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: ['z', '375', 'v', 'o', 'v', '31', 'u', 'x', 'q', 'x', '71', 'n', 'v']

SOLUTION: 1, 3, 5, 7

PROBLEM: ['u', '465', '129', 'o']

SOLUTION: 1, 2, 4, 5, 6, 9

PROBLEM: ['c', 'f', 'h', '329', '9', '249', 'j', 'a', '141', '73']

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