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]: ['1971', 'g', 't', 't', 'x', 'q', 'o', 'm', 'h', '9481', '1729', '5527', 'u', '3157', 's', '8795', 'z', 'g', 'i', '1649', 'p', '65', 's', 'u', '6843', 'r', 'l', 'k', 'n', 's', 'm', '7991', 'u', 'a']
[A]: a, g, h, i, k, l, m, n, o, p, q, r, s, t, u, x, z


[Q]: ['3611', '6825', 'j', 'e', 'r', 'a', '8889', 'y', 'x', 'k', '2651', '4545', '2289', 'r', 'q', '3163', 'a', 'i', 'j', 't', 'b', '2673', '4307', 'q', '5839', 'w', 'g', '6221', 'g', 'h', 'h', '5815', 'n', '3551', '7709', 'z', '2281', '7987', 'w', 'a', '2319', '3337', '3409']
[A]: a, b, e, g, h, i, j, k, n, q, r, t, w, x, y, z


[Q]: ['p', '4987', 't', 'q', '4333', '7101', '7115', '7565', 'q', '5039', 'o', '9387', 'j', 'n', 'z', '5281', '2149', '1041', '8307', 'b', 'p', 'b', '49', 'm', '3727', '6775', 'z', '3217', '2101', '5401', 'g', 't', '81', '7515']
[A]:
b, g, j, m, n, o, p, q, t, z