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]: ['5431', 'o', 'u', 'l', 'f', 'd', 'r', '1479', '9357', 's', 'v', '6399', 'b', '7937', 't', '8497', 'r', '131', 'h', 'c', 'v', '8879', 'k', 'r', '4687', 'l', '1065', 'r', 'w', 'l', '3305', '461', 'q', 'h', 'b', 'e', 'e', 'w', '5999']
[A]: b, c, d, e, f, h, k, l, o, q, r, s, t, u, v, w


[Q]: ['5337', '4877', '9443', '3445', 'u', '2571', 't', 'n', 'x', '1985', '5145', '3397', 'p', '9259', 's', 'x', 'u', 'c', 'g', 't', 'j', '829', '8273', 'e', 'j', 'r', 'x', '865', '4773', 'h', '4407', '8591']
[A]: c, e, g, h, j, n, p, r, s, t, u, x


[Q]: ['r', 'y', '9919', 'l', '2495', 'v', 'x', 'm', 'f', '5137', '8615', '9733', 'c', '265', 'r', '9735', '5315', '9615', '6781', 't', 'l', '6901', '8531', 'z', '5007', '5763', 'z', '3123', '57', '993', 't', 'l', 'g', 'h', 'n', 'w']
[A]:
c, f, g, h, l, m, n, r, t, v, w, x, y, z