04. SoftUni Parking

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

namespace SoftUniParking
{
    class Program
    {
        public static void Main()
        {
            Dictionary<string, string> parkingUsers = new Dictionary<string, string>();

            int commandCount = int.Parse(Console.ReadLine());

            for (int i = 0; i < commandCount; i++)
            {
                string[] current = Console.ReadLine().Split(" ");

                string command = current[0];
                string user = current[1];

                if (command == "register")
                {
                    if (!parkingUsers.ContainsKey(user))
                    {
                        string number = current[2];
                        parkingUsers.Add(user, number);
                        Console.WriteLine($"{user} registered {number} successfully");
                    }
                    else
                    {
                        Console.WriteLine($"ERROR: already registered with plate number {parkingUsers[user]}");
                    }
                }
                else
                {
                    if (parkingUsers.ContainsKey(user))
                    {
                        parkingUsers.Remove(user);
                        Console.WriteLine($"{user} unregistered successfully");
                    }
                    else
                    {
                        Console.WriteLine($"ERROR: user {user} not found");
                    }
                }

            }

            foreach (var user in parkingUsers)
            {
                Console.WriteLine($"{user.Key} => {user.Value}");
            }
        }
    }
}