TRS:
 { double(0()) -> 0(),
  double(s(x)) -> s(s(double(x))),
     +(x, 0()) -> x,
    +(x, s(y)) -> s(+(x, y)),
    +(s(x), y) -> s(+(x, y)),
     double(x) -> +(x, x)}
 Cdiprover:
  Interpretation class: pizerosimplemixed
  Complexity bound: POLYTIME COMPUTABLE
  +(X3, X2) = + 2*X3^2 + 0*X2^2 + 1*X3 + 0 + 2*X2 + 0*X2*X3
  s(X1) = + 1*X1 + 1
  double(X0) = + 2*X0^2 + 2 + 3*X0
  0 = + 1
  
  Qed