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提示：为了方便你定位子任务编号，输入文件中的第一行被额外添加了一个整数，表示子任务的编号。在样例数据中，该编号为 $0$。你可以在附件中找到修改后的样例数据。
Tips: To make it easier for you to get the Subtask ID, an extra integer is added to the first line of the input file to represent the subtask number. In the sample test, this number is $0$. You can find the modified sample tests in the attachment.
请注意你的输出不要包含额外的空行或多余的空格。
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