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: ['255', '19', '335', '483', 'r', 'c', 'r', 'o', '189', '71', '379', 'l', 'b']

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

PROBLEM: ['173', 'r', 'a', 'n', 'h', 'o', 'w', '135', '321', '59', 'r', '295', 'r']

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

PROBLEM: ['f', 'v', '371', 'r', '171', 'c', '471', '197', 'e', 'j', 'b', '431', '467', '179']

SOLUTION:
1, 3, 4, 6, 7, 9