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: ['2705', 'n', 'r', '8259', '6839', '3239', 'w', 'z', '2611', '2957', '2303', '6315', '7801', 'c', 'w', 'm', '5049', '6465', '599', 'h', 'q', '7559', 'n', '9917', 'v', 'l', '643', '6415', '3587', 'c', '917', '4435', 'p', 'a', '317']

A: a, c, h, l, m, n, p, q, r, v, w, z
****
Q: ['9025', '3259', '4863', 'u', '6443', '9931', '627', 'x']

A: u, x
****
Q: ['j', '9921', '4465', 'x', '4501', 'a', '1789', '5629', 'h', '8605', 'a', 'm', 'v', 'i', 'k', '9399', '4975', 'd', 'u', '2565', '5941']

A:
a, d, h, i, j, k, m, u, v, x
****