import java.util.ArrayDeque;
import java.util.Scanner;

public class Main{

    public static void main(String[] args) {
        ArrayDeque<String> deque = new ArrayDeque<>();
        Scanner scanner = new Scanner(System.in);
        while (scanner.hasNext()) {
            String name = scanner.next();
            // 初始化队列中的数据
            deque.offerLast(name);
        }
        int count=0;
        while (true)
        {
            if(count%2==0)
            {
                System.out.println(deque.pollFirst());
                count++;
            }
            else if (count!=5)
            {
                System.out.println(deque.pollLast());
                count++;
            }
            else
            {
                return;
            }
        }
    }

}