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: ['93', '277', '373', 'z', '9', 'r', '251', '207', 'v', 'n']

SOLUTION: 0, 1, 2, 3, 5, 7, 9

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

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

PROBLEM: ['e', '131', '295', 'x']

SOLUTION:
1, 2, 3, 5, 9