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]: ['4637', 'f', '2639', '8623', 'w', 'e', 'k', '5503', 'x', '6633', '7553', '1455', 'u', '1773', 'r', 'u', '1489', 'u', '1303', '9683', 'z', '565', '7041', 'x', 'z', '9431', 'k', 'v', 'j', 'z', '5469', '5665', '4089', '4951', '8263', '5675', '4095', '7745', 'z', '2437', 'd', 'e', 'w']
[EX A]: d, e, f, j, k, r, u, v, w, x, z

[EX Q]: ['h', 'l', 'i', '1507', 'h', '409', '6777', 'u', '5563', '6113', '6513', '9949', '461', 'z', 'm', '2519', 'r', '4699', 'n', 'x', '4645']
[EX A]: h, i, l, m, n, r, u, x, z

[EX Q]: ['1677', '4081', '2311', '5859', '6193', 'c', '2873', '729', 's', '3421', 'e', 'k', 't', '9947', 'p', 'd', 'y', 'q', '4279', 'd', '7325', '8693', '8179']
[EX A]:
c, d, e, k, p, q, s, t, y