using System;

​

using System.Diagnostics;

public class Program

{

    public static void Main()

    {

        TimeSpan timeSpan = TimeSpan.FromTicks(-1231231231231);

        Console.WriteLine("Original timespan: " + timeSpan);

        // Measure the time for the integer rounding method (without floating-point math)

        Stopwatch stopwatch1 = Stopwatch.StartNew();

        long baseMilliseconds = timeSpan.Ticks / TimeSpan.TicksPerMillisecond;

        long remainder1 = timeSpan.Ticks % TimeSpan.TicksPerMillisecond;

​

        // Add an extra millisecond if the remainder is at least half of a millisecond tick

        if (Math.Abs(remainder1) >= TimeSpan.TicksPerMillisecond / 2)

        {

            baseMilliseconds += Math.Sign(timeSpan.Ticks);

        }

​

        TimeSpan rounded1 = TimeSpan.FromTicks(baseMilliseconds * TimeSpan.TicksPerMillisecond);

        stopwatch1.Stop();

        Console.WriteLine("Integer rounding method time (in ms): " + stopwatch1.Elapsed.TotalMilliseconds);

        Console.WriteLine("Rounded1 Result: " + rounded1);

         // Measure the time for the second rounding method

        Stopwatch stopwatch2 = Stopwatch.StartNew();

        long adjustment = 0;

        long remainder = timeSpan.Ticks % TimeSpan.TicksPerMillisecond;

        if (remainder != 0)

            adjustment = Math.Abs(remainder) < TimeSpan.TicksPerMillisecond / 2

                ? -remainder

                : TimeSpan.TicksPerMillisecond - (remainder * Math.Sign(timeSpan.Ticks));

        TimeSpan rounded2 = TimeSpan.FromTicks(timeSpan.Ticks + adjustment);

        stopwatch2.Stop();

        Console.WriteLine("Second rounding method time (in ms): " + stopwatch2.Elapsed.TotalMilliseconds);

        Console.WriteLine("Rounded2 Result: " + rounded2);

    }

}