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.

['v', '6635', '5395', '3263', '4391', 'h', '1521', 'f', '9861', '6125', '1673', '3679', '8681', '4967', 'f', 'a', 'c', 'k', 'n', '4155', 'e', 'm', 'i', '1699', 'r', 'f', 'u', 'r', '3451', 'v', '7239', 'o', '4359', 'l', 'a', '2925']
a, c, e, f, h, i, k, l, m, n, o, r, u, v

['1627', 'r', '2429', 'b', '4451', 's', 'k', 'm', '269', 'l', '709', 's', 'q', '985', 'x', 'j', 'k', 'k', '6603', 'v', '9497', '477', '5803', 'c', 't', 'f', '3189', '6419', '8561', '5709', 'u', 'z', '5717', '9711', 'w', 'y', 'm', 'v']
b, c, f, j, k, l, m, q, r, s, t, u, v, w, x, y, z

['7599', '1593', 'y', '5323', 'i', '2811', '3271', 'p', '9913', 'd', 's', 'h', '3147', 'x', 'b', '3635', '379', 'j', '5531', '3789', '1273', 'c', '9725', '5361', '8409', 'm', '989', '7933', '8077', '1565', '705', 'n', 'w', 'w', 'f', 'g', '6503', '1895', 'q', 'w', 'b', 'i', '4173', 'i', '2847']

b, c, d, f, g, h, i, j, m, n, p, q, s, w, x, y