How to dynamically allocate a struct containing multiple arrays?

Question

I'm trying to make a struct that contains another struct with multiple arrays. I need to dynamically allocate those arrays too, so I think I need another pointer still.

int arraysize;

typedef struct Array{
int *size = arraysize;
unsigned int val[*size];
unsigned int x[*size];
unsigned int y[*size];
} Array;

typedef struct Image{
int height;
int width;
int max;
Array *data;
} Image;

OK, so once I finally figure that out, I still need to figure out how to dynamically allocate that memory using malloc. I'm totally lost there too. Any help at all would be greatly appreciated.

EDIT: more clarification: I'm using the arrays to store three pieces of information that are all connected. Think of a chessboard, you could say knight E4, which tells you that on the 4th column of row E, there is a knight. If you started this process at A1 and ended at K10 you'd have a full chessboard right? The image struct is analogous to the chessboard, the Array is analogous to a list of a bunch of squares that compose the chessboard and the contents of those squares. (E.g. A1 null A2 knight a3 bishop etc...) Unfortunately, I don't know what kind of board will be passed through, it might be a 3x7 board or a 9x2 board etc. So I need to dynamically allocate the memory for those possibilities. Once I have the memory allocated I need to store information about the location and the contents of all of the "squares." Then I need to let a program pass through the height of the board, width of the board and the list of contents and I'd be done the hard part.

Answer 1

What you actually meant was:

typedef struct data {
    unsigned int x;
    unsigned int y;
    unsigned int val;
} Data;

typedef struct image {
    int height;
    int width;
    int max;
    Data* data;
} Image;

and somewhere:

Image i;
i.height = 10;
i.width  = 20;
i.data   = malloc(sizeof(Data) * i.width * i.height);
...
// one of the ways how to access Data at 2nd row, 3rd column:
*(i.data + i.width * 1 + 2).val = 7;
...
free(i.data);
i.data = NULL;

But what you actually need is some good book ;)