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.

[Q]: ['6709', 't', 'n', 'k', '991', 'a', '8899', '3563', '527', 'm', '4599', '6679', 'm', 'x', 'f', 'o', '3275', 'x', '677', 'b', '3329', '3593', '5183', '5753', 'u', '6045', '2607', 'y', '9873']
[A]: a, b, f, k, m, n, o, t, u, x, y


[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']
[A]: a, c, d, e, f, h, i, j, n, q, s, u, v, y


[Q]: ['s', 'n', 'f', 'o', '2517', 'e', '3351', '6295', '507', 'e', 'h', '3099', 'w', '785', 'k', 'v', 'a', 'x', '7781', '9353', 'g', 'u', 'b']
[A]:
a, b, e, f, g, h, k, n, o, s, u, v, w, x