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: ['k', '107', '333', '317', 'm', 'w', 'g', 'f']

SOLUTION: 0, 1, 3, 7

PROBLEM: ['187', '461', 'b']

SOLUTION: 1, 4, 6, 7, 8

PROBLEM: ['u', 'b', '3', '21', 'e', 'b', 'o', 'd', '417', 'm', '283', '215']

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