WORST_CASE(?,O(n^1))

Solution:
---------

  cons :: [a(0) x b(2)] -(2)-> b(2)
  cons :: [a(0) x b(1)] -(1)-> b(1)
  cons :: [a(0) x b(0)] -(0)-> b(0)
  empty :: [] -(0)-> b(2)
  empty :: [] -(0)-> b(1)
  empty :: [] -(0)-> b(0)
  f :: [b(1) x b(2)] -(2)-> b(0)
  g :: [b(1) x b(0)] -(1)-> b(0)


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

  cons :: [a_cf(0) x b_cf(0)] -(0)-> b_cf(0)
  empty :: [] -(0)-> b_cf(0)
  f :: [b_cf(0) x b_cf(0)] -(0)-> b_cf(0)
  g :: [b_cf(0) x b_cf(0)] -(0)-> b_cf(0)