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:
['t', 'v', '469', 'n']
answer:
4, 6, 9


question:
['j', '195', 'u', '55']
answer:
1, 5, 9


question:
['q', 'u', 'f', 'w', 'x', 'b', '463', 'u', '423', '339', '461']
answer:

1, 2, 3, 4, 6, 9