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.

['8235', 't', '1695', '9899', '3633', 't', '1823', 'r', 'x']
r, t, x

['2103', '7937', 'v', '7641', '6609', '269', '4463', '4333', 'c', '8407', '4883', '6283', 'a', '8643', '3365', '1929', 'v', 'o', '2107', '7453', '9157', '5581', '5187', 'f', 'k', '8227', '6295', 'b', 'y', '4995', '1187', 'k', 'n', 'p', 'z', '8165', 'n', '7345', 'l']
a, b, c, f, k, l, n, o, p, v, y, z

['d', 'i', '2887', '7433', '7557', 'k', 'c', '7865', '5295', 'v', '6167', '8945', 'z', 'j', 'y', '6931', 'i', 'z']

c, d, i, j, k, v, y, z