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: ['7917', '2295', 'q', 'v', '9373', 'w', 'n', 'q', '5803', 'g', 'k', 'm', '2167', 'k', '6425', 'x', 'g', '341', 't', 'u', '8829', 'h', '4333']

A: g, h, k, m, n, q, t, u, v, w, x
****
Q: ['8281', '4831', '1329', 'g', 'e', '8879', 'n', 's', 'x', 'j', '6305', 'j', '921', '3677', '5107', 'n', 'j', '9285', 'a', '5329', '6671', 'c', '9283', 'l', 'a', '7907', 'q', '7605', '855', '6477']

A: a, c, e, g, j, l, n, q, s, x
****
Q: ['c', 'c', 'l', 'l', '179', '6159', '7369', '331', 'f', 'n', 'v', 'u', 'd', '139', 'h', '8981', 'h', 'y', '5809', '1223', '1089', '3939', 'u', '3309', '8627', 'q', 'e', 'l', 'c', '1569', '4319', '4417', '7615', '6449', 'c', 'k', '5363', 'q', '9193', 'd', '8423', '3883', 'c', '65', '9365']

A:
c, d, e, f, h, k, l, n, q, u, v, y
****