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]: ['u', '1805', 'l', 'l', '5449', 'r', '4471', 'a', 'u', 'c', 'q', '6463', '6717', '7025', '9359', 'q', 'h', '1989', '5497', 'h', 'd', 'c', '135', '5737', '1235', 'v', 'u', 'g', 'p', 't', '9223', '8289', '4489', 'n']
[A]: a, c, d, g, h, l, n, p, q, r, t, u, v


[Q]: ['z', '8763', '6399', '45', '6731', 'v', '441', '4763', 'u', '8741', 'r', '9143', 'd', 'p', '2241', 'y', '6523', 'y', 'w', '6771', 't', 'r', '9239', '295', 'z', '461', 'b', '9217', '2597', '1249', 'r', 'i']
[A]: b, d, i, p, r, t, u, v, w, y, z


[Q]: ['9891', '3343', '5201', '7439', '9685', '499', '2083', '5815', 'a', 'c', '5571', '3525', 'c', 'a', '5549', 't']
[A]:
a, c, t