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]: ['u', '635', '5249', '9457', 's', '9317', '9407', 'l', 'w', '9705', 'k', '429', '5489', 'e', 'd', '2457', 'o', '4665', '1675', 'l', 'y', 's', 'o', 't', '4285']
[EX A]: d, e, k, l, o, s, t, u, w, y

[EX Q]: ['o', 'h', 'z', 'n', 'e', 'y', 't', '4371', 'm', '1059', '4853', '8529', 'l']
[EX A]: e, h, l, m, n, o, t, y, z

[EX Q]: ['5733', '6039', 'u', '7433', '3285', '9277', '1051', 'l', 'a', 'n', '7069', '9123', '6913', '589', 'j', 'n', '5741', 'j', '1045', '3545', 'c', 'r', 'k', 'n', '7171', 'h', '511', '3407', 'r', 'y', '2033', 'g', '5059', 'i', 'l', 'm', 'u', 'n']
[EX A]:
a, c, g, h, i, j, k, l, m, n, r, u, y