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:
    {  eq(0(), 0()) -> true()
     , eq(0(), s(x)) -> false()
     , eq(s(x), 0()) -> false()
     , eq(s(x), s(y)) -> eq(x, y)
     , or(true(), y) -> true()
     , or(false(), y) -> y
     , union(empty(), h) -> h
     , union(edge(x, y, i), h) -> edge(x, y, union(i, h))
     , isEmpty(empty()) -> true()
     , isEmpty(edge(x, y, i)) -> false()
     , from(edge(x, y, i)) -> x
     , to(edge(x, y, i)) -> y
     , rest(edge(x, y, i)) -> i
     , rest(empty()) -> empty()
     , reach(x, y, i, h) ->
       if1(eq(x, y), isEmpty(i), eq(x, from(i)), eq(y, to(i)), x, y, i, h)
     , if1(true(), b1, b2, b3, x, y, i, h) -> true()
     , if1(false(), b1, b2, b3, x, y, i, h) ->
       if2(b1, b2, b3, x, y, i, h)
     , if2(true(), b2, b3, x, y, i, h) -> false()
     , if2(false(), b2, b3, x, y, i, h) -> if3(b2, b3, x, y, i, h)
     , if3(false(), b3, x, y, i, h) ->
       reach(x, y, rest(i), edge(from(i), to(i), h))
     , if3(true(), b3, x, y, i, h) -> if4(b3, x, y, i, h)
     , if4(true(), x, y, i, h) -> true()
     , if4(false(), x, y, i, h) ->
       or(reach(x, y, rest(i), h),
          reach(to(i), y, union(rest(i), h), empty()))}

Proof Output:    
  The input cannot be shown compatible