YES(?,POLY)

'Pop* (timeout of 60.0 seconds)'
--------------------------------
Answer:           YES(?,POLY)
Input Problem:    innermost runtime-complexity with respect to
  Rules:
    {  +(0(), y) -> y
     , +(s(x), y) -> s(+(x, y))
     , -(0(), y) -> 0()
     , -(x, 0()) -> x
     , -(s(x), s(y)) -> -(x, y)}

Proof Output:    
  The input was oriented with the instance of POP* as induced by the precedence
  
   + ~ -
  
  and safe mapping
  
   safe(+) = {2}, safe(0) = {}, safe(s) = {1}, safe(-) = {} .
  
  For your convenience, here is the input in predicative notation:
  
   Rules:
    {  +(0(); y) -> y
     , +(s(; x); y) -> s(; +(x; y))
     , -(0(), y;) -> 0()
     , -(x, 0();) -> x
     , -(s(; x), s(; y);) -> -(x, y;)}