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]: ['5499', 'v', '6507', 'w', 'c', '8431', '8861', '5391', '4765', '4295', '1865', '485', '7255', '1205', 'p', 'w', 'q', '6833', '959', 'a', 'i', '2599', '7779', 'h', '9651', 'g', 'r', 'e', 'u', '4511', '1587', '5601', '8287', '5685', 'u', 'g', '2853', 'p', 'k']
[A]: a, c, e, g, h, i, k, p, q, r, u, v, w


[Q]: ['6709', 't', 'n', 'k', '991', 'a', '8899', '3563', '527', 'm', '4599', '6679', 'm', 'x', 'f', 'o', '3275', 'x', '677', 'b', '3329', '3593', '5183', '5753', 'u', '6045', '2607', 'y', '9873']
[A]: a, b, f, k, m, n, o, t, u, x, y


[Q]: ['o', '3903', '1095', '7763', 'o', '5183', '1683', '8669', '7549', 'm', 'k', '5659', '4981', '7445', '6129', '4749', '997', 'b', 'e', '4949', 'm', 'y', 'g', '3425', '8417', 'o', 'k', '1291', 'b', 'p', '2513', '7745', 'w', '5525', 'e', 'n', 'q', '7965', '3243', '7893', '3833', '7059', 'c', 'h']
[A]:
b, c, e, g, h, k, m, n, o, p, q, w, y