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: ['165', '219', 'r', 's', '191', 'k', '39']

SOLUTION: 1, 2, 3, 5, 6, 9

PROBLEM: ['43', '479', '317', 'w', '475', '255', '3', 'x']

SOLUTION: 1, 2, 3, 4, 5, 7, 9

PROBLEM: ['w', 'd', 'e', 'w', '459', '17', 'g', '441', 'z', '473', '167', 'u']

SOLUTION:
1, 3, 4, 5, 6, 7, 9