MAYBE
MAYBE
TRS:
 {
  sel(s(N), cons(X)) -> sel(N, XS),
   sel(0(), cons(X)) -> X,
          fib1(X, Y) -> cons(X),
              fib(N) -> sel(N, fib1(s(0()), s(0()))),
        add(s(X), Y) -> s(add(X, Y)),
         add(0(), X) -> X
 }
 DUP: We consider a duplicating system.
  Trs:
   {
    sel(s(N), cons(X)) -> sel(N, XS),
     sel(0(), cons(X)) -> X,
            fib1(X, Y) -> cons(X),
                fib(N) -> sel(N, fib1(s(0()), s(0()))),
          add(s(X), Y) -> s(add(X, Y)),
           add(0(), X) -> X
   }
  Fail