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]: ['d', 'r', '7769', '2159', 's', '3269', '5527', 'l', 'z', 'e', '5165', 'x', 'x', '8273', 'g', 'm', '7609', '4015', '6403', '3753', 'y', 'h', 'l', 'i', '389', 'm', 'u', '6845', 'r', 'c', '7571', '3355', '9755', 'n', '4625', 'p', '5645', '1703', '4439', 't', '8431']
[A]: c, d, e, g, h, i, l, m, n, p, r, s, t, u, x, y, z


[Q]: ['r', '9489', 'e', 'n', '6323', 'd', '3163', '265', '8587', '7891']
[A]: d, e, n, r


[Q]: ['8247', 't', '6957', '9189', '1137', 'n', '7439']
[A]:
n, t