
;;; Test and benchmark
;;;

#+swank
(defun io-equal (in-string out-string &key (function #'main) (test #'equal))
  "Passes IN-STRING to *STANDARD-INPUT*, executes FUNCTION, and returns true if
the string output to *STANDARD-OUTPUT* is equal to OUT-STRING."
  (labels ((ensure-last-lf (s)
             (if (eql (uiop:last-char s) #\Linefeed)
                 s
                 (uiop:strcat s uiop:+lf+))))
    (funcall test
             (ensure-last-lf out-string)
             (with-output-to-string (out)
               (let ((*standard-output* out))
                 (with-input-from-string (*standard-input* (ensure-last-lf in-string))
                   (funcall function)))))))

#+swank
(defun get-clipbrd ()
  (with-output-to-string (out)
    (run-program "powershell.exe" '("-Command" "Get-Clipboard") :output out :search t)))

#+swank (defparameter *this-pathname* (uiop:current-lisp-file-pathname))
#+swank (defparameter *dat-pathname* (uiop:merge-pathnames* "test.dat" *this-pathname*))

#+swank
(defun run (&optional thing (out *standard-output*))
  "THING := null | string | symbol | pathname

null: run #'MAIN using the text on clipboard as input.
string: run #'MAIN using the string as input.
symbol: alias of FIVEAM:RUN!.
pathname: run #'MAIN using the text file as input."
  (let ((*standard-output* out))
    (etypecase thing
      (null
       (with-input-from-string (*standard-input* (delete #\Return (get-clipbrd)))
         (main)))
      (string
       (with-input-from-string (*standard-input* (delete #\Return thing))
         (main)))
      (symbol (5am:run! thing))
      (pathname
       (with-open-file (*standard-input* thing)
         (main))))))

#+swank
(defun gen-dat ()
  (uiop:with-output-file (out *dat-pathname* :if-exists :supersede)
    (format out "")))

#+swank
(defun bench (&optional (out (make-broadcast-stream)))
  (time (run *dat-pathname* out)))

;; To run: (5am:run! :sample)
#+swank
(it.bese.fiveam:test :sample
  (it.bese.fiveam:is
   (common-lisp-user::io-equal "3
1 2 1
"
    "2
"))
  (it.bese.fiveam:is
   (common-lisp-user::io-equal "1
58
"
    "58
")))


Measured memory_bytes: 26976