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', 'b']

SOLUTION: -1

PROBLEM: ['415', '365', '373', 't', 'n']

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

PROBLEM: ['f', '87', '301', '337', 'z', 'r', 'k', 'p']

SOLUTION:
0, 1, 3, 7, 8

