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.

[EX Q]: ['u', '9249', 'u', 't', 'm', 'm', 'n', 'w', '8617', '2729', 'i', 'l', '2971', '3227', 'b', '9017', '4711', 'i', 't', 'r', 'a', 'a', '1701', '6397', '4535', '9167', '6039', '6111', '849', 'p', '8197', '2645', '5147', 'u', 'l', '7419', 'w', 'w', 'k', 'x', 'c', '3377', '4015', '1297', 'f']
[EX A]: a, b, c, f, i, k, l, m, n, p, r, t, u, w, x

[EX Q]: ['t', 'm', '7071', 'j', '353', 'n', 'a', 'm', '9211', 'i', '9537', 'q', '7669', '869', '8753', '8071', '375', '9971', 'c', 'n', '5851', 'u', '2491', '2697', '2789', '4683', '879', 'q', 'g', 'p', 'd', 'x', 'r', 'i', '8171', '5449', '2477', '1151', 'z', '3845', '1079', 'j', 'n', 'p', '8199']
[EX A]: a, c, d, g, i, j, m, n, p, q, r, t, u, x, z

[EX Q]: ['s', '4705', '3111', '2585', 'b', 'm', '1401', 'm', '5541', '7835', '987', 'r', '6201']
[EX A]:
b, m, r, s