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', '1349', '3393', '7507', '2469', '8531', 'w', '6845', 'k', 'q', '2401', 'f', 'g', 'l', 'n', 'n', 'e', 'q', 'y', 'v', '3077', '4167', 'b', '5517', 'b']
[A]: b, e, f, g, k, l, n, q, v, w, y


[Q]: ['4371', '9499', 'e', 'w', '9969', '8367', '2897', '1745', 'i', '7049', '9773', 'h', '9649', 'u', '4673', '8513', '8547', 'z', '1995', '7739', '2215', '171', 'c', '7527', '2479', 't', '5223', 'p', '2313', '3243', '2281', 'r', 'c']
[A]: c, e, h, i, p, r, t, u, w, z


[Q]: ['9417', '5689', '2067', 'x', '1877', 's', 'n', 'm', '9941', 'k', 'k', 'z', 'o', 'f', '979', '6371', '849', '2365', 'y', '7095', '769', 'l', 'v', '1993']
[A]:
f, k, l, m, n, o, s, v, x, y, z