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]: ['4857', 'z', '313', '7813', '9935', 'o', 'w', 'i', 'x', 'o', 'e', 's', 'a', 'p', 'i', 'v', 'x', '6743', 'p', '435', 'u', 'a', 'h', '607', '2491', '6159', 'u', '7761', '6197', '3449', '3459', 'e', 'g', '8731', '335', '2883', '3941', 'n', '1881', 'y', 'j', '8189', 'k', '7593', '2747']
[EX A]: a, e, g, h, i, j, k, n, o, p, s, u, v, w, x, y, z

[EX Q]: ['789', '3603', '3517', '5831', 'z', 'q', 'w', 'l', '5701', '9503', '8169', '1123', 'e', '529', 'j', 'z', 'l', 'o', '3705', 'o', '5131', '6063', 'c', 'j', '6275', '7701']
[EX A]: c, e, j, l, o, q, w, z

[EX Q]: ['w', '6013', '8705', '6277', 'i', 'y', '8679', 'o', 'x', '3667', '4067', 'v', 'q', 'n', 'g', 'k', '4077', 'b', 'g', '5509', '7961', '3033', 'f', 'c', '9083', '8805', 'f', '3531', 'n', '2479', '4811', '6503', '711', '4431']
[EX A]:
b, c, f, g, i, k, n, o, q, v, w, x, y