using System;

using System.Linq;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        var list = new List<LoginInfoDto>();

        list.Add(new LoginInfoDto{Domain = "x1", Login = "y1"});

        list.Add(new LoginInfoDto{Domain = "x1", Login = "y2"});

        list.Add(new LoginInfoDto{Domain = "x1", Login = "y1"});

        list.Add(new LoginInfoDto{Domain = "x1", Login = "Y1"});

        list.Add(new LoginInfoDto{Domain = "x2", Login = "y3"});

        list.Add(new LoginInfoDto{Domain = "x2", Login = "y3"});

        list.Add(new LoginInfoDto{Domain = "x2", Login = "y4"});

        list.Add(new LoginInfoDto{Domain = "X2", Login = "y4"});

        list.Add(new LoginInfoDto{Domain = "x2", Login = "Y4"});

        list.Add(new LoginInfoDto{Domain = "Y2", Login = "Y4"});

        list.Add(new LoginInfoDto{Domain = "Y2", Login = "Y4"});

        list = list.GroupBy(x => (x.Domain, x.Login)).Select(x => x.First()).ToList();

        Console.WriteLine($"Total:{list.Count}");

        for (var i = 0; i < list.Count; i++)

        {

            Console.WriteLine($"{i+1}|{list[i]}");

        }

    }

    public class LoginInfoDto

    {

        public string Domain { get; set; }

        public string Login { get; set; }

        public override string ToString()

        {

            return $"{Domain} - {Login}";

        }

    }

}