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:
    {  test(x_0, y) -> True()
     , test(x_0, y) -> False()
     , append(l1_2, l2_1) -> match_0(l1_2, l2_1, l1_2)
     , match_0(l1_2, l2_1, Nil()) -> l2_1
     , match_0(l1_2, l2_1, Cons(x, l)) -> Cons(x, append(l, l2_1))
     , part(a_4, l_3) -> match_1(a_4, l_3, l_3)
     , match_1(a_4, l_3, Nil()) -> Pair(Nil(), Nil())
     , match_1(a_4, l_3, Cons(x, l')) ->
       match_2(x, l', a_4, l_3, part(a_4, l'))
     , match_2(x, l', a_4, l_3, Pair(l1, l2)) ->
       match_3(l1, l2, x, l', a_4, l_3, test(a_4, x))
     , match_3(l1, l2, x, l', a_4, l_3, False()) ->
       Pair(Cons(x, l1), l2)
     , match_3(l1, l2, x, l', a_4, l_3, True()) -> Pair(l1, Cons(x, l2))
     , quick(l_5) -> match_4(l_5, l_5)
     , match_4(l_5, Nil()) -> Nil()
     , match_4(l_5, Cons(a, l')) -> match_5(a, l', l_5, part(a, l'))
     , match_5(a, l', l_5, Pair(l1, l2)) ->
       append(quick(l1), Cons(a, quick(l2)))}

Proof Output:    
  The input cannot be shown compatible