MAYBE
MAYBE
TRS:
 {
  sel(s(N), cons(X, XS)) -> sel(N, XS),
   sel(0(), cons(X, XS)) -> X,
              fib1(X, Y) -> cons(X, fib1(Y, add(X, Y))),
                  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, XS)) -> sel(N, XS),
     sel(0(), cons(X, XS)) -> X,
                fib1(X, Y) -> cons(X, fib1(Y, add(X, Y))),
                    fib(N) -> sel(N, fib1(s(0()), s(0()))),
              add(s(X), Y) -> s(add(X, Y)),
               add(0(), X) -> X
   }
  Fail