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: ['49', 'r', '179', 'h', 'q', 'h', 'w', '187', '427', 'x', 'r']

SOLUTION: 1, 2, 4, 7, 8, 9

PROBLEM: ['109', 't', '283', 'c', 'u', 'y', '251', 'x', '377', 'n', 's', 'd', 't', 'q', 'o']

SOLUTION: 0, 1, 2, 3, 5, 7, 8, 9

PROBLEM: ['k', 'a', '437', '461', 'b', '341', '175']

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