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: ['h', '475', 'x', '53', '461', 'c']

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

PROBLEM: ['475', '19', 'k', '307', '417']

SOLUTION: 0, 1, 3, 4, 5, 7, 9

PROBLEM: ['317', 's', 's', 'x', 'y', 't', '463']

SOLUTION:
1, 3, 4, 6, 7