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: ['w', '743', '5757', '8731', 'k', 'p', '317', 'n', 'x', '5649', 'l', 'm', 'c', '2499', 'l']

A: c, k, l, m, n, p, w, x
****
Q: ['w', '1349', '3393', '7507', '2469', '8531', 'w', '6845', 'k', 'q', '2401', 'f', 'g', 'l', 'n', 'n', 'e', 'q', 'y', 'v', '3077', '4167', 'b', '5517', 'b']

A: b, e, f, g, k, l, n, q, v, w, y
****
Q: ['v', '5697', '6607', 'z', 'v', '2521', '7687', 'q', '1531', '1077', 'y', '1797', '2205', '8115', 'p', '765', '2427', 'k', 'a', 'a', 'v', 'd', 'h', 'b', 'e', 'p', '7863', 'z', 'x', 't', '7673', '9253', 'r']

A:
a, b, d, e, h, k, p, q, r, t, v, x, y, z
****