using System;
using System.Collections.Generic;

public class Test
{
    static void Main(string[] args)
    {
        var set = new HashSet<MyClass>
        {
        	new MyClass { Value = 1 },
        	new MyClass { Value = 2 }
        };
        foreach (var x in set)
            Console.WriteLine(x.Value);
    }
}

class MyClass
{
    public int Value { get; set; }
    public override int GetHashCode() => 0;
}