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]: ['7965', '6465', 'c', '7963', 'j', '6839', '9989', '1019', 'x', '1303', '2633', 'y', '6865', 'a', 'k', '635', '3719', '7229', 'k', 't', 'r', '5741', '9569', '4931', '1125', 'f', '5429', 'c', '2065', '6315', 'e', '6877', '2005', 'x', '7831', '7297', 'm', '3571', 'b', '8617', '2981', 'i', '5105', 'g', 'u']
[A]: a, b, c, e, f, g, i, j, k, m, r, t, u, x, y


[Q]: ['c', 'e', '6509', '1295', 'u', '5445', '1731', '3049']
[A]: c, e, u


[Q]: ['e', 'x', 'z', '5705', '4669', '8559', '6771', 'g', 'n', '5027', '8775', 'x', '1421', '4009', 'g', 'm', 'c', 'i', 'b', 't', '513', '3879', '5141', '2865', 'i', '2559', '2135', 'p', '2153', 'd', '393', '2821', '3009', '821', '353', '2041', '9081', '3665', '4757', '2247', 'b']
[A]:
b, c, d, e, g, i, m, n, p, t, x, z