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: ['p', 'r', 'e', 'b', '149', '361', 'i']

SOLUTION: 1, 3, 4, 6, 9

PROBLEM: ['h', '281', 'x', '471']

SOLUTION: 1, 2, 4, 7, 8

PROBLEM: ['t', '63']

SOLUTION:
3, 6