TRS: { a__from(X) -> cons(mark(X), from(s(X))), a__length(nil()) -> 0(), a__length(cons(X, Y)) -> s(a__length1(Y)), a__length1(X) -> a__length(X), mark(from(X)) -> a__from(mark(X)), mark(length(X)) -> a__length(X), mark(length1(X)) -> a__length1(X), mark(cons(X1, X2)) -> cons(mark(X1), X2), mark(s(X)) -> s(mark(X)), mark(nil()) -> nil(), mark(0()) -> 0(), a__from(X) -> from(X), a__length(X) -> length(X), a__length1(X) -> length1(X)} Fail