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]: ['w', '1349', '3393', '7507', '2469', '8531', 'w', '6845', 'k', 'q', '2401', 'f', 'g', 'l', 'n', 'n', 'e', 'q', 'y', 'v', '3077', '4167', 'b', '5517', 'b']
[A]: b, e, f, g, k, l, n, q, v, w, y


[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']
[A]: c, d, e, h, i, k, p, q, r, s, t, v, x, z


[Q]: ['g', 'h', 'l', 'c', '9927', '741', '5331', 'p', 'q', 'q', '2433', '7607', 'a', '1155', '1597', '6801', 'f', '741', 'g', '2321', 'k', '6441', '6069', 'z', '2773', '8629', '579', 'o', 'l', '8079', 'o', 't', '3429', '5835', 't', 'b', 'y', '1463']
[A]:
a, b, c, f, g, h, k, l, o, p, q, t, y, z