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.

['s', 'c', 'e', '2457', '9413', 'r', '9949', 's', 'z', 'e', 'a', 'o', '7207']
a, c, e, o, r, s, z

['p', '5229', '7521', 'y', 'n', 'u', 'c', '4047', '781', 'a', '4707', '7149', 'j', 'm', 't', '515', '7691', 'h', '4879', 'j', '6593', 'n', 'p', '2949', '1343', 'y', '2629', 'p', 'b', 'b', '2861', 'a']
a, b, c, h, j, m, n, p, t, u, y

['8713', 'n', '1085', 'v', 'h', 's', '4385', '2871', 'd', 'f', 'n', '4053', 'w', 'n', '675', 't', '6421', 'z', 'n', '4141', 'k', 'g', 'v', '3617', '6263', '6475', 'j', 'e', '333', '535', '6239', 'o', '7799', 'i', '7913']

d, e, f, g, h, i, j, k, n, o, s, t, v, w, z