MAYBE
* Step 1: Failure MAYBE
  + Considered Problem:
      - Strict TRS:
          app(add(n,x),y) -> add(n,app(x,y))
          app(nil(),y) -> y
          head(add(n,x)) -> n
          if(false(),x,y,z) -> shuff(reverse(tail(x)),z)
          if(true(),x,y,z) -> y
          null(add(n,x)) -> false()
          null(nil()) -> true()
          reverse(add(n,x)) -> app(reverse(x),add(n,nil()))
          reverse(nil()) -> nil()
          shuff(x,y) -> if(null(x),x,y,app(y,add(head(x),nil())))
          shuffle(x) -> shuff(x,nil())
          tail(add(n,x)) -> x
          tail(nil()) -> nil()
      - Signature:
          {app/2,head/1,if/4,null/1,reverse/1,shuff/2,shuffle/1,tail/1} / {add/2,false/0,nil/0,true/0}
      - Obligation:
          innermost runtime complexity wrt. defined symbols {app,head,if,null,reverse,shuff,shuffle
          ,tail} and constructors {add,false,nil,true}
  + Applied Processor:
      EmptyProcessor
  + Details:
      The problem is still open.
MAYBE