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]: ['i', '9215', 'n', 'p', '4815', '8757', 'm', '1755', 'c', 'z']
[A]: c, i, m, n, p, z


[Q]: ['2915', '6033', '5541', '4685', '1263', '6701', 's', '7269', 'g', '8033', '8171', '6917', 'l', '2913', '447', 'g', 'a', 'z', 'o', '7563', '5385', '5259', '5067', '4869', '2653', '6925', '7001', '8553', 'x', '1243', '9131', '5037']
[A]: a, g, l, o, s, x, z


[Q]: ['r', '3223', 'z', 'j', '6233', 'x', 'm', 'b', 'i', '219', '8591', '2419', 'x', 'n', '375', '4411', '1345', 'm', '7869', 'j', '2233', 's', 'l', '4625', 'r', 'n', 'y', '6159', 'q', '4529', '313', '4523', 'i', 'a', 'r', 'r', 'd', '183', 't']
[A]:
a, b, d, i, j, l, m, n, q, r, s, t, x, y, z