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]: ['d', 'p', 'k', '9679', 'x', 'j', '7481', '1815', 't', 'w', '6513', 'j', '5079', '5219', 'p', '9545', 'a', '1931', '9973', '8125', '5169', '2791', 't', 'd', '2057', 'e', 'x', 'y', '7409', 'u']
[A]: a, d, e, j, k, p, t, u, w, x, y


[Q]: ['7911', '7175', 'y', '9173', 'y', '2529', '831', 'k', '7197', 'j', '2343', 'i', 'b', '6799', '5987', '7277', 'n', 'x', 'h', '7209', 'l', 'd', 'm', 'e', '2277', '8909', 'x', '5361']
[A]: b, d, e, h, i, j, k, l, m, n, x, y


[Q]: ['t', '7025', 'v', '7209', '2951', '4617', 'u', 's', '6619', '1199', '8161', '2251', 'e', '9345', '9005', '6255', 'c', 'y', '7993', 't', '2825', 'l', '8765', '7265', 'e', '6051', '865', 'h', '6153', 'r', 'o', '1337', '6943', '793', 'g', '7241', 's', 'k', 'x', 'q', '5639', 'k', 't']
[A]:
c, e, g, h, k, l, o, q, r, s, t, u, v, x, y