说明：  形式语言与自动机讲义（考博必备）。形式语言是研究自然语言和人工语言的数学工具，以状态自动机为基础，建立抽象机器模型。
(Formal Languages and Automata lectures (考博necessary). The form of language is the study of natural language and artificial language of mathematical tools to state automaton, based on the abstract machine model.)