public class Solution {
    public static void main(String[] args) throws Exception {
        ArrayList<String> list = new ArrayList<String>();
        BufferedReader str = new BufferedReader(new InputStreamReader(System.in));
        for (int i = 0; i < 10; i++) {
            list.add(str.readLine());
        }

        ArrayList result = doubleValues(list);
        for (int i = 0; i < result.size(); i++) {
            System.out.println(result.get(i));
        }

        // Вывести на экран result
    }

    public static ArrayList doubleValues(ArrayList<String> list) {
        for (int i = 0; i < list.size(); i++) {
            list.add(i,list.get(i));
            i++;
        }
        return list;
    }
}