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: ['6643', '6757', 'h', '1033', 's', 'c', '2003', 'p', '5483', 'f']

Output: c, f, h, p, s


Input: Consider Input: ['o', 'c', '6469', 'x', '8815', '4441', '6193', 'u', 'm', 'a', '9879', 'p', '8335', 'c', 'z']

Output: a, c, m, o, p, u, x, z


Input: Consider Input: ['s', 'j', 'b', '4975', 'v', '77', 'm', '8191', 'b', 'c', 'o']


Output: b, c, j, m, o, s, v