编译原理资料：第三章，词法分析。词法分析器的设计与实现，正规表达式与有穷自动机，正规文法与正规式，正规文法与有限自动机的等价性-Compiler theory Information: Chapter III, lexical analysis. Design and implementation of lexical analyzer, regular expressions and finite automata, formal grammars and formal style, formal grammars and finite automata equivalence