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: ['p', 'g', 'q', 'e', '8045', '9999', '9555', '7995', '7195', 'z', 't', '5223', '3699', 'i', '4797', '3817', 'x', 'y', 'w', 'o', '8915', '7803', 'n', '1117', 'c', '9647', 'p', 'e', '9669', '4845', '9255', '4545', '3693', '6871', 'w', '4327', '3285', 'k', 'f', 'x', 'i', 'b', '5967', '6601']

A: b, c, e, f, g, i, k, n, o, p, q, t, w, x, y, z
****
Q: ['8235', 't', '1695', '9899', '3633', 't', '1823', 'r', 'x']

A: r, t, x
****
Q: ['2637', '6929', '7671', 'k', 'w', '3031', '1939', '523', 'p', '5415', 'n', '6477', 'x', '3777', 'w', '3377', '5391', 'n', '9395', '7661', '6759', 'j', 'l', 'f', 'b', 'y', 'v', 'x', 's', '8541', 'w', 's', '7155', '7977', 'i', '1607']

A:
b, f, i, j, k, l, n, p, s, v, w, x, y
****