14 Numbers as spiral

using System;

class NumbersAsSpiral
{
    static void Main()
    {
        Console.Write("Input positive integer N (N<20)");
        byte n = byte.Parse(Console.ReadLine());
        int[,] array = new int[n, n];
        byte x = 0;
        byte y = 0;
        bool xUp = false;
        bool yUp = true;
        bool xDown = false;
        bool yDown = false;
        for (int i = 1; i <= n * n; i++)
        {
            array[x, y] = i;
            if (yUp && ((y + 1 >= n) || (array[x, y + 1] > 0)))
            {
                yUp = false;
                xUp = true;
            }
            if (xUp && ((x + 1 >= n) || (array[x + 1, y] > 0)))
            {
                xUp = false;
                yDown = true;
            }
            if (yDown && ((y == 0) || (array[x, y - 1] > 0)))
            {
                yDown = false;
                xDown = true;
            }
            if (xDown && ((x == 0) || (array[x - 1, y] > 0)))
            {
                xDown = false;
                yUp = true;
            }
            if (xUp)
            {
                x++;
            }
            if (xDown)
            {
                x--;
            }
            if (yUp)
            {
                y++;
            }
            if (yDown)
            {
                y--;
            }
        }
        printArray(array);
    }

    public static void printArray(int[,] array)
    {
        for (int i = 0; i < array.GetLength(0); i++)
        {
            for (int j = 0; j < array.GetLength(1); j++)
            {
                Console.Write("{0,4}",array[i,j]);
            }
            Console.WriteLine();
        }
    }
}