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.

['5973', 'h', '4081', 'i', '8059', 'w', 'j', '6175', 'w', '8685', '5811', 'k', 'n', '5577', '9817', 'v', '8617', 'u', 'y', '3921', 'b', '1027', '5405', 'a', '3501', '6659', 's', 'e', '157']
a, b, e, h, i, j, k, n, s, u, v, w, y

['331', '125', 'u', 'a', 's', '6995', 'i', '3613', '9727', '7087', 'l', 'b', '8291', '813', 'i', '1169', '2159', 'd', '1451', 'q']
a, b, d, i, l, q, s, u

['4395', '3933', '4535', 'e', '1127', '2775', '9625', '4815', '1505', '3667', 'k', '6523', 'k', 'g', '8597', 'm', 'f', '4973', 'k', 'f', 'x', '919', 'e', 'h', 'x', 'i']

e, f, g, h, i, k, m, x