Q: 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.
['327', '271', '255', 'o', '55', '299', '275', 'c', '477', 'p', '81', '237', '235']
A:
1, 2, 3, 4, 5, 7, 8, 9