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: ['u', '343', '167', 'a']

SOLUTION: 1, 3, 4, 6, 7

PROBLEM: ['h', 't', '371', 'e', '153', 'b']

SOLUTION: 1, 3, 5, 7

PROBLEM: ['103', 'l', '357', 'e']

SOLUTION:
0, 1, 3, 5, 7

