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 Input:
['f', '3409', 'i', '4147', '1745', '6007', 'l', 'd', 'i']

Ex Output:
d, f, i, l


Ex Input:
['f', 'a', 'r', '4009', 'k', 'a', 'g', '7725', 'v', 'b', '6705', 'a', '6583', '3159', 'c', 'w', 'x', 'h', '7625', 'p', 'y', '5645', 'k', 'r', 'j', '4175', 'r', '3103', '8631', '5999', 'p', 'g', 'h']

Ex Output:
a, b, c, f, g, h, j, k, p, r, v, w, x, y


Ex Input:
['3837', '3061']

Ex Output:

-1


