实验要求：



1．单词种别编码要求基本字、运算符、界符：一符一种；标识符：统一为一种；常量：按类型编码；

2．词法分析工作过程中建立符号表、常量表，并以文本文件形式输出；

3．词法分析的最后结果以文本文件形式输出；

4．完成对所设计词法分析器的功能测试，并给出测试数据和实验结果；

5．为增加程序可读性，请在程序中进行适当注释说明；-Experimental requirements: 1. Word kinds of other coding requirements of the basic word operator, delimiter: a character one kind　identifier: unification as a　constant: the type of encoding　Lexical analysis to create a symbol table in the course of their work, often scale, and output to a text file　Lexical analysis of the final results to a text file output　Complete functional testing of the design of lexical analyzer, and given the test data and results　To increase the readability of the program, please make the appropriate explanatory notes in the program　Finishing on the machine steps, sum up experience, and experience　Carefully completed and timely submitted to the experiment report.