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]: ['w', '491', 'x', 'u', 'z', 'q', '5411', '7629', '8261', '8629', '1441', '5139', 's', 'm', '6463', 'u', 'z']
[A]: m, q, s, u, w, x, z


[Q]: ['d', '2359', '6571', 'c', 'n', 'u', '9513', '9321', '1689', 'b', '969', '1823', 'e', 'b', '9147', 's', '1811', 'k', '5443', '8699', '5483', 'v', 'w', 'n', '1215']
[A]: b, c, d, e, k, n, s, u, v, w


[Q]: ['6917', 'c', 'h', '9759', 'g', '9955', 's', 'o', 'a', '7851', 'd', '6839', '3395', '3071', 'n', 'l', 's', '7587', 'h', 'a', '4835', 'u', 'u', '1097', '3899', '6289', '9331', 't', 'd', '1641', 'g', '7043', '9711']
[A]:
a, c, d, g, h, l, n, o, s, t, u