MAYBE
* Step 1: Failure MAYBE
  + Considered Problem:
      - Strict TRS:
          append(l1,l2) -> ifappend(l1,l2,is_empty(l1))
          hd(cons(x,l)) -> x
          ifappend(l1,l2,false()) -> cons(hd(l1),append(tl(l1),l2))
          ifappend(l1,l2,true()) -> l2
          is_empty(cons(x,l)) -> false()
          is_empty(nil()) -> true()
          tl(cons(x,l)) -> cons(x,l)
      - Signature:
          {append/2,hd/1,ifappend/3,is_empty/1,tl/1} / {cons/2,false/0,nil/0,true/0}
      - Obligation:
          innermost runtime complexity wrt. defined symbols {append,hd,ifappend,is_empty,tl} and constructors {cons
          ,false,nil,true}
  + Applied Processor:
      MI {miKind = Automaton Nothing, miDimension = 3, miUArgs = NoUArgs, miURules = NoURules, miSelector = Nothing}
  + Details:
      Incompatible
MAYBE