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]: ['c', '1693', 'l', 'u', 'x', '3609', 'h', '4159']
[A]: c, h, l, u, x


[Q]: ['y', '8115', 'f', '5333', 'f', '3437', 'b', 'e', '5719', 'm', 'w', '95', '4863', 'k', '4895', 'a', '8179', 'm', '7919', '1731', '229', 'r', '1847', '7559', '6669']
[A]: a, b, e, f, k, m, r, w, y


[Q]: ['l', 'g', 'h', 'u', 'm', 'r', '361', 'l', '7765', '1121', 'b', '9447', 't', '5797', '6305', '1555', 'q', 'c', '2345', '2799', '6393', 't', 'e', 'h', 'v', 'i', 'h', 'p', '111', 'o', 'g', 'l', '7101', 'r', 'y', '9817', 'm', '2761', '7141', '9603', '9035', '8573', '3243', '9447']
[A]:
b, c, e, g, h, i, l, m, o, p, q, r, t, u, v, y