Input TRS:
    1: a__zeros() -> cons(0(),zeros())
    2: a__and(tt(),X) -> mark(X)
    3: a__length(nil()) -> 0()
    4: a__length(cons(N,L)) -> s(a__length(mark(L)))
    5: mark(zeros()) -> a__zeros()
    6: mark(and(X1,X2)) -> a__and(mark(X1),X2)
    7: mark(length(X)) -> a__length(mark(X))
    8: mark(cons(X1,X2)) -> cons(mark(X1),X2)
    9: mark(0()) -> 0()
    10: mark(tt()) -> tt()
    11: mark(nil()) -> nil()
    12: mark(s(X)) -> s(mark(X))
    13: a__zeros() -> zeros()
    14: a__and(X1,X2) -> and(X1,X2)
    15: a__length(X) -> length(X)
Number of Rules: 15
Direct QKBOS(Sum) ... failed.