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]: ['6143', 'y', '5505', '9813', 'r', 'v', 'u', '8681', '2387', 'u', 'o', 'm', '9793', 'm']
[A]: m, o, r, u, v, y


[Q]: ['1197', '305', 's', '1113', 'n', '2207', 'e', '227', '2833', '607', '3049', 'v', '4615', 'a', 'k', 'r', 's', '3571', 'f', '4215', 'f', '8985', '5559', '4111', 'u', '1433', '1943', '8831', 'w', 'x', 'o', '9023', 'u', 'y', 'p', 's', 'h', '8877', 'p', 'n', '8903', '5811']
[A]: a, e, f, h, k, n, o, p, r, s, u, v, w, x, y


[Q]: ['767', '8685', '5957', '3395', 'u', 't', '1345', 's', 'j', '257', 'k', 'f', 'r', 'u', '1985', 'p', 'i', '7283', 'x', 'i', '1497', '6879', '9911', 'v', 'w', '289', '9623', '3251', 'f', '2925', '2711', 'g', '4285', 'o', 'f', '3961', 't', '281', 'v', '239', '8849', 'k', '7785', 'd', '9625']
[A]:
d, f, g, i, j, k, o, p, r, s, t, u, v, w, x