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: ['73', '215', '389', '381', 'e', 'v', 'j', 'l', 'r']

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

PROBLEM: ['h', '27', 'o', 'm', 'i', 'b', 'i', 'k']

SOLUTION:
2, 7