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]: ['g', 'h', 'g', 'g', 's', 'h', '2849', '2705', '1185', 'x', '5789', '8221', 'e', 'x', 'g', 'b', '4903', 'q', '1563', 'r', 'k', 't', '9047', 'p', 'p', '9397', 'u', '7473', 'f', 'o', 'y', '1957', '1039', '9905', 'i', '4829', 'q', 'w', 'k', 'p', 't', '563', 'g', 'l']
[A]: b, e, f, g, h, i, k, l, o, p, q, r, s, t, u, w, x, y


[Q]: ['6209', 'x', 'j', 'w', '7965', '4905', '6297', '4291', '7183', 'a', 'l', '5267', 'r', '5935', 'a', '7865', 'h', 'p', '6117', 'a', 'y', 'y', 't', 'v', '7271', 'e', 'e', 'z', 'i', 'l', '4731', '2059', 'm', '5703', 'k', 'f', '8125', 'e', '7569', 'r', '2287', '593']
[A]: a, e, f, h, i, j, k, l, m, p, r, t, v, w, x, y, z


[Q]: ['y', 'n', 't', 'b', '9905', '6727', 'o', '511', '117', 'y', 'h', '3833', '8055', '2601', 's', '5409', 'k', '8279', 'k', '9891', 'g', '5781', 't', '2261', '5187', '8781', 'h', '7113', 'p', '4933', '6971']
[A]:
b, g, h, k, n, o, p, s, t, y