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.

[Q]: ['m', '6443', 'd', 'o', 'p', 'q', '3765', 'k', 'm', 'y', 'j', '3531', 'y', 't', '671', 'j', '3699', 'a', 'i', '1843', 't', 'd', '1205', 'k', 'h', '1209', '2913', '1301', 'k', 'd', '1769', '7985', 's', 'p', 'f', '4583']
[A]: a, d, f, h, i, j, k, m, o, p, q, s, t, y


[Q]: ['699', 'd', '6027', 'j', 'e', 'c', 't', '9983', '5471', '2649', 't', '2631', 'r', 'h', '293', 'j', '8699', 'p', 'k', '5433']
[A]: c, d, e, h, j, k, p, r, t


[Q]: ['c', '6503', '5021', '1461', 'g', '3061', '1159', '5573', '5247', '297', 't', 'u', '5717', 'z', 'w', '1949', 'b', '4327', '285', '6149', '649', 'k']
[A]:
b, c, g, k, t, u, w, z