using System;

using System.Collections.Generic;

using System.Linq;

using MoreLinq;

​

namespace MattConsole

{

    public class Program

    {

        public class Bob

        {

            public DateTime Start { get; set; }

            public DateTime End { get; set; }

        }

​

        public static void Main()

        {

            var data = new List<Bob>

            {

                new Bob() {Start = new DateTime(2000, 1, 1, 1, 0, 0), End = new DateTime(2000, 1, 1, 2, 0, 0)},

                new Bob() {Start = new DateTime(2001, 1, 1, 1, 0, 0), End = new DateTime(2001, 1, 1, 2, 0, 0)},

                new Bob() {Start = new DateTime(2001, 1, 1, 2, 0, 0), End = new DateTime(2001, 1, 1, 3, 0, 0)},

                new Bob() {Start = new DateTime(2001, 1, 1, 4, 0, 0), End = new DateTime(2001, 1, 1, 5, 0, 0)},

                new Bob() {Start = new DateTime(2001, 1, 1, 5, 0, 0), End = new DateTime(2001, 1, 1, 6, 0, 0)},

                new Bob() {Start = new DateTime(2001, 1, 1, 11, 0, 0), End = new DateTime(2001, 1, 1, 12, 0, 0)},

            };

​

            var result = data.Lag(1, (a, b) => new {a, b}).Segment(c => c.a.Start != c.b?.End).ToList();

            var result2 = result.Select(z => new { Start = z.First().a.Start, End = z.Last().a.End }).ToList();

​

            Console.ReadLine();

        }

​

    }

}

​