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]: ['u', 'i', '1185', '3795', '5417', 'k', 'b', '2629', '2635', 'z']
[A]: b, i, k, u, z


[Q]: ['e', '8391', '7065', '6141', '3335', 't', 'i', 'c', '1791', '6333', 'b', 'z', '1621', 'e', 'h', 'u', 'o', 'q', '3195', '6507', '3253', 'c', '2067', '3917', '7111', 'r', 'j', 'd', '3987', '9139', 'm', '981', 'l', 'f', '2417', 'w', '9983', 'h', 'd', '6021', 'a', 'f']
[A]: a, b, c, d, e, f, h, i, j, l, m, o, q, r, t, u, w, z


[Q]: ['x', 'p', '7541', 'f', '689', 'r', '703', '9275', 'b', 't', '7395', '6249', 'v', '4539', '9671', '3145', '789', 'd', 'k', 'y', '7825', '1345', '4317', 'j', 'n', 'y', '8113', 'j', 'p', '6765', 'i', '2513', '9697', '9147']
[A]:
b, d, f, i, j, k, n, p, r, t, v, x, y