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 Input:
['8381', 'j', '761', '5431', '7601', 'd', '4339', '1479', 'b', 'x', 'f', 'w', '2437', '7725', '6385', '411', 'w', 'w', 'i', '2769', '5709', '5703', 'k', '5301', '6503', '7833', 'y', '3813', '7061', '5531', 'n', '2251', 'y', '8941', '8481', 's', 't', 't', '3345', 'k', '1545']

Ex Output:
b, d, f, i, j, k, n, s, t, w, x, y


Ex Input:
['4925', 'i', 'q', 'k', '7615', 'r', '7217', 'o', '8097', '9151']

Ex Output:
i, k, o, q, r


Ex Input:
['2775', 'q', 'o', '9555', 'x', '3479', '9171', '7731', 'z', 'h', 'p', '5967', '6915', '3379', '7655', 'x', 'u', '3375', '1645', '3181', 'k', 'h', 'u', 'c', 'm', 'f', '2951', '6285', '117', '591', '4815', 'l', 'i', '4741', 'f', 'u', 'w', 'r', '4523', '8741', '6825', 'd']

Ex Output:

c, d, f, h, i, k, l, m, o, p, q, r, u, w, x, z