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]: ['9555', '5983', '1853', 'c', 'z', 't', 'p', '9041', 'd', '5919', '1621', '345', 's', '2647', '4261', '8611', 'w', 'x', 'p', '9103', '2599', '5101', '9261', 'k', '7437']
[A]: c, d, k, p, s, t, w, x, z


[Q]: ['p', 'f', 'h', '1977', '6221', 'i', 'a', 'l', '5225', '8059', 'c', 'w']
[A]: a, c, f, h, i, l, p, w


[Q]: ['8601', '5081', '7037', '4197', '6081', '2351', 'u', 'q', 'k', 'd', '3113', '6593', '8699', '7741', 'q', '6649', 'b', '451', '277', '6341', '9883', 'k', 'q', 's', 'l', '65', 'g', '135', 'n', 'h', 'c', 'i', '2791', '6959', 'd', 'f', '675']
[A]:
b, c, d, f, g, h, i, k, l, n, q, s, u