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: ['39', '461', '163', '379', '331', '137', 'g', 'm']

SOLUTION: 1, 3, 4, 6, 7, 9

PROBLEM: ['c', '155', '61']

SOLUTION: 1, 5, 6

PROBLEM: ['333', '399', '77', 'd', 'd', 'k', '265']

SOLUTION:
2, 3, 5, 6, 7, 9