bianyiyuanli

说明：  一. 实验目的： 设计、编写和调试一个具体的词法分析程序，加深对词法分析理论和自动词法分析工具的理解、实践和掌握。 二. 实验要求： ① 学习和理解正则表达式理论,写出C—语言的记号的完整的正则表达式;(适当使用正则定义) ② 学习和理解有限机理论,根据前面的正则表达式,用基于经验的方法画出C—语言的记的DFA图; ③ 用基于DFA图的算法编写C—语言的词法分析程序; ④ 学习词法分析程序的自动生成工具,使用LEX工具实现C—语言的词法分析程序.
( 1. Experimental goal: The design, compiles and debugs a concrete lexical analyaer, deepens to the lexical analysis theory and the automatic lexical analysis tool understanding, practices and grasps. 2. The experiment requests: (1) study and the understanding regular expression theory, writes the C 鈻anguage the symbol integrity regular expression; (Suitable use regular definition) (2) study and the understanding limited machine theory, according to the front regular expression, with draw the DFA chart based on the experience method which the C 鈻anguage records; (3) uses based on the DFA chart algorithm to compile the C 鈻anguage the lexical analyaer; (4) study lexical analyaer automatic production tool, uses the LEX tool to realize the C 鈻anguage lexical analyaer)