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: ['397', 'x', 'e', '179', '105', '381']

SOLUTION: 0, 1, 3, 5, 7, 8, 9

PROBLEM: ['q', 'a', '149']

SOLUTION: 1, 4, 9

PROBLEM: ['u', '197']

SOLUTION:
1, 7, 9

