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.

['s', 'c', 'e', '2457', '9413', 'r', '9949', 's', 'z', 'e', 'a', 'o', '7207']
a, c, e, o, r, s, z

['i', '4447', 'g', 'o', 'j', 'p', 'l', 'q', 'o', '8777', 'r', 'v', '961', '6083']
g, i, j, l, o, p, q, r, v

['2691', 'o', '3775', 'i', '1227', 'm', 's', 'w', '9157', '1801', 'j', '4821', '8741', 'l', '269', '505', 'w', 'w', 'm', '13', '4831', '3061', 'a', '5693', 'd', '3507', 'c', 'e', '9863', '1193', '3737', 'h', 'r', '3373', '7401']

a, c, d, e, h, i, j, l, m, o, r, s, w