实现对C语言的源程序的词法分析的词法分析器，词法分析器的功能就是读入字符串形式的源程序，识别出具有独立意义的最小语法单位，即单词，并对识别出的单词进行相应的产生属性字处理。-Lexical analyzer lexical analysis of the C language source code, the lexical analyzer function is to read into a string in the form of source code to identify the smallest grammatical unit has independent significance, that is the word, and identify words The generation attribute word processing.