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]: ['l', 'u', '3901', '341', '5801']
[EX A]: l, u

[EX Q]: ['5193', 'h', 'm', '703']
[EX A]: h, m

[EX Q]: ['7979', '9561', 'k', '3725', 'n', 'f', '8121', 'd', '6167', '1763', 'p', 'n', 'i', '945', 'f', '331', 'r', 'c', '3089', '6727', '8189', 'r', 'i', '1611', 'w', 'h', '4981', '2857', 'x', 't', '2255', 'l', '1839', '8139', 'i', '5317', 'n']
[EX A]:
c, d, f, h, i, k, l, n, p, r, t, w, x