using recursion

using System;
using System.Collections.Generic;
//Write a program that fills and prints a matrix of size (n, n) as shown below: (examples for n = 4)
// 1 12 11 10
// 2 13 16 9
// 3 14 15 8
// 4 5  6  7

class Program
{
    static int n = 9; //matriz size
    static int[,] matrix = new int[n, n];
    static int score = 1;
    static void Main()
    {

        int pos = 0;
        Recursion(pos);

        print(matrix);
    }


    private static void Recursion(int pos)
    {
        if(pos >= n/2 + 1) //bottom
        {
            return;
        }
        int x;
        int y;
        for (x = pos,y = pos; x< n - pos;x++)
        {
            matrix[x,y] = score++;
        }
        x--;
        for (y = y + 1 ;y < n - pos; y++)
        {
            matrix[x, y] = score++;
        }
        y--;
        for (x = x - 1; x >= 0 + pos; x--)
        {
            matrix[x, y] = score++;
        }
        x++;
        for (y = y - 1; y > 0 + pos; y--)
        {
            matrix[x, y] = score++;
        }

        Recursion(pos + 1); //recursive call

    }


    private static void print(int[,] matrix)
    {
        for (int x = 0; x < matrix.GetLength(0); x++)
        {
            for (int y = 0; y < matrix.GetLength(1); y++)
            {
                if (matrix[x, y] < 10)
                {
                    Console.Write(" "+matrix[x, y]);
                }
                else
                {
                    Console.Write(matrix[x, y]);
                }

            }
            Console.WriteLine();
        }
    }
}