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: ['4423', '8295', 'h', '4881', 'j', 'c', '1185', 'z', 'm', '2725', 'p', '9187', '6275', '1617', '2523', '9879', '4149', '2197', '3909', '5155', '691', 'r', 'e', 'u', 'l', 'd', '1581', '2763', 'c']

A: c, d, e, h, j, l, m, p, r, u, z
****
Q: ['b', 'a', 'a', '623', '3031', '8973', '1205', 'o', '5295', '6577', '4107', '7627', '3061', '179']

A:
a, b, o
****