WORST_CASE(?,O(n^1))

Solution:
---------

  0 :: [] -(0)-> a(14)
  p :: [a(14) x a(14) x a(14)] -(2)-> a(0)
  s :: [a(14)] -(14)-> a(14)


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

  0 :: [] -(0)-> a_cf(0)
  p :: [a_cf(0) x a_cf(0) x 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)