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]: ['o', 'm', '8015', '787', '4787', '1727', 'f', 'e', 'c']
[A]: c, e, f, m, o


[Q]: ['5499', 'v', '6507', 'w', 'c', '8431', '8861', '5391', '4765', '4295', '1865', '485', '7255', '1205', 'p', 'w', 'q', '6833', '959', 'a', 'i', '2599', '7779', 'h', '9651', 'g', 'r', 'e', 'u', '4511', '1587', '5601', '8287', '5685', 'u', 'g', '2853', 'p', 'k']
[A]: a, c, e, g, h, i, k, p, q, r, u, v, w


[Q]: ['221', 'q', 't', '9361', 'q', '6847', 'm', 'h', 'w', '8891', 'u', '2719', 'r', '9867', '8593', '741', '847', 'w', 'g']
[A]:
g, h, m, q, r, t, u, w