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]: ['459', '1729', 'b', 'c', '9619', '4461', '4347', '6733', 'i', '3631', 's', 'j', 'i', 'r', '5293', 'q', '7397', '4309', 'c', 'n', 'k', '197', 'q', '8139']
[EX A]: b, c, i, j, k, n, q, r, s

[EX Q]: ['491', '229', 'g', '6677', '4793', 'h', 'x', 'a', '2333', 'u', 'l', '785', 'p', '7331', '653', '5193', '5415', '8417', 'v']
[EX A]: a, g, h, l, p, u, v, x

[EX Q]: ['3751', '9635', 'h', '7953', 'n', '2795', 'i', '77', '5539', 'r', 'v', '4087', 'd', 'i', 's', '2125', 'i']
[EX A]:
d, h, i, n, r, s, v