(defun main (&rest argv)
  (declare (ignorable argv))
  (let* ((tm (read))
         (n (read))
         (c (make-array n))
         (v (make-array n))
         (dp (make-array (1+ tm) :element-type 'integer :initial-element -1))
         (res 0))
    (dotimes (i n) (setf (aref c i) (read)))
    (dotimes (i n) (setf (aref v i) (read)))
    (setf (aref dp 0) 0)
    (dotimes (i n)
      (loop for j from (1- tm) downto 0
            unless (= -1 (aref dp j))
              do (let ((point (aref v i))
                       (a 0)
                       (k 1))
                   (loop while (plusp point)
                           do (progn
                                (let ((now (+ j (* k (aref c i)))))
                                  (when (<= now tm)
                                        (incf a point)
                                        (if (< (aref dp now) (+ (aref dp j) a))
                                            (setf (aref dp now) (+ (aref dp j) a))
                                            (return))))
                                (incf k)
                                (setf point (floor point 2)))))))
    (loop for i from tm downto 0 do
          (setq res (max res (aref dp i))))
    (format t "~d~%" res)))

(main)