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', 'm', '8015', '787', '4787', '1727', 'f', 'e', 'c']
[EX A]: c, e, f, m, o

[EX Q]: ['r', 'q', '3649', 't', '3941', 'z', '3729', 's', 'g', '6905', 'h', 'v', '1085', '6353', 'a', '9395', '5433', 'a', '2565', 'p', 'a', 'h', '1491', 'j', 'b', 'v', 'e']
[EX A]: a, b, e, g, h, j, p, q, r, s, t, v, z

[EX Q]: ['f', 'c', '2161', '7433', 'h', 'h', 'g', '6581', 'z', 'm', 'e', 't', 'n', '9679', 'z', '9631', '6139', '569', '1497', '7915', 'a', 'r', '7993', 'l', '5265', 'k', '9707', '841', '8755', '8351']
[EX A]:
a, c, e, f, g, h, k, l, m, n, r, t, z