(ns my.core
  (:require [clojure.string :as str]))


;(def w (str (read-string (read-line))))


(def input (read-line))

(def t (Integer/parseInt (first (str/split input #" "))))

(defn twice []
  (let [g (read-line)]
    (println g)
    (println g)))

(defn p [_ t]
  (if (zero? t)
    nil
    (recur (twice) (dec t))))

(p nil t)