using System;
using System.Diagnostics;
using System.Threading;
using System.Threading.Tasks;

namespace Test
{
    class Program
    {
        public static void Main(string[] args)
        {
            var rand = new Random();
            double d = rand.NextDouble();

            Stopwatch stopwatch = new Stopwatch();

            stopwatch.Start();

            //Parallel.For(0, 7, (int i) => { Thread.Sleep(1000); d *= (i + 1); });
            for (int i = 0; i <= 7; i++)
            {
                Thread.Sleep(1000); d *= (i + 1);
            }

            stopwatch.Stop();

            Console.WriteLine("Time elapsed: {0}", stopwatch.Elapsed);
        }
    }
}