Continents - Dictionary<string, Dictionary<string, List<stri

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Cities_by_Continent_and_Country
{
    class Program
    {
        static void Main(string[] args)
        {
            Dictionary<string, Dictionary<string, List<string>>> continents = new Dictionary<string, Dictionary<string, List<string>>>();
            int cnt = int.Parse(Console.ReadLine());

            for (int i = 0; i < cnt; i++)
            {
                string[] input = Console.ReadLine().Split(' ').ToArray();
                string continent = input[0];
                string country = input[1];
                string city = input[2];

                if (!continents.ContainsKey(continent))
                {
                    continents[continent] = new Dictionary<string, List<string>>();
                }
                if (!continents[continent].ContainsKey(country))
                {
                    continents[continent][country] = new List<string>();
                }
                continents[continent][country].Add(city);
            }
            foreach (KeyValuePair<string, Dictionary<string, List<string>>> continent in continents)
            {
                string name = continent.Key;
                Dictionary<string, List<string>> countries = continent.Value;
                Console.WriteLine($"{name}:");
                foreach(KeyValuePair <string, List<string>> country in countries)
                {
                    string nameCountry = country.Key;
                    List<string> cities = country.Value;
                    Console.WriteLine("{0} -> {1}", nameCountry, string.Join(", ", cities));
                }
            }
        }
    }
}