public class E04ParkingLot {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        List<String> list = new ArrayList<>();
        String[] input = sc.nextLine().split(", ");

        while (!input[0].equals("END")) {

            if (input[0].equals("IN")) {
                list.add(input[1]);
            } else {
                list.remove(input[1]);
            }

            input = sc.nextLine().split(", ");
        }

        if (list.isEmpty()) {
            System.out.println("Parking Lot is Empty");
        } else {
            list.forEach(System.out::println);
        }
    }
}