using System.Collections.Generic;
using System.Diagnostics;
public static void Main()
var list = new List<Guid>();
var dictionary = new Dictionary<Guid, int>();
var hashset = new HashSet<Guid>();
for(var i = 0; i < 30000; i++) {
var firstidguid = list[15000].ToString();
var firstid = Guid.Parse(firstidguid);
var stopwatch = new Stopwatch();
for(var i = 0; i < 10000; i++) {
var x = list.Contains(firstid);
Console.WriteLine($"List took {stopwatch.Elapsed}");
for(var i = 0; i < 10000; i++) {
var x = dictionary.ContainsKey(firstid);
Console.WriteLine($"Dictionary took {stopwatch.Elapsed}");
for(var i = 0; i < 10000; i++) {
var x = hashset.Contains(firstid);
Console.WriteLine($"Set took {stopwatch.Elapsed}");