MAYBE

'epo* (timeout of 60.0 seconds)'
--------------------------------
Answer:           MAYBE
Input Problem:    innermost runtime-complexity with respect to
  Rules:
    {  fib(0()) -> 0()
     , fib(s(0())) -> s(0())
     , fib(s(s(0()))) -> s(0())
     , fib(s(s(x))) -> sp(g(x))
     , g(0()) -> pair(s(0()), 0())
     , g(s(0())) -> pair(s(0()), s(0()))
     , g(s(x)) -> np(g(x))
     , sp(pair(x, y)) -> +(x, y)
     , np(pair(x, y)) -> pair(+(x, y), x)
     , +(x, 0()) -> x
     , +(x, s(y)) -> s(+(x, y))}

Proof Output:    
  The input cannot be shown compatible