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]: ['s', '6723', 'l', '1573', '1129', 'n', '4277', '5003', 'y', '7563', 'c', '6747', '3105', 's', '3593', '8417', '8253', '4157', 'w', 'f', 'z', 'd', '9685', '1033', 'h', '4893', 't', 'j', '6821', 'z', 'a', 'u', '591', 'o', '1087', '2147', '1223', '2339', 'i', 'y', '9307', 'x', 'z', 'r', 'y']
[EX A]: a, c, d, f, h, i, j, l, n, o, r, s, t, u, w, x, y, z

[EX Q]: ['4743', '9687', '2887', '4413', 'r', 'w', '2355', 'l', 'd', '453', 'o', 'm', '4351', '5881', '3963', 'g', 'r', 'z', 'q', '7555', 'y', '9555', '405', 'n', 'l', '6733', '1763', 'v', '9925', 'y', '633', '827', 'w']
[EX A]: d, g, l, m, n, o, q, r, v, w, y, z

[EX Q]: ['a', 'n', 'b', '9093', 't', 'n', 'u', 'q', 'p', 'k', 't', 'b', 'i', 'c', '2747', 'w', 'z', '1357', 'n', '335', 'a', 'g', 'j', '8181', 'o', '5373', 's', '9283', '2187', 'h', '335', '347', 'b', 'z', '9133', 'h']
[EX A]:
a, b, c, g, h, i, j, k, n, o, p, q, s, t, u, w, z