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 Q]: ['o', '5503', '5837', '4539', '7631', 'm', '2641', 'p', '7901', '8117', 'z', '3373', '3215', 'v', 'a', '5949', 'w', '9049', 'd', 'a', 'l', 'v', 'l', 'n', 'w', 'r', 'j', '9031', '9609', '4209', 'c', '7453', '5855', '2883', '5941', 't', '4283', 'x', 'x', 'n', 'c']
[EX A]: a, c, d, j, l, m, n, o, p, r, t, v, w, x, z

[EX Q]: ['3043', 'r', 'm', 'i', '2653', 'i', '1703', '1125', '6299', '4863', 'n', 'h']
[EX A]: h, i, m, n, r

[EX Q]: ['x', '5489', 'a', 'm', '2715', 'h', 'n', 'j', '8817', 'o', '939', '9937', '7579', 'p', '809', '5275', 't', 'y', '8881', 'x', 's', 'y', '7157', 'd', 'b', 'l', '3543', 'k', 'f', '1305', '9601']
[EX A]:
a, b, d, f, h, j, k, l, m, n, o, p, s, t, x, y