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: ['a', '491', '477', '193', 'b', 'l', 'c']

SOLUTION: 1, 3, 4, 7, 9

PROBLEM: ['483', '409', '129', 'u', '167', '275', 'p', '163', 'r', 'q', 'i', '481', 'j', '271']

SOLUTION: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9

PROBLEM: ['e', 'u', '3', '121', '123', '61', '443', 'w', '267']

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