WORST_CASE(?,O(n^1))

Solution:
---------

  + :: [A(1) x A(2)] -(1)-> A(0)
  0 :: [] -(0)-> A(8)
  0 :: [] -(0)-> A(2)
  0 :: [] -(0)-> A(6)
  double :: [A(8)] -(4)-> A(0)
  s :: [A(8)] -(8)-> A(8)
  s :: [A(2)] -(2)-> A(2)
  s :: [A(1)] -(1)-> A(1)
  s :: [A(0)] -(0)-> A(0)


Cost Free Signatures:
---------------------

  + :: [A_cf(0) x A_cf(0)] -(0)-> A_cf(0)
  0 :: [] -(0)-> A_cf(0)
  double :: [A_cf(0)] -(0)-> A_cf(0)
  s :: [A_cf(0)] -(0)-> A_cf(0)


Base Constructors:
------------------
  0_A :: [] -(0)-> A(1)
  s_A :: [A(1)] -(1)-> A(1)