[Ask] Expandable Banner - PHP

[xrvel]

There are 4 banner spaces :

[A]  [B]  [C]  [D]

Usual banner only takes 1 space.
But i want the user to order more than 1 space and expandable.
For example if user chooses [A] position, he /she can expand the banner into (for example) 2 spaces

[   A   ]  [C]  [D]

And if user chooses position, he / she can expand the banner into (for example) 2 spaces

[A]  [   B     ] [D]

If he / she chooses and expands 3 spaces

[A]  [        B      ]

In my current code, i store "expand" in my database. For example if "expand" column is 1, banner will take 1 more space.

Space only can be expanded in right direction.

Anyone knows the algorithm?

Thanks.
Kurniawan.