Show message using timer

    using System;
    using System.Diagnostics;
    using System.Linq;

    public class Timer
    {
        static void Main()
        {
            int interval = Int32.Parse(Console.ReadLine());
            Stopwatch sw = new Stopwatch();
            sw.Start();
            Func<int, bool> sleep = (x) =>
            {
                if (x * 1000 == sw.ElapsedMilliseconds)
                    return true;
                else
                    return false;
            };
            while (true)
            {
                if (sleep(interval) == true)
                {
                    Console.WriteLine("surprise");
                    sw.Restart();
                }
            }
        }
    }