using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main(string[] args)

    {

        TimeSpan resolution = TimeSpan.FromMinutes(1);

        IEnumerable<DateTime> readings = GetReadings(resolution).ToList();

​

        // Implement identify missing readings

        IEnumerable<DateTime> missingReadings = readings.IdentifyMissingReadings(resolution);

​

        foreach (var missingReading in missingReadings)

        {

            Console.WriteLine(missingReading.ToShortTimeString());

        }

​

        Console.ReadLine();

    }

    // Don't change this method

    private static IEnumerable<DateTime> GetReadings(TimeSpan resolution)

    {

        Random random = new Random();

        int readings = 99;

        DateTime currentDate = DateTime.Now.Date;

        yield return currentDate;

        for (int x = 0; x < readings; x++)

        {

            currentDate += resolution;

            if (random.Next(10) > 0)

            {

                yield return currentDate;

            }

        }

    }

}