using System;

​

public class Program

{

    public static void Main()

    {

        TimeSpan tracker;

        if (TimeSpan.TryParseExact("2h 57m 43s", @"h%\h\ m%\m\ s%\s", null, out tracker))

        {

            Console.WriteLine(tracker);

        }

        else

        {

            Console.WriteLine("fail");

        }

    }

}