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.

Input: Consider Input: ['d', '4377', '9271', '8053', '9519']

Output: d


Input: Consider Input: ['o', 'z', 'h', '3965', 'n', '3009', '173', '997', '3987', '5799', '2331', 'p', 'x', '897', '8213', '451', 'u', 't', 't', '9917', '4501', 't', 'c', 'i', 'w', 'w', 'u', '2977', 't', 'b', '4161', '9281', 'w', 'f', '3137', '5745', 'e', '673', '6363', 'h', 'q', 'x', 'm', '9505']

Output: b, c, e, f, h, i, m, n, o, p, q, t, u, w, x, z


Input: Consider Input: ['t', '3357', '6843', '9491', '9445', '7285', 'u', 't', '4557', 'a', '4445', '433', 'r', '8381', '8155', '31', 'h', '1411', 'u', 'm', 'j', 'n', 'y', 'm', 'v']


Output: a, h, j, m, n, r, t, u, v, y