国会图书馆是世界上最大的图书馆，它有着最大的目录系统，叫作LOCIS。
The library of Congress is the largest library in the world, and it certainly has the biggest catalog system, called LOCIS.
如果把黄页目录的每年使用数量除以相同大小广告所需费用，就可看到平均花费一块钱，哪种黄页目录能提供最大效用。
If you then divide directories' uses-per-year figures by their charge for the same size AD, you'll see which directory provides the highest number of USES per dollar.
f选项设置高速缓存目录的最大文件数目，按16进制舍入。
The -f option sets the maximum number of files, rounded to the nearest 16, for the cache directory.
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