In this task, you are given an input list A comprising of numbers and alphabets. You need to extract and sort the unique alphabets in the list. The alphabets in the input list will only be in lowercase. Return -1 if there is no alphabet in the input list.

[EX Q]: ['4945', 'i', 'h', 's', '8925', 'i', '3995', 'f', '813', '1823', '3475', 'q', '2463', '9487', 'c', 'c', 'n', 'y', 's', '6269', 'a', 'u', 'd', 'd', '9291', '3187', '545', '7929', 'd', '1007', '7579', '8421', '4033', 'v', 'c', 'e', 'n', 'j']
[EX A]: a, c, d, e, f, h, i, j, n, q, s, u, v, y

[EX Q]: ['8739', 'v', 'm', '6277', 'l', 's', '109', '8057', '3835', 'd', 'u', 'f', 'w', 'd', 'p', '7705', '3643', '4455', 'u', 'p', 'u', '9407', 'g', 'w', '595', 'z', '6827', '6879', 'w', 'w', '6973', 'm', 'e', '1553', 'v', '3529', '8953', '3903', '5713', '8249', 'e', '1113', 'b', 't', 'r']
[EX A]: b, d, e, f, g, l, m, p, r, s, t, u, v, w, z

[EX Q]: ['o', 'e', 'q', '2953', 'u', '4279', '1695', '5105', '3265', 'e', '4111', '3969', '9597', 'e', '1259', '6063', 't', 't', '4795', '1615', 'j']
[EX A]:
e, j, o, q, t, u