using System;

class SpiralMatrix
{
    public static void Main()
    {
        //Initiate a variable for the size of the matrix
        int n;

        //User input
        Console.Write("Input an integer number in the interval [1;19]: ");

        //A variable to check for valid input
        bool valid = Int32.TryParse(Console.ReadLine(), out n);

        //Input validation
        if (valid && (n > 0 && n < 20))
        {
            //Initiation of the matrix
            int[,] num = new int[n, n];

            //Initiation of coordinates and direction
            int x = 0, y = 0, direction = 0;

            //For-loop for filling up the matrix
            for (int i = 0; i < n * n; i++)
            {

                //Write on a particular position in the matrix the value of the counter of the for-loop. The starting position is (0,0) and the first value is 1.
                num[x, y] = i + 1;

                //Depending on the direction of movement there are 4 different cases.
                switch (direction)
                {
                    //Direction down
                    case 0:
                        //If x is lower the the maxXBound and the position is empty increase x by 1 and start the loop again. This will continue until row 1 is full
                        if (x < n - 1 && num[x + 1, y] == 0)
                        {
                            x++;
                        }
                        //When row 1 is full the direction changes:
                        else
                        {
                            direction = (++direction) % 4;
                            y++;
                        }
                        break;

                    //Direction right
                    case 1:
                        if (y < n - 1 && num[x, y + 1] == 0)
                        {
                            y++;
                        }
                        else
                        {
                            direction = (++direction) % 4;
                            x--;
                        }
                        break;

                    //Direction up
                    case 2:
                        if (x > 0 && num[x - 1, y] == 0)
                        {
                            x--;
                        }
                        else
                        {
                            direction = (++direction) % 4;
                            y--;
                        }
                        break;

                    //Direction left
                    case 3:
                        if (y > 0 && num[x, y - 1] == 0)
                        {
                            y--;
                        }
                        else
                        {
                            direction = (++direction) % 4;
                            x++;
                        }
                        break;
                    default:
                        Console.WriteLine("Invalid direction value!");
                        break;
                }
            }
            int align = ((n * n).ToString()).Length;
            for (int i = 0; i < n; i++)
            {
                for (int j = 0; j < n; j++)
                {
                    Console.Write("{0}", ((num[j, i].ToString()).PadRight(align / 2)).PadLeft(align + 1));
                }
                Console.WriteLine();
            }
        }
        else
        {
            Console.WriteLine("Invalid input data!");
        }
    }
}