(defun main (&rest argv)
  (declare (ignorable argv))
  (let* ((n (read))
         (v (make-array n))
         (dp (make-array (1+ n) :initial-element (cons 0 0))))
    (dotimes (i n)
      (setf (aref v i) (read)))
    (loop for i from 1 to n do
          (setf (aref dp i) (cons (max (car (aref dp (1- i))) (cdr (aref dp (1- i))))
                                  (+ (car (aref dp (1- i))) (aref v (1- i)))))
          finally (format t "~D~%" (max (car (aref dp n)) (cdr (aref dp n)))))))

(main)