Measure

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;
using System.Threading;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            Stopwatch stopWatch = new Stopwatch();
            stopWatch.Start();
            int[,] arr = new int[10000, 10000];
            for (int i = 0; i < arr.GetLength(0); i++)
                for (int j = 0; j < arr.GetLength(1); j++)
                    arr[i, j] = ((i + 1) * j);
            for (int i = 0; i < arr.GetLength(0); i++)
                for (int j = 0; j < arr.GetLength(1); j++)
                    Console.Write(" {0}", arr[i, j]);
            stopWatch.Stop();
            TimeSpan ts = stopWatch.Elapsed;
            string elapsedTime = String.Format("{0:00}:{1:00}:{2:00}.{3:00}", ts.Hours, ts.Minutes, ts.Seconds, ts.Milliseconds / 10);
            Console.WriteLine("RunTime " + elapsedTime);
            Console.ReadKey();
        }
    }
}