Glancing at the bottom, this is pretty arbitrary, but I chose to format my string as follows: % 1f so at the bottom here I'm printing out %.1f, which quick sanity check means print just one digit after the decimal place.

看下这个底部，这个是相当随意的，但我选择把我的字符串格式化成这样：,所以在这个底部我打印输出，提醒一下，这是一个只打印出,小数点后一位的方法。

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The technique the driver uses to prevent printing is a feature of the PDF format and is really Digital Rights Management (DRM).

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They also point out that new technologies such as print on demand, which makes printing short runs of physical books more economical, should help them squeeze more money out of the old-fashioned format.

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