Thread: two dimensional array initialization

I have used following array initialization in my code.

Code:

static const int a[][] = { {2, -5, 7},
                                  {4, 8, -2},
                                  {7, 24, 78} };

But it is giving following error during compilation.

error: array type has incomplete element type

I think we can omit the array size if we are initializing the array.
Can you please tell me why it is giving the compilation error.