(require '[clojure.string :as str])
;; (require '[clojure.core.match :refer [match]])
(when (some #(= "--debug" %) *command-line-args*)
  (require '[my-debug]))

(defn ii [] (Integer/parseInt (read-line)))
(defn li [] (map #(Integer/parseInt %) (str/split (read-line) #" ")))
(def hd first)
(def tl rest)
(defn yn [b] (println (if b "Yes" "No")))

(defn divmod [a b]
  [(quot a b) (rem a b)])


(let [N (ii)
      [d m] (divmod N 2)]
  (println (+ d m)))