import java.util.LinkedHashMap;
import java.util.Scanner;

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

        LinkedHashMap<String, String> data = new LinkedHashMap<>();

        int n = Integer.parseInt(scanner.nextLine());

        for (int i = 0; i < n; i++) {

            String[] input = scanner.nextLine().split("\\s+");

            String command = input[0];
            String name = input[1];


            if (command.equals("register")) {

                String plate = input[2];

                if (!data.containsKey(name)) {
                    data.put(name, plate);
                    System.out.println(
                            String.format("%s registered %s successfully",
                                    name, plate));
                } else if (data.containsKey(name)) {
                    System.out.println(
                            String.format("ERROR: already registered with plate number %s",
                                    plate));
                }
            }
            if (command.contains("unregister")) {
                if (data.containsKey(name)) {
                    data.remove(name);
                    System.out.println(
                            String.format("%s unregistered successfully",
                                    name)
                    );
                } else if (!data.containsKey(name)) {
                    System.out.println(
                            String.format("ERROR: user %s not found",
                                    name)
                    );
                }
            }
        }
        data.forEach((key, value) -> System.out.println(
                String.format("%s => %s", key, value)
        ));


    }
}