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: ['391', 'y', '447', '345', '157', '265', 'x', '261', 'm', 'f', 'x', 'x', '379', 'r', 'g']

Answer: 1, 2, 3, 4, 5, 6, 7, 9


Question: ['p', 'r', 'e', 'b', '149', '361', 'i']

Answer: 1, 3, 4, 6, 9


Question: ['n', 'y', '1']

Answer:
1