Question

int numbs[4][4] = 
     1,  2,  3,  4
     5,  6,  7,  8
     9, 10, 11, 12
    13, 14, 15, 16;

When i print it, it should print like this.

1 2 3 4, 8, 12,16, 15, 14, 13, 9, 5, 6, 7, 11, 10, (ie clockwise direction spiral):

---\ //first right, then down, left, up and repeat
/-\|
|-/|
\--/

Answer 1

Here’s my stab at it:

    static void Spiral(int[,] m)
    {
        int n = m.GetUpperBound(0);
        for (int i = 0; i < n / 2; ++i)
        {
            for (int j = i; j <= n - i; ++j)
                Console.Write(m[i, j] + " ");
            for (int j = i + 1; j <= n - i; ++j)
                Console.Write(m[j, n - i] + " ");
            for (int j = i + 1; j <= n - i; ++j)
                Console.Write(m[n - i, n - j] + " ");
            for (int j = i + 1; j < n - i; ++j)
                Console.Write(m[n - j, i] + " ");
        }

        Console.Write(m[n / 2, n / 2]+" ");
        if (n % 2 == 1)
        {
            Console.Write(m[n / 2, n / 2+1] + " ");
            Console.Write(m[n / 2+1, n / 2+1] + " ");
            Console.Write(m[n / 2+1, n / 2] + " ");
        }
    }

    static void Main(string[] args)
    {
        int[,] myArray = new int[,]{
            {11, 12, 13, 14, 15},
            {21, 22, 23, 24, 25},
            {31, 32, 33, 34, 35},
            {41, 42, 43, 44, 45},
            {51, 52, 53, 54, 55}
        };
        Spiral(myArray);
    }

The output is:

11 12 13 14 15 25 35 45 55 54 53 52 51 41 31 21 22 23 24 34 44 43 42 32 33

edit: Works for both even and odd sized square matrices now.