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: ['c', 'u', 'b', '347', '191']

SOLUTION: 1, 3, 4, 7, 9

PROBLEM: ['h', 't', 'h', 'i', 'c', '441', '117', '463', 'r']

SOLUTION: 1, 3, 4, 6, 7

PROBLEM: ['v', '417', '193']

SOLUTION:
1, 3, 4, 7, 9