MAYBE
* Step 1: Failure MAYBE
  + Considered Problem:
      - Strict TRS:
          a__adx(X) -> adx(X)
          a__adx(cons(X,Y)) -> a__incr(cons(X,adx(Y)))
          a__hd(X) -> hd(X)
          a__hd(cons(X,Y)) -> mark(X)
          a__incr(X) -> incr(X)
          a__incr(cons(X,Y)) -> cons(s(X),incr(Y))
          a__nats() -> a__adx(a__zeros())
          a__nats() -> nats()
          a__tl(X) -> tl(X)
          a__tl(cons(X,Y)) -> mark(Y)
          a__zeros() -> cons(0(),zeros())
          a__zeros() -> zeros()
          mark(0()) -> 0()
          mark(adx(X)) -> a__adx(mark(X))
          mark(cons(X1,X2)) -> cons(X1,X2)
          mark(hd(X)) -> a__hd(mark(X))
          mark(incr(X)) -> a__incr(mark(X))
          mark(nats()) -> a__nats()
          mark(s(X)) -> s(X)
          mark(tl(X)) -> a__tl(mark(X))
          mark(zeros()) -> a__zeros()
      - Signature:
          {a__adx/1,a__hd/1,a__incr/1,a__nats/0,a__tl/1,a__zeros/0,mark/1} / {0/0,adx/1,cons/2,hd/1,incr/1,nats/0,s/1
          ,tl/1,zeros/0}
      - Obligation:
          innermost runtime complexity wrt. defined symbols {a__adx,a__hd,a__incr,a__nats,a__tl,a__zeros
          ,mark} and constructors {0,adx,cons,hd,incr,nats,s,tl,zeros}
  + Applied Processor:
      NaturalPI {shape = Mixed 3, restrict = NoRestrict, uargs = UArgs, urules = URules, selector = Nothing}
  + Details:
      Incompatible
MAYBE