label(T,LT) :- label([],T,LT).
label(P,T,LT) :- T =.. [F|Args], labelAll(P,0,Args,LArgs), LT =.. [F,P|LArgs].

labelAll(_,_,[],[]).
labelAll(P,N,[X|Xs],[Y|Ys]) :-
	append(P,[N],PN), label(PN,X,Y), N1 is N+1, labelAll(P,N1,Xs,Ys).

append([],Ys,Ys).
append([X|Xs],Ys,[X|Zs]) :- append(Xs,Ys,Zs).


% | ?- label(f(a,g(b),h(a,b)),LT).
% LT = f([],a([0]),g([1],b([1,0])),h([2],a([2,0]),b([2,1]))) ? ;