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;
}
}
}
}