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.

['6643', '6757', 'h', '1033', 's', 'c', '2003', 'p', '5483', 'f']
c, f, h, p, s

['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']
a, c, d, j, l, m, n, o, p, r, t, v, w, x, z

['v', '513', '2429', 't', 'o', 'h', '2317', '2307', 't', '4905', 'j', 'p', '7819', 'm', '7283', 'z', 'q', 'm', '9075', '1515', 'v', '5245', '3253', 'a', 'l', '8319', 'e', '4141', '5995', '2681', '9965', '1855', '6541', 'd', 'y', '7639', '2777', 'd', 'k', 'n', 'm', '2673']

a, d, e, h, j, k, l, m, n, o, p, q, t, v, y, z