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.

['2775', '7507', 'c', '4417', '3449', 'y', 'z', 'e', 'f', '9515', '8555', '7269', '8353', '4239', '4347', '4479', '8645', '9925', 'o', 'h', 'o', '8641', 'y', '3251', '1191', 't', 'x', 'z', '7203', 'b', 'b', '7545', '7283', 'z', 'y', '8127', 'x', 'l', '6251', 'y']
b, c, e, f, h, l, o, t, x, y, z

['d', 'g', '9019', '9987', '8713', '9513', 'a', '2043', 'd', '5817', 'w', 'd']
a, d, g, w

['c', '6267', '1981', '9607', 'm', '5307', '1653', 'k', '1873', 'a', 'n', '4691', '3745', '257', 'i', '1749', 'u', 'h', '785', '2077', '2229', '3673', '5163', 'o', 't', 'j', 'd', 'y', 'o', '9135', 'e', 'i', 'o', 'w', 'd', '2997', '8043', 'g', '8421', '611', 'c', 'l', 'b', '6503', '3125']

a, b, c, d, e, g, h, i, j, k, l, m, n, o, t, u, w, y