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: ['c', '435', 'c', 'q', 'u', '191', 'b', 'l', '217']

SOLUTION: 1, 2, 3, 4, 5, 7, 9

PROBLEM: ['k', 'b', 'k', 'l', '441', 'b', '115', 'd', 'b', 'r', '115', 'k', 'a']

SOLUTION: 1, 4, 5

PROBLEM: ['153', 'b', 'k', 'f', '125', '215', 'u', '487', '369', 'z', 't', '307']

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