It's defined in CS50's library; its sole purpose in life is to ask the user for a floating point value and return it.

它被定义在CS50的函数库中，它的唯一目的是,向用户询问一个浮点数的值，然后返回它。

哈佛公开课 - 计算机科学课程节选

The listings at your community center or local library should be able to point you in the right direction.

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Society is rapidly progressing to the point where any Googler is on equal footing with a Widener Library pass-holder.

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The library, which has had extended hours this week (at one point more than 250 users overloaded the WiFi network) and showed back-to-back movies for kids and adults, is back to closing at the usual 5 p.m. today.

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