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.

[Q]: ['h', '1797', '8211', 'n', 'r', '7707', '2063', '4655', 'x', '5521', '8327', 'g', '7659', 'i', 'x', 'w', '9465', '4625', 'q', '5377', 'r', '225', 'r', 'i', 'e', '4163', 'g', 'g', '3537', 's']
[A]: e, g, h, i, n, q, r, s, w, x


[Q]: ['9923', 'x', '1901', 'v', '1459', '7503', '3829', '4929', 'k', 'c', '3329', '8793', 'n', 'a', '7249', 'b', 'l', 'l', 'm', 'p', 'b', 'a']
[A]: a, b, c, k, l, m, n, p, v, x


[Q]: ['7577', '4543', '8319', '5477', 'm', '7859', 'h', 'h', 'v', '8317', '7807', '7935', 'p', 'p', 'k', '5423', '6979', 't', '9395', 'm', 'r', 'z', 'b', '7581', '7243', 'g']
[A]:
b, g, h, k, m, p, r, t, v, z