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]: ['g', 'x', 'l', 'e', 'd', '1345', '1763', 'm', 'c', '2057', 's', 'a', '4127', 'y', 'h', '8581', 'o', '9203', '4761', 'd', 'u', 'n']
[EX A]: a, c, d, e, g, h, l, m, n, o, s, u, x, y

[EX Q]: ['7561', 'r', '3419', 'k', 's', '5997', 'u', '6635', '7003', '8491', 'i', '9835', 'c', '8827', 'h', 'a', 'j', '7675', '1995', '1223']
[EX A]: a, c, h, i, j, k, r, s, u

[EX Q]: ['6953', 'u', 'j', '6125', '9587', '1095', 'o', 't', '9143', '8531', 'g', '769', '1879', 'x', 'j', '9045', 'o', 'p', 's', '1075', 't', '6843', '3287', 'g', '489', 'c', '1455', '9065', '2275', 'o', 'v', '6755', '2393', '8083', 'k', '2355', 'i', 't', '145', 'c', '9287', '4333']
[EX A]:
c, g, i, j, k, o, p, s, t, u, v, x