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: ['7', 'n', '443', '131', '189', '187', '261', '451', '449', 'o', 'i', 't', '15']

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

PROBLEM: ['379', '485', '415', '37', '221', '125', '245', '87', 'a']

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

PROBLEM: ['421', '469']

SOLUTION:
1, 2, 4, 6, 9