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: ['215', '391', '251', '177']

Answer: 1, 2, 3, 5, 7, 9


Question: ['71', 't', '267', 'x', 'l', '95', '439', '51', 'i', '497', '469', 'k', '341', 'y']

Answer: 1, 2, 3, 4, 5, 6, 7, 9


Question: ['y', 'w', '379', '463', 'd', 'r']

Answer:
3, 4, 6, 7, 9