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: ['45', 'n', 'u', '199', 'y', 'w']

SOLUTION: 1, 4, 5, 9

PROBLEM: ['425', 'a', '351', 'v']

SOLUTION: 1, 2, 3, 4, 5

PROBLEM: ['u', '73', '97']

SOLUTION:
3, 7, 9