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.

['k', 'z', '303', 'a', 'f', 'q', 'i', '1475', '3453', 'd', 'w', '4037', 'z', 'h', 'k', '3547', '1561']
a, d, f, h, i, k, q, w, z

['i', 'x', 'n', 'w', '8915', 'd', 'd', 'd', '6025', '7861']
d, i, n, w, x

['6249', 'p', 'n', '9133', '7123', 'm', '4803', 'c', '6941']

c, m, n, p