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.
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Question: ['k', '373', 'b', '305', 'i', 'n', 'z', 'm', 'c']

Answer: 0, 3, 5, 7


Question: ['f', 'f', '149', '311', '331', 'l', 'u', '349', 'v', 'v', '417', '285']

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


Question: ['477', '437', 'g', '461', 'q', 'h', 'm', 'l']

Answer:
1, 3, 4, 6, 7


