What will be the output of the following C# code?

static void Main(string[] args)
{
    int i, j;
    int[, ] arr = new int[ 3, 3];
    for (i = 0; i < 3; ++i)
    {
        for (j = 0; j < 3; ++j)
        {
            arr[i, j] = i * 2 + i * 2;
            Console.WriteLine(arr[i, j]);
        }
        Console.ReadLine();
    }
}