Lexical analysis of the main tasks are: to scan source code character by character from left to right, resulting in one word (Token), also check the source of lexical errors.

词法分析的主要任务是：从左到右逐个字符地扫描源程序，产生一个个单词(Token)，同时检查源程序中的词法错误。

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We need to check another entrant from the outside, left wing or right wing, we need to check another entrant in the middle, there is only one possible one there, and there's a third kind of deviation we should check, what's the third type of deviation?

我们需要验证另外一个外部的参选人,左派或右派,我们需要验证另外一个中间的参选人,只有一个可能参选的人,还有第三种要验证的偏差类型,第三种偏差类型是什么

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