MAYBE
238.81/60.43	MAYBE
238.81/60.43	
238.81/60.43	Problem:
238.81/60.43	 active(zeros()) -> mark(cons(0(),zeros()))
238.81/60.43	 active(U11(tt(),L)) -> mark(U12(tt(),L))
238.81/60.43	 active(U12(tt(),L)) -> mark(s(length(L)))
238.81/60.43	 active(length(nil())) -> mark(0())
238.81/60.43	 active(length(cons(N,L))) -> mark(U11(tt(),L))
238.81/60.43	 active(cons(X1,X2)) -> cons(active(X1),X2)
238.81/60.43	 active(U11(X1,X2)) -> U11(active(X1),X2)
238.81/60.43	 active(U12(X1,X2)) -> U12(active(X1),X2)
238.81/60.43	 active(s(X)) -> s(active(X))
238.81/60.43	 active(length(X)) -> length(active(X))
238.81/60.43	 cons(mark(X1),X2) -> mark(cons(X1,X2))
238.81/60.43	 U11(mark(X1),X2) -> mark(U11(X1,X2))
238.81/60.43	 U12(mark(X1),X2) -> mark(U12(X1,X2))
238.81/60.43	 s(mark(X)) -> mark(s(X))
238.81/60.43	 length(mark(X)) -> mark(length(X))
238.81/60.43	 proper(zeros()) -> ok(zeros())
238.81/60.43	 proper(cons(X1,X2)) -> cons(proper(X1),proper(X2))
238.81/60.43	 proper(0()) -> ok(0())
238.81/60.43	 proper(U11(X1,X2)) -> U11(proper(X1),proper(X2))
238.81/60.43	 proper(tt()) -> ok(tt())
238.81/60.43	 proper(U12(X1,X2)) -> U12(proper(X1),proper(X2))
238.81/60.43	 proper(s(X)) -> s(proper(X))
238.81/60.43	 proper(length(X)) -> length(proper(X))
238.81/60.43	 proper(nil()) -> ok(nil())
238.81/60.43	 cons(ok(X1),ok(X2)) -> ok(cons(X1,X2))
238.81/60.43	 U11(ok(X1),ok(X2)) -> ok(U11(X1,X2))
238.81/60.43	 U12(ok(X1),ok(X2)) -> ok(U12(X1,X2))
238.81/60.43	 s(ok(X)) -> ok(s(X))
238.81/60.43	 length(ok(X)) -> ok(length(X))
238.81/60.43	 top(mark(X)) -> top(proper(X))
238.81/60.43	 top(ok(X)) -> top(active(X))
238.81/60.43	
238.81/60.43	Proof:
238.81/60.43	 Open
238.81/60.43	EOF