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: ['y', '281', '313', '21', 'i', '377', 'e', '111', '71', '231', '409', 'k']

SOLUTION: 0, 1, 2, 3, 4, 7, 8, 9

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

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

PROBLEM: ['p', 'v', '175', 'h', 'f', 'b', '281', 'l', '105', 'd', '361', '493', '287', '483', 'e']

SOLUTION:
0, 1, 2, 3, 4, 5, 6, 7, 8, 9