instruction:
In this task, you are given an input list A. You need to extract and sort the unique digits used in the list in ascending order. Return -1 if there is no digit in the list.
question:
['157', 'k', 'o', 'a', '279', 'g']
answer:
1, 2, 5, 7, 9


question:
['175', 'q', 'h', 'z', 'v', 'y', '39', '419', '87', '425', 'z', '375']
answer:
1, 2, 3, 4, 5, 7, 8, 9


question:
['k', '7']
answer:

7