WORST_CASE(?,O(n^1))

Solution:
---------

  ++ :: [A(12) x A(12)] -(12)-> A(12)
  ++ :: [A(2) x A(2)] -(2)-> A(2)
  ++ :: [A(0) x A(0)] -(0)-> A(0)
  ++ :: [A(3) x A(3)] -(3)-> A(3)
  merge :: [A(12) x A(2)] -(1)-> A(0)
  nil :: [] -(0)-> A(2)
  nil :: [] -(0)-> A(12)
  u :: [] -(0)-> A(2)
  u :: [] -(0)-> A(13)
  u :: [] -(0)-> A(12)
  v :: [] -(0)-> A(2)
  v :: [] -(0)-> A(13)
  v :: [] -(0)-> A(4)


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

  ++ :: [A_cf(0) x A_cf(0)] -(0)-> A_cf(0)
  merge :: [A_cf(0) x A_cf(0)] -(0)-> A_cf(0)
  nil :: [] -(0)-> A_cf(0)
  u :: [] -(0)-> A_cf(0)
  v :: [] -(0)-> A_cf(0)


Base Constructors:
------------------
  ++_A :: [A(0) x A(0)] -(0)-> A(0)
  nil_A :: [] -(0)-> A(1)
  u_A :: [] -(0)-> A(1)
  v_A :: [] -(0)-> A(1)