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]: ['c', 'e', '6509', '1295', 'u', '5445', '1731', '3049']
[A]: c, e, u


[Q]: ['c', '9125', '6049', '5201', 'v', '9311', 'q', '3305', 'l', 'q', '3387', '3647', 'x', '471', 'a', '5631', 't', '9679', '5423', '2569', 'w', 't', '6397', 'e', 'h', 'c', 'v', 'v']
[A]: a, c, e, h, l, q, t, v, w, x


[Q]: ['m', '2223', 'd', '5317', 'l', '8447', 'v', '713', 'v', '315', 'h', 'x', 'w', '371', '5419', '1143', '8881', 'a', '3349', 'b', 't', 'l', '8513', '7541', '5533', 'j', '613', '7991', 'x', 'n', 'a', '9949', 'm', 'y', '6209', 'g', '8843', 'k', 'd', '3141', '7203', '8081', '4009']
[A]:
a, b, d, g, h, j, k, l, m, n, t, v, w, x, y