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]: ['n', '6615', 'r', 'q', '3803', '4641', '9775', '7719', 'n', '6571', '2723', '6919', 'e', 'f', '1919', '6963', '2581', 'y', '713', 'w', 'w', 'w', 'l', 's', '3993', '9563', '9365', '9277', '103', '2737', 'y', '6005', '9763', 'p', '261']
[EX A]: e, f, l, n, p, q, r, s, w, y

[EX Q]: ['k', 'r', 'f', '4369', 'z', 'z', 'l', '143', 'r', '707', '9167', 'g', '1749', 'i']
[EX A]: f, g, i, k, l, r, z

[EX Q]: ['3735', '2889', 'p', '8277', '4487', 'r', '3371', '1411', 'l', 'x', 'r', 'o', '4061', '4055', '4683', 'm', 't', '873', 'x', '4359', '801', 'v', 'k', '7151', '2949', 'm', 'j', '3717']
[EX A]:
j, k, l, m, o, p, r, t, v, x