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.

['4993', 'n', '7115', 'f', 'd', 'q', '249', '3203', 'w', '5689', '4103', '7129', '603', 'e', 'z', '5571', '3241', '6029', '2721', '8451', 'o', '7841', 'p', '6271', 'r', 'b', '9481', '4045', 'v']
b, d, e, f, n, o, p, q, r, v, w, z

['x', 'b', '1467', 'y', '2101', 'y', 'm', '2745', 'z', '429', '7523', 'e', 'f']
b, e, f, m, x, y, z

['x', 'n', 'c', '7199', 'g', '231', 'r', 't', 'o', '7515', '9511', '5175', 'q', 'r', '1993', '7195', '5299', '761', '1639', '5409', '4455', '7723', '765', 'k', 'v', '8063', 'u', '693', 'w', 'v', 'j', 'u', '6595', '7283', '6593', '3439', 'u', '3731', '4143', 'r', '8477']

c, g, j, k, n, o, q, r, t, u, v, w, x