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 Q]: ['2705', 'n', 'r', '8259', '6839', '3239', 'w', 'z', '2611', '2957', '2303', '6315', '7801', 'c', 'w', 'm', '5049', '6465', '599', 'h', 'q', '7559', 'n', '9917', 'v', 'l', '643', '6415', '3587', 'c', '917', '4435', 'p', 'a', '317']
[EX A]: a, c, h, l, m, n, p, q, r, v, w, z

[EX Q]: ['r', 't', '3539', 'z', 't', '6055', 'r', '5787', '8469', 'p', 'h', '9729', 'z', '1637', '5873', 'c', '3597', '4411', 's', 'k', 'q', '6471', '5375', 'e', 'v', 'i', '7425', 'h', '9079', 'd', '1585', '6011', 'x', '5669', '5219', '4951', '4765', '8285', '2811', 'c', '1805', '6463']
[EX A]: c, d, e, h, i, k, p, q, r, s, t, v, x, z

[EX Q]: ['8907', '5969', 'g', 'e', 'f', 'i', 'j', 'n', 'n', 'v', '8787', 'x', 'u', 'x', 'y', '3275', '7577', 'q', '6801', '993', 'p', '6403', 's', '6255', 'y', 'a', 's', 'l', '3981', 't', '2005', 'q', '1973', 'i', '4337', '7339']
[EX A]:
a, e, f, g, i, j, l, n, p, q, s, t, u, v, x, y