MAYBE

'Pop* with parameter subtitution (timeout of 60.0 seconds)'
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Answer:           MAYBE
Input Problem:    innermost runtime-complexity with respect to
  Rules:
    {  +(0(), y) -> y
     , +(s(x), y) -> s(+(x, y))
     , *(x, 0()) -> 0()
     , *(x, s(y)) -> +(x, *(x, y))
     , twice(0()) -> 0()
     , twice(s(x)) -> s(s(twice(x)))
     , -(x, 0()) -> x
     , -(s(x), s(y)) -> -(x, y)
     , f(s(x)) ->
       f(-(*(s(s(x)), s(s(x))), +(*(s(x), s(s(x))), s(s(0())))))}

Proof Output:    
  The input cannot be shown compatible