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: ['339', '473', '485']

SOLUTION: 3, 4, 5, 7, 8, 9

PROBLEM: ['455', '447', 'x', '479', 'b', '267', '339', '29', '267']

SOLUTION: 2, 3, 4, 5, 6, 7, 9

PROBLEM: ['427', '23', '385', '135', 't', 'q', 'l', '61']

SOLUTION:
1, 2, 3, 4, 5, 6, 7, 8