SoftUniParking

using System;
using System.Collections.Generic;

namespace SoftUniParking
{
    class Program
    {
        static void Main(string[] args)
        {
            var registrationDictionary = new Dictionary<string, string>();
            int numberOfLines = int.Parse(Console.ReadLine());
            for (int i = 0; i < numberOfLines; i++)
            {
                string input = Console.ReadLine();
                string[] inputArray = input.Split();
                if (inputArray[0] == "register")
                {
                    string user = inputArray[1];
                    string number = inputArray[2];
                    if (registrationDictionary.ContainsKey(user) == false)
                    {
                        registrationDictionary[user] = number;
                        Console.WriteLine($"{user} registered {number} successfully" );
                    }

                    else
                    {
                        Console.WriteLine($"ERROR: already registered with plate number {number}");
                    }
                }

                else if(inputArray[0] == "unregister")
                {
                    string user = inputArray[1];
                    if (registrationDictionary.ContainsKey(user)==false)
                    {
                        Console.WriteLine($"ERROR: user {user} not found");
                    }

                    else
                    {
                        registrationDictionary.Remove(user);
                        Console.WriteLine($"{user} unregistered successfully");
                    }
                }
            }

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

      }
    }