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.

['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']
b, d, f, i, j, k, n, s, t, w, x, y

['587', '3903', 'z', 'l', 'k', '5693', 'x', '1695', 'c', '3185', 'g', '9491', '8185', '1285', '2533', '6825', '3187', '6039', 'e', '251', 'w', '7741', '9573']
c, e, g, k, l, w, x, z

['c', 'v', '5835', '6241', 'i', 'u', 'c', '5517', '4223', 'h', 'q', '3799', '1663', '4431', '6081', '4307', '6325', '9935', '617', '155', '5015', 'g', '9431', 'y', 'k', 'i', 'k', '9957']

c, g, h, i, k, q, u, v, y