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]: ['h', '6865', '4019', '8571', 'y', '5575', '7835', '9537', 'n', '875', 't', 'a', 's', '2769', 'p', '1607', 'n', '4087', '961', '7869', '5085', '2131', '4867', 'j', 'h', 'y', '3105', '6609', 's', 'l', '3399', '5013']
[A]: a, h, j, l, n, p, s, t, y


[Q]: ['887', 'p', '3819', '2727', '1407', 'b', 'n', '737', 'd', 'w', 'q', '6877']
[A]: b, d, n, p, q, w


[Q]: ['t', '1435', 'l', 'x']
[A]:
l, t, x