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: ['437', 'e', 'b', 'f', '203', 't', '5', '461', 'e', '367', '391', '81']

SOLUTION: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9

PROBLEM: ['181', 'n', 'p', '349', '321', '457', 'h', 's', 't', 'k', 'x', 'a', '145', '135', 'u']

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

PROBLEM: ['i', 'j', 'e', '371', '285', 'w', 's', 'e', 'l', 'g', 'r', 'a', 'b']

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