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:
['w', '13', 'b', '455', 'b', 'k']
answer:
1, 3, 4, 5


question:
['y', '281', '313', '21', 'i', '377', 'e', '111', '71', '231', '409', 'k']
answer:
0, 1, 2, 3, 4, 7, 8, 9


question:
['437', '171', 'z', '91']
answer:

1, 3, 4, 7, 9