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:
['51', '461', '343', '15', '209', '51']
answer:
0, 1, 2, 3, 4, 5, 6, 9


question:
['r', '321', '355', 'w', 'm', 'v', 'a', 'u', '455', 'n', '169']
answer:
1, 2, 3, 4, 5, 6, 9


question:
['67', '371']
answer:

1, 3, 6, 7