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]: ['2349', 'p', 'a', '435', 'y', 'h', '3249', 'o']
[A]: a, h, o, p, y


[Q]: ['6463', '871', '5781', '283', '9653', 'f', '9661', '3365', '2889', '5499']
[A]: f


[Q]: ['t', 'e', '3117', '6691', '3371', '9665', '863', '9517', 'q', '7091', '5415', 'c', 'x', 'k', '8299', 'n', 's', '9529', 'f', '8511', '1885', 'u', 'z', 'i', '7061', 'x', 't', 'g', 'w', 'c', '6757', 'g', '3171', '279', '8011', '4501', 't', '9249', '61', '6513', 'i', '2149']
[A]:
c, e, f, g, i, k, n, q, s, t, u, w, x, z