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', 'q', '6461', 's', '8565', '2237', '2071', '8143', '2977', '5511', 'j', 'o', '5793', 'j', 'm', 'n', '8031', 'j', '535', '5001', 's', 'y', '1737']
[EX A]: j, m, n, o, q, s, y

[EX Q]: ['p', 'v', '1099', 'y', '1313', 's', '181', 'u', 'e', 'u', '8435', '4125', '8661', 'c', '4605', 'f', 'x']
[EX A]: c, e, f, p, s, u, v, x, y

[EX Q]: ['a', '4743', '4331', 'i', '5259', '509', '5543', '6961', '3157', 'n', 'o', '4555', '79', '5519', 'o', 's', 'i', '6071', '4055', '3373', 'e', 's', '2005', '6697', '2593', '623', 'q', 't', 'l', '2571', '2783', '7985', 'p', '2427', 'h', '6995', '2769', 'j', 'r', '7283', 'l']
[EX A]:
a, e, h, i, j, l, n, o, p, q, r, s, t