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: ['k', 'a', '437', '461', 'b', '341', '175']

SOLUTION: 1, 3, 4, 5, 6, 7

PROBLEM: ['u', '465', '129', 'o']

SOLUTION: 1, 2, 4, 5, 6, 9

PROBLEM: ['93', '43', '467', 'g']

SOLUTION:
3, 4, 6, 7, 9