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: ['d', '71', '65', '177', 'k']

SOLUTION: 1, 5, 6, 7

PROBLEM: ['k', 'a', '437', '461', 'b', '341', '175']

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

PROBLEM: ['q', 'm', 'j', '285', 'e', 'r', 'v', 'f', 'n', '35', '279', 's', 'c', '343', 'q']

SOLUTION:
2, 3, 4, 5, 7, 8, 9