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]: ['n', 'y', '7087', '9539', 'x', 'i', 'w', '7237', '8613', 'k', '5999', '4179', 'o', 'm', '7485', '1955', 'w', '1451', 'h']
[EX A]: h, i, k, m, n, o, w, x, y

[EX Q]: ['395', '8309', 'v', 'r', 'x', 'j', 'l', 'b', 'c', 'c', '3123', 't', 'a']
[EX A]: a, b, c, j, l, r, t, v, x

[EX Q]: ['489', 'd', '7747', '5807', 'q', 'k', 's', 'n', 'e', '1965', '5603', 'j', 'd', '9649', 'q', 'f', 'r', 'f', 'i', '5705', '1047', 'u', '7935']
[EX A]:
d, e, f, i, j, k, n, q, r, s, u