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: ['e', '307', '191', 'k', 'o', 'j', '99']

SOLUTION: 0, 1, 3, 7, 9

PROBLEM: ['189', 'z']

SOLUTION: 1, 8, 9

PROBLEM: ['m', '5']

SOLUTION:
5