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]: ['8741', 'h', '2147', '373', 'c', 'r', '2639', '3511', '1393', 't', '7173', 'f', '9371', '7659', 'q', '4799', 'f', '1967', '1905', '8783', 'i', 'n', 'z', '6395', 'u', 'i', '1493', '1395', '1909', '477', 'i', '8547', '393', '2203', '6893', 'y', '2085', '6445', '7753', '4027', 'h', 'y', '7963']
[A]: c, f, h, i, n, q, r, t, u, y, z


[Q]: ['6737', 'g', '9985', '5257', 'k', 't', '7863', 'y', '8319', 'l', 'o', '6505', '6531', 'z', '3055', '2943', '3625', 'h', '4867']
[A]: g, h, k, l, o, t, y, z


[Q]: ['j', '8213', '6247', 'n', '4829', '929', '3031', '9867', 'k', '4981', 't', 'o', '5583', 'm', '4797', '2147', 'x', 'k', 'a', '1513', 'l', '4261', '7537', '885', 'b', 'v', '3661', 'u', '6893', 'q']
[A]:
a, b, j, k, l, m, n, o, q, t, u, v, x