/* Type your answer here, the click "Share" and copy the link. 

 * Answer: The simplist answer here is that this 'randomizes' a 2D array by first getting a random index for both i & j then storing the current value of array[i,j] in a temp variable. To which the value of the randomly selected index is stored back into

 * the current index and then the random index'd array gets the current indexs value. The use case for this could be to randomize id's for some use or to alter the function from an int[] to a List<T> to which you could store objects and other more 

 * complex items to randomize.

*/

​

​

using System;

public class Program

{

    private static int[,] array = new int [13, 4];

    // inspecting the method below, what might this alorithm be used for?

    public static void Main()

    {

        var rand = new Random();

        // assume 'array' is already initialized with appropritate values.

        for (int i = 0; i < 4; i++)

        {

            for (int j = 12; j > 0; j--)

            {

                var randi = rand.Next(0, 4);

                var randj = rand.Next(0, 12);

                var hold = array[j, i];

                array[j, i] = array[randj, randi];

                array[randj, randi] = hold;

            }

        }

        return;

    }

}