MAYBE
* Step 1: Failure MAYBE
  + Considered Problem:
      - Strict TRS:
          0() -> n__0()
          U11(tt(),V2) -> U12(isNat(activate(V2)))
          U12(tt()) -> tt()
          U21(tt()) -> tt()
          U31(tt(),V2) -> U32(isNat(activate(V2)))
          U32(tt()) -> tt()
          U41(tt(),N) -> activate(N)
          U51(tt(),M,N) -> U52(isNat(activate(N)),activate(M),activate(N))
          U52(tt(),M,N) -> s(plus(activate(N),activate(M)))
          U61(tt()) -> 0()
          U71(tt(),M,N) -> U72(isNat(activate(N)),activate(M),activate(N))
          U72(tt(),M,N) -> plus(x(activate(N),activate(M)),activate(N))
          activate(X) -> X
          activate(n__0()) -> 0()
          activate(n__plus(X1,X2)) -> plus(activate(X1),activate(X2))
          activate(n__s(X)) -> s(activate(X))
          activate(n__x(X1,X2)) -> x(activate(X1),activate(X2))
          isNat(n__0()) -> tt()
          isNat(n__plus(V1,V2)) -> U11(isNat(activate(V1)),activate(V2))
          isNat(n__s(V1)) -> U21(isNat(activate(V1)))
          isNat(n__x(V1,V2)) -> U31(isNat(activate(V1)),activate(V2))
          plus(N,0()) -> U41(isNat(N),N)
          plus(N,s(M)) -> U51(isNat(M),M,N)
          plus(X1,X2) -> n__plus(X1,X2)
          s(X) -> n__s(X)
          x(N,0()) -> U61(isNat(N))
          x(N,s(M)) -> U71(isNat(M),M,N)
          x(X1,X2) -> n__x(X1,X2)
      - Signature:
          {0/0,U11/2,U12/1,U21/1,U31/2,U32/1,U41/2,U51/3,U52/3,U61/1,U71/3,U72/3,activate/1,isNat/1,plus/2,s/1
          ,x/2} / {n__0/0,n__plus/2,n__s/1,n__x/2,tt/0}
      - Obligation:
          innermost runtime complexity wrt. defined symbols {0,U11,U12,U21,U31,U32,U41,U51,U52,U61,U71,U72,activate
          ,isNat,plus,s,x} and constructors {n__0,n__plus,n__s,n__x,tt}
  + Applied Processor:
      MI {miKind = Automaton Nothing, miDimension = 3, miUArgs = NoUArgs, miURules = NoURules, miSelector = Nothing}
  + Details:
      Incompatible
MAYBE