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.

Ex Input:
['7965', '6465', 'c', '7963', 'j', '6839', '9989', '1019', 'x', '1303', '2633', 'y', '6865', 'a', 'k', '635', '3719', '7229', 'k', 't', 'r', '5741', '9569', '4931', '1125', 'f', '5429', 'c', '2065', '6315', 'e', '6877', '2005', 'x', '7831', '7297', 'm', '3571', 'b', '8617', '2981', 'i', '5105', 'g', 'u']

Ex Output:
a, b, c, e, f, g, i, j, k, m, r, t, u, x, y


Ex Input:
['4993', 'n', '7115', 'f', 'd', 'q', '249', '3203', 'w', '5689', '4103', '7129', '603', 'e', 'z', '5571', '3241', '6029', '2721', '8451', 'o', '7841', 'p', '6271', 'r', 'b', '9481', '4045', 'v']

Ex Output:
b, d, e, f, n, o, p, q, r, v, w, z


Ex Input:
['v', '3439', 'h', '6867', '3185', 's', '9925', 'm', '781', 'o', '6235', 'r', 'k', 'u', 'w', 'o', '9469', 'y', 'd', '4595', 'h', 'u', 'w', '7497', '2589', '3775', 'm', '4837', 'o', 'l', '3733', 'y', '8785', '5327', 'd', '9411', '3179', 'm', '5917', '1829', 'r', '7879', 'u', 'k', '6719']

Ex Output:

d, h, k, l, m, o, r, s, u, v, w, y