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: ['475', 'd', '467', 'h', 'r', 'r', '139', '307', '141', 'f']

SOLUTION: 0, 1, 3, 4, 5, 6, 7, 9

PROBLEM: ['w', 't', 'a', '199', '385']

SOLUTION: 1, 3, 5, 8, 9

PROBLEM: ['471', '301', '87', 'r']

SOLUTION:
0, 1, 3, 4, 7, 8