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: ['o', 'k', 'i']

SOLUTION: -1

PROBLEM: ['361', '47', 'k', '33']

SOLUTION: 1, 3, 4, 6, 7

PROBLEM: ['a', '273', '197', '337', '203']

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