using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        IList<Deviation> deviations = new List<Deviation>(){ new Deviation(){ ID = 1 }};

        foreach (Deviation dev in deviations.Where(d => d.ID > 0))

        {

            Console.WriteLine(dev.Duty.Text);

            Console.WriteLine(DeviationCalculations.GetLastDutyEndDateAndTimeForSubsequentDeviations(deviations, dev));

            Console.WriteLine(DeviationCalculations.GetFirstDutyStartDateAndTimeForSubsequentDeviations(deviations, dev));

            Console.WriteLine(dev.Text);

        }

    }

}

​

public class Duty

{

    public long ID;

    public string Text;

}

​

public class Deviation

{

    public long ID;

    public string Text;

    public DateTime ValidEndDateAndTime;

    public DateTime ValidStartDateAndTime;

    public Duty Duty;

}

​

public class DeviationCalculations

{

    public static DateTime GetLastDutyEndDateAndTimeForSubsequentDeviations(IList<Deviation> sortedDeviations, Deviation deviation)

    {

        DateTime lastDutyEndDate = deviation.ValidEndDateAndTime;

​

        for (int i = 0; i < sortedDeviations.Count; i++)

        {

            if (sortedDeviations[i].ValidStartDateAndTime == lastDutyEndDate)

            {

                lastDutyEndDate = sortedDeviations[i].ValidEndDateAndTime;

            }

        }

​

        return lastDutyEndDate;

    }

        public static DateTime GetFirstDutyStartDateAndTimeForSubsequentDeviations(IList<Deviation> sortedDeviations, Deviation deviation)

        {

            DateTime firstDutyStartDate = deviation.ValidStartDateAndTime;

​

            for (int i = sortedDeviations.Count - 1; i >= 0; i--)

            {

                if (sortedDeviations[i].ValidEndDateAndTime == firstDutyStartDate)

                {

                    firstDutyStartDate = sortedDeviations[i].ValidStartDateAndTime;

                }

            }

​

            return firstDutyStartDate;

        }

}