The guard is used to avoid reprocessing the contents of a header file if the header has already been seen.

头文件保护符用于避免在已经见到头文件的情况下重新处理该头文件的内容。

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The guard is used to avoid reprocessing the contents of a header file if the header has already been seen.

头文件保护符用于避免在已经见到头文件的情况下重新处理该头文件的内容。

youdao