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: ['187', '461', 'b']

SOLUTION: 1, 4, 6, 7, 8

PROBLEM: ['401', 'a', '273', 'c', '117', 'x', 'b', 'h', 's', 'v']

SOLUTION: 0, 1, 2, 3, 4, 7

PROBLEM: ['f', 'j', 'k', 'q', 'h', 'j', '39', '257', '297', 'b', '215', '151']

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