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:
['a', '55', 's', '71', '271', '211']
answer:
1, 2, 5, 7


question:
['y', '483', 'g', '427']
answer:

2, 3, 4, 7, 8