Game->LItem[];

int LItems[]
* The level items of level i currently under the posession of the player,
* where i is the index used to access this array. Each element of this
* array consists of flags ORed (|) together; use the LI_ constants in
* std.zh to set or compare these values.

How do I use this?

Edit:
Right, so it uses binary.
And to check whether Link has the compass, I do something like this:

	int cmp = 0100b;
	int curitems = Game->LItems[lvnum];
	int chk = cmp & curitems;
	if(chk == 0100b){

However, apparently the Boss Key item is '16' in std.zh.
How am I supposed to express 16 in a 4-bit byte?
This is illogical.