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.

['u', '9249', 'u', 't', 'm', 'm', 'n', 'w', '8617', '2729', 'i', 'l', '2971', '3227', 'b', '9017', '4711', 'i', 't', 'r', 'a', 'a', '1701', '6397', '4535', '9167', '6039', '6111', '849', 'p', '8197', '2645', '5147', 'u', 'l', '7419', 'w', 'w', 'k', 'x', 'c', '3377', '4015', '1297', 'f']
a, b, c, f, i, k, l, m, n, p, r, t, u, w, x

['1931', 'c', 's', '8767', 'z', '8977', '9249', '365', 'p', '7187', 'p', '961', 'k', 'k', '423', '5999', '4697', '6251', '6441', '1821', 's', 's', 'f', '5365', 'z', '5113', 'y', 'k', 'i', '5627', 'u', 'w', '4103', '8035', '7105', 'o', 'n', 's', 'y']
c, f, i, k, n, o, p, s, u, w, y, z

['t', 's', '1971', '7165', 'c', '4593', '3729', '2793', '5665', '5815', '9655', 'u', 'q', 'r', '4023', 'v', 'z', 'r', 'z', '8751', 'e', 'k', '9817', 'f', 'i', 'x', 'j', '4971', 'q', 'h', '2303', '5747', '6289', 'n', 'x', 'r', '7957', '2069', 'w', '9431', 'l']

c, e, f, h, i, j, k, l, n, q, r, s, t, u, v, w, x, z