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

public class Test
{
    static string[][] GetRandomJaggedArray(int numberOfArrays, int numberOfElements)
    {
        string[][] temp = new string[numberOfArrays][];
        for (int i = 0; i < numberOfArrays; i++)
        {
           temp[i] = new string[numberOfElements];
           for (int i2 = 0; i2 < temp.Length; i2++)
               temp[i][i2] = Guid.NewGuid().ToString();                                                                                              
        }

        return temp;
    }

    static TimeSpan getElementsAtIndexLINQ(string[][] listOfArrays, int index, int count)
    {
        Stopwatch s  = new Stopwatch(); 
        List<string> myListOfStrings;

        s.Start();
        for (int i = 0; i < count; i++)            
            myListOfStrings = listOfArrays.Select(a => a[index]).ToList();            
        s.Stop();
        return s.Elapsed;
    }

    static TimeSpan getElementsAtIndexFOR(string[][] listOfArrays, int index, int count)
    {
        Stopwatch s = new Stopwatch();
        s.Start();
        for (int i2 = 0; i2 < count; i2++ ) {
        	List<string> myListOfStrings = new List<string>();
            for (int i = 0; i < listOfArrays.Length; i++)
                myListOfStrings.Add(listOfArrays[i][index]);
        }
        s.Stop();
        return s.Elapsed;
    }

    static void Main(string[] args)
    {
        string[][] test1 = GetRandomJaggedArray(100, 1000);

        string[][] test2 = GetRandomJaggedArray(100, 1000);

getElementsAtIndexFOR(test2, 1, 1);

        TimeSpan t2 = getElementsAtIndexFOR(test2, 1, 10);

getElementsAtIndexLINQ(test1, 1, 1);
        TimeSpan t1 = getElementsAtIndexLINQ(test1, 1, 10);

        Console.WriteLine("Linq method took {0} ticks to execute", t1.Ticks);

        Console.WriteLine("For method took {0} ticks to execute", t2.Ticks);

    }
}