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:
['6175', '9441', '7127', '5979', 's', '1367', 'e', 'm', '7083', '1787', '8375', '2851', '3475', 'r', '697', 'g', 'z', 'm', '4207', 'c', '7971', 'z', '9339', 'd', 's', '3507', '9003', 'i', 'y', 'w', 'j', 'i']

Ex Output:
c, d, e, g, i, j, m, r, s, w, y, z


Ex Input:
['3627', '2051', '3203', 'c', 'r', 'a', '1453', 'e', 'z', 't', '1093', '4651', 'a', 'f', '8159', '9623', 'l', 't', 'r', '6963', '7071', '8103', '3493', 'y', '2369', '609', '2011', 'f', '187', 'f', 'c']

Ex Output:
a, c, e, f, l, r, t, y, z


Ex Input:
['5073', 'w', '5175', 'z', 'b', '9629', '5555', 'u', '695', 'i', 'm', 'j', '3351', 'w', '1387', '9131', 'd', 'b', 'y', '3501']

Ex Output:

b, d, i, j, m, u, w, y, z