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: ['445', '91', '141', '185', 'b', 'k', 'f', 'l', 'i', '229', 't', 'v']

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

PROBLEM: ['p', 't', '211', 'r', '439', 'h', 'g', 'c', '299', '371']

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

PROBLEM: ['y', '487']

SOLUTION:
4, 7, 8