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]: ['k', 'j', 'v', '5277', '8607', 'n', '1109', 'e', 'k', '6579', 'o', '2909', 'u', 't', '9685', '8443', '9257', '8071', 'y', 'b', 'h', '4767', 'a', 'j', '8455', 'b', '7733', '2553', 'e']
[A]: a, b, e, h, j, k, n, o, t, u, v, y


[Q]: ['c', '7039', 'g', '1899', 'r', '507', 'c', '2587', '3865', '1729', '3927', 'r', '3535', '2791', 'm', 'l', 'r']
[A]: c, g, l, m, r


[Q]: ['b', '4901', '2217', '1003', '5451', 'x', 'k', '1865', '3077', 's', '7973', 'p', 'u', 'b', '7457', '8219', 'n', 'p', 'w', 'h', '3179', 'w', 'u', 'c', 'h', '287', 'p', 'q', 'c']
[A]:
b, c, h, k, n, p, q, s, u, w, x