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]: ['5181', '8651', '963', '2111', 'g', '7913', '8335', 'o', '1387', '9225', '6517', 's', 'r', '2291', '3699', 'y', 'y', '4223', 'i', '9109', 'm', 's', '8585', 'l']
[A]: g, i, l, m, o, r, s, y


[Q]: ['9947', '3353', '8643', '4621', '4857', 'y', '7075', 'c', '8911']
[A]: c, y


[Q]: ['3071', 'f', '2661', '9937', 'd', '8873', '5373', 'f', '5219', '2647', 'q', 'd', 'm', 'c', 'd', '3259', '6343', '5647']
[A]:
c, d, f, m, q