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]: ['r', 'y', 'c', '3211', '9245', '8459', '8521', '5781', 'w', 's', 'd', '5299', 'a', 'y', 'g', 'm', '6435', '8605', 'e', 'h', '6871', 's', '387', 'l', '5829', 'e', 'd', '9545', '2945', 'k', 'v', 't', '8449', '2199', 'm', '2599', '1489', '6623', 'x', 'l']
[EX A]: a, c, d, e, g, h, k, l, m, r, s, t, v, w, x, y

[EX Q]: ['a', 'a', 'b']
[EX A]: a, b

[EX Q]: ['n', '1809', '6789', 'm', 'p', 'i', 'u', '2829', 'f', '7145', '3003', 'a', 't', '2625', '8781', 's', 's', '7245', 'e', '7081', '5593', 'c', 'z', '473', 'x', '3201', 'l', '5321', '2007', '4671', 'i', '3193', '4529', 'd', '1277', '2935', 'f', 'a', 'u', 'a', '215', '9091', 'j', '2535', '5343']
[EX A]:
a, c, d, e, f, i, j, l, m, n, p, s, t, u, x, z