using System;

using System.Linq;

using System.Collections.Generic;

public class Program

{

    public struct Interval {

        public DateTime start { get; set; }

        public DateTime end { get; set; }

    }

​

    public static void Main()

    {

        var interval = new Interval() {

            start = new DateTime(2020, 01, 01, 10, 04, 05),

            end   = new DateTime(2020, 01, 01, 14, 45, 38)

        };

​

        var coupures = new List<DateTime>();

        coupures.Add(new DateTime(2020, 01, 01, 03, 00, 00));

        coupures.Add(new DateTime(2020, 01, 01, 10, 30, 00));

        coupures.Add(new DateTime(2020, 01, 01, 11, 00, 00));

        coupures.Add(new DateTime(2020, 01, 01, 11, 30, 00));

        coupures.Add(new DateTime(2020, 01, 01, 14, 00, 00));

        coupures.Add(interval.start.AddSeconds(3600));

        coupures = coupures.Where(c => c > interval.start && c < interval.end).ToList();

        coupures.Sort();

        coupures = coupures.Prepend(interval.start).ToList();

        coupures.Add(interval.end);

        for (int i = 0; i < coupures.Count() - 1; i++) {

            Console.WriteLine($"{coupures[i]} -> {coupures[i+1]}");

        }

    }

}