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.

['f', '217', '449', 't', 'j', '4097', '5561', '8317', '647', 'u', 'b', '7833', 'r', '9011', 'z', '2753', '2183', 'z', 'o', 'g', '7541', 'b', '8795', '327', 'v', 'e', 't', 'l', '4909', 'k', '7681', 'r']
b, e, f, g, j, k, l, o, r, t, u, v, z

['7677', '4069', 'b', 'w', '4381', 'b', '5757', '711', '765', '8347', '6547', '9527', '945', '5333']
b, w

['1117', '2493', 'm', 'i', 'x', 'd', '655', 'u', '5207', 'a', '4951', '8143', 's', 'f', '8517', 'j', '6123', '1789', '5707', '2459', 'm', '4347', 'k']

a, d, f, i, j, k, m, s, u, x