Staff - Dictionaries

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

namespace sorted_dictionar
{
    class Program
    {
        static void Main(string[] args)
        {
            var phonebook = new SortedDictionary<string, string>();
            phonebook["Anna"] = "+1-555-8976";
            phonebook["Pesho"] = "+1-555-5030";
            phonebook["Bojidar"] = "+1-555-1234";
            phonebook["Nakov"] = "+359-899-555-592";
            phonebook["Nakov"] = "+359-2-981-9819"; // Replace

            Console.WriteLine(phonebook.Count);
            Console.WriteLine(string.Join(", ", phonebook.Keys));
            //Console.WriteLine(string.Join(", ", phonebook.Values));
            //phonebook.Clear();
            //Console.WriteLine(phonebook.Count);
            Console.WriteLine(phonebook.ContainsKey("Pesho"));
            Console.WriteLine(phonebook.ContainsValue("+1-555-8976"));

            foreach (string key in phonebook.Keys)
            {
                Console.WriteLine(key);
            }
            foreach (KeyValuePair<string, string> pair in phonebook)
            {
                Console.WriteLine("{0} --> {1}", pair.Key, pair.Value);
            }

            string value;
            phonebook.TryGetValue("Pesho", out value);
            Console.WriteLine(value);

        }
    }
}