shapes(Matrix,N) :-
	transform(Matrix,[],Matrix1),
	numbervars(Matrix1,0,N).

transform([],_,[]).
transform([Line|RestMatrix],PrevLine,[Line1|RestMatrix1]) :-
	new_neighbor(PrevLine,P1,PrevLine1),
	new_neighbor(PrevLine1,P2,PrevLine2),
	transformline(Line,black,P1,P2,PrevLine2,white(_),Line1),
	transform(RestMatrix,Line1,RestMatrix1).

transformline([],_,_,_,_,_,[]).
transformline([black|Xs],_,P1,P2,RP,_,[black|Ys]) :-
	new_neighbor(RP,P3,RestRP),
	transformline(Xs,P1,P2,P3,RestRP,white(_),Ys).
transformline([white|Xs],P0,P1,P2,RP,WhiteVar,[WhiteVar|Ys]) :-
	new_neighbor(RP,P3,RestRP),
	bind(P0,WhiteVar),
	bind(P1,WhiteVar),
	bind(P2,WhiteVar),
	transformline(Xs,P1,P2,P3,RestRP,WhiteVar,Ys).

bind(black,_).
bind(white(V),white(V)).

new_neighbor([],black,[]).
new_neighbor([X|R],X,R).