using System;

using System.Linq;

public class Program

{

    public static void Main()

    {

        var myClass = new MyClass();

        var myClassDuplicate = new MyClass();

        var allInstances = new [] { myClass, myClassDuplicate };

        var deduplicatedInstances = allInstances.Distinct();

        Console.WriteLine(deduplicatedInstances.Count());

    }

    public class MyClass

    {

        public string FirstMember { get; } = "foo";

        public string SecondMember { get; } = "bar";

        public override bool Equals(object obj) {

            if (obj is MyClass otherClass)

            {

                return this.FirstMember == otherClass.FirstMember && this.SecondMember == otherClass.SecondMember;

            }

            return false;

        }

        public override int GetHashCode()

        {

            return this.FirstMember.GetHashCode() ^ this.SecondMember.GetHashCode();

        }

    }

}