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: ['p', '231', 'd', 'i', '33', '431']

SOLUTION: 1, 2, 3, 4

PROBLEM: ['403', 'j', 'x', '187', '311', 'g', 'z', 'p', '287', 'w', 'k', 'm']

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

PROBLEM: ['103', '431', 'z', '99', 'h', 'c', 'a', '433', '55', 'k', 'a']

SOLUTION:
0, 1, 3, 4, 5, 9