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:
['6627', '8037', 'q', 'e', 'j', 'p', '9613', '9317', 'm', 'm', '5345', 'f', '8105', '5665', '4175', '4793', '3707', 'i', 'b', '6745', '747', '8329', '1481', 'b', '8949', 'n', '4803', '1359', '3533', 'f', '543', '3003', '6943']

Ex Output:
b, e, f, i, j, m, n, p, q


Ex Input:
['y', 'u', 'c', '5909', 'x', '9865', 'e', 'h', '5125', '4719', 'w', '8855', 'i', 'd']

Ex Output:
c, d, e, h, i, u, w, x, y


Ex Input:
['n', 't', '5989', '27', 'o', '5403', '9961', '3305', '3885', 'j', '9693', 'a', 'j', 'm']

Ex Output:

a, j, m, n, o, t