using System;
using System.Collections.Generic;
public class Program
{
public static void Main()
HashSet<Tweet> tweets = new HashSet<Tweet>();
var tweet = new Tweet();
tweet.id = 1;
tweet.text = "hi";
tweets.Add(tweet);
Console.WriteLine(tweets.Count);
}
public class Tweet
public int id { get; set ; }
public string text { get; set; }