Input TRS:
    1: active(f(0())) -> mark(cons(0(),f(s(0()))))
    2: active(f(s(0()))) -> mark(f(p(s(0()))))
    3: active(p(s(0()))) -> mark(0())
    4: mark(f(X)) -> active(f(mark(X)))
    5: mark(0()) -> active(0())
    6: mark(cons(X1,X2)) -> active(cons(mark(X1),X2))
    7: mark(s(X)) -> active(s(mark(X)))
    8: mark(p(X)) -> active(p(mark(X)))
    9: f(mark(X)) -> f(X)
    10: f(active(X)) -> f(X)
    11: cons(mark(X1),X2) -> cons(X1,X2)
    12: cons(X1,mark(X2)) -> cons(X1,X2)
    13: cons(active(X1),X2) -> cons(X1,X2)
    14: cons(X1,active(X2)) -> cons(X1,X2)
    15: s(mark(X)) -> s(X)
    16: s(active(X)) -> s(X)
    17: p(mark(X)) -> p(X)
    18: p(active(X)) -> p(X)
Number of Rules: 18
Direct QWPOS(Pol) ... failed.