MAYBE
* Step 1: Failure MAYBE
  + Considered Problem:
      - Strict TRS:
          a__U11(X1,X2) -> U11(X1,X2)
          a__U11(tt(),L) -> a__U12(tt(),L)
          a__U12(X1,X2) -> U12(X1,X2)
          a__U12(tt(),L) -> s(a__length(mark(L)))
          a__U21(X1,X2,X3,X4) -> U21(X1,X2,X3,X4)
          a__U21(tt(),IL,M,N) -> a__U22(tt(),IL,M,N)
          a__U22(X1,X2,X3,X4) -> U22(X1,X2,X3,X4)
          a__U22(tt(),IL,M,N) -> a__U23(tt(),IL,M,N)
          a__U23(X1,X2,X3,X4) -> U23(X1,X2,X3,X4)
          a__U23(tt(),IL,M,N) -> cons(mark(N),take(M,IL))
          a__length(X) -> length(X)
          a__length(cons(N,L)) -> a__U11(tt(),L)
          a__length(nil()) -> 0()
          a__take(X1,X2) -> take(X1,X2)
          a__take(0(),IL) -> nil()
          a__take(s(M),cons(N,IL)) -> a__U21(tt(),IL,M,N)
          a__zeros() -> cons(0(),zeros())
          a__zeros() -> zeros()
          mark(0()) -> 0()
          mark(U11(X1,X2)) -> a__U11(mark(X1),X2)
          mark(U12(X1,X2)) -> a__U12(mark(X1),X2)
          mark(U21(X1,X2,X3,X4)) -> a__U21(mark(X1),X2,X3,X4)
          mark(U22(X1,X2,X3,X4)) -> a__U22(mark(X1),X2,X3,X4)
          mark(U23(X1,X2,X3,X4)) -> a__U23(mark(X1),X2,X3,X4)
          mark(cons(X1,X2)) -> cons(mark(X1),X2)
          mark(length(X)) -> a__length(mark(X))
          mark(nil()) -> nil()
          mark(s(X)) -> s(mark(X))
          mark(take(X1,X2)) -> a__take(mark(X1),mark(X2))
          mark(tt()) -> tt()
          mark(zeros()) -> a__zeros()
      - Signature:
          {a__U11/2,a__U12/2,a__U21/4,a__U22/4,a__U23/4,a__length/1,a__take/2,a__zeros/0,mark/1} / {0/0,U11/2,U12/2
          ,U21/4,U22/4,U23/4,cons/2,length/1,nil/0,s/1,take/2,tt/0,zeros/0}
      - Obligation:
          innermost runtime complexity wrt. defined symbols {a__U11,a__U12,a__U21,a__U22,a__U23,a__length,a__take
          ,a__zeros,mark} and constructors {0,U11,U12,U21,U22,U23,cons,length,nil,s,take,tt,zeros}
  + Applied Processor:
      NaturalPI {shape = Mixed 3, restrict = NoRestrict, uargs = UArgs, urules = URules, selector = Nothing}
  + Details:
      Incompatible
MAYBE