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: ['41', 'o', 'm', 'h', 's', 't', '407', '445', '371', '93', '291', '457', 'r', '391', 'a']

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

PROBLEM: ['357', 'c', 'f', '3', 'q', 'w', 'm', 'l', '137', 'k']

SOLUTION: 1, 3, 5, 7

PROBLEM: ['95', '71', 'c']

SOLUTION:
1, 5, 7, 9