YES(?,ELEMENTARY)

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

Proof Output:    
  Strict Rules in Predicative Notation:
   {  bin(x; 0()) -> s(; 0())
    , bin(0(); s(; y)) -> 0()
    , bin(s(; x); s(; y)) -> +(; bin(x; s(; y)), bin(x; y))}
  Safe Mapping:
   safe(bin) = {2}, safe(0) = {}, safe(s) = {1}, safe(+) = {1, 2}
  Argument Permutation:
   mu(bin) = [2, 1]
  Precedence:
   bin ~ bin