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]: ['o', '5503', '5837', '4539', '7631', 'm', '2641', 'p', '7901', '8117', 'z', '3373', '3215', 'v', 'a', '5949', 'w', '9049', 'd', 'a', 'l', 'v', 'l', 'n', 'w', 'r', 'j', '9031', '9609', '4209', 'c', '7453', '5855', '2883', '5941', 't', '4283', 'x', 'x', 'n', 'c']
[EX A]: a, c, d, j, l, m, n, o, p, r, t, v, w, x, z

[EX Q]: ['c', '6027', 'o', 'h', 'l', '7893', 'u', 'f', '7661', '4715', '1373', '4799', 'd', 'z', '411', '4753', 'd', '8241', '1589', '4173', '3921', 'j', 'o', '5067', '8879', 'e', 'm', '9543', '9625', '855', 'u', 'd', '5859', '4243', '5747', '5147', '7315', 'd', 'x', 'q', '7841', '7397', 'm']
[EX A]: c, d, e, f, h, j, l, m, o, q, u, x, z

[EX Q]: ['p', '5361', 'k', '5763', 'b', '1077', 'u', 'u', '6859', 'f', 'r', 'm', 'g', 'k', '7789', '7505', 'x', 'd', 'l', '5183', 'u', '7243', '7149', '6735', 'n', 'q', 'c', '5089', '9829', '1449', 's', 'n', '557', 'n', 'v', '8889', '2279', '8119']
[EX A]:
b, c, d, f, g, k, l, m, n, p, q, r, s, u, v, x