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: ['425', 'x', 'u', 'f', 'v', '481', 'm', 'y', '159', '1']

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

PROBLEM: ['243', '125']

SOLUTION: 1, 2, 3, 4, 5

PROBLEM: ['h', 'f', 'g', 'd', '203', 'f', '207']

SOLUTION:
0, 2, 3, 7