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]: ['1801', 'q', '5101', '8863', '2309', 'p', '8789', '9529', '6135', '5523', 'f', '8889', '7639', 'k', '263', '5751', '5529', 'g', '1451', '4143', 'e', '6987']
[A]: e, f, g, k, p, q


[Q]: ['8489', 'h']
[A]: h


[Q]: ['799', 's', '3273', 't', '8451', 'b', '1325', '787', '6693', '1617', 'x', '6383', '8381', 'k', '281', '7151', 'x', 'q', 'p', '5285', '7849', '6655', 'g', '6197', '5245', '3635', 'k', 's', 'p', '9771', '965', '8761', '6833', 'g', 'y', '1885', 'p', '935', '7637', 'x', 'n', 'y', 'n']
[A]:
b, g, k, n, p, q, s, t, x, y