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.

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

[EX Q]: ['r', 'q', '3649', 't', '3941', 'z', '3729', 's', 'g', '6905', 'h', 'v', '1085', '6353', 'a', '9395', '5433', 'a', '2565', 'p', 'a', 'h', '1491', 'j', 'b', 'v', 'e']
[EX A]: a, b, e, g, h, j, p, q, r, s, t, v, z

[EX Q]: ['6833', '581', '6585', 'g', 'l', '4937', 'd', 'i', '5597', 'd', '9303', '6345', '2201', 'o', 'c', 'z', '9783', 'r', 's', 't', 'u', 'l', '2997', 'c', '1401', '3137', 'l', '2271', 'n', 'k', 'c', '1321', 'l', '4439', 'r']
[EX A]:
c, d, g, i, k, l, n, o, r, s, t, u, z