using System;

​

public class Program

{

    public static void Main()

    {

        PrintMatrix(CircleMatrix(1));

        PrintMatrix(CircleMatrix(2));

        PrintMatrix(CircleMatrix(3));

    }

​

    private static void PrintMatrix(int[, ] matrix)

    {

        for (int row = 0; row <= matrix.GetUpperBound(0); row++)

        {

            for (int column = 0; column <= matrix.GetUpperBound(1); column++)

            {

                Console.Write(matrix[row, column] + " ");

            }

​

            Console.WriteLine();

        }

        Console.WriteLine();

    }

​

    // TODO: write this algorithmically - i.e. don't hardcode it

    public static int[, ] CircleMatrix(int n)

    {

        var matrix = new int[n, n];

        if (n <= 0)

            throw new NotImplementedException();

        else if (n == 1)

            matrix = new int[1, 1]{{1}};

        else if (n == 2)

        {

            matrix = new int[2, 2]{{1, 2}, {4, 3}};

        }

        else if (n == 3)

        {

            matrix = new int[3, 3]{{1, 2, 3}, {8, 9, 4}, {7, 6, 5}};

        }

        else

            throw new NotImplementedException();

        return matrix;

    }

}