using System;
using System.Linq;
using System.Collections.Generic;

namespace SoftUniParking
{
    class Program
    {
        static void Main(string[] args)
        {
            int numbersOfCommands = int.Parse(Console.ReadLine());

            var license = new Dictionary<string, string>();


            for (int i = 0; i < numbersOfCommands; i++)
            {
                string[] tokens = Console.ReadLine().Split(" ").ToArray();

                string command = tokens[0];
                string name = tokens[1];

                switch (command)
                {
                    case "register":
                        string licensePlateNumber = tokens[2];

                        if (license.ContainsKey(name))
                        {
                            Console.WriteLine($"ERROR: already registered with plate number {licensePlateNumber}");
                        }
                        else
                        {
                            Console.WriteLine($"{name} registered {licensePlateNumber} successfully");
                            license.Add(name, licensePlateNumber);
                        }
                        break;
                    case "unregister":
                        if (license.ContainsKey(name))
                        {
                            license.Remove(name);
                            Console.WriteLine($"{name} unregistered successfully");
                        }
                        break;
                }
            }
            foreach (var kvp in license)
            {
                Console.WriteLine($"{kvp.Key} => {kvp.Value}");
            }
        }
    }
}