TASK DEFINITION: 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.
PROBLEM: ['51', '461', '343', '15', '209', '51']

SOLUTION: 0, 1, 2, 3, 4, 5, 6, 9

PROBLEM: ['233', '189', '217', 's', '221', 'v', 'c', 'x', '455']

SOLUTION: 1, 2, 3, 4, 5, 7, 8, 9

PROBLEM: ['17', '449', '95', 'b', '401', 'e', 'n']

SOLUTION:
0, 1, 4, 5, 7, 9