乔姆斯基四种文法的判断实现 本代码为未学习语法分析时所写，可以完成简单的给定一部分字符串判断其是否可由该文法推导出来-Analyzing the four grammar Chomsky realized the code for not learning grammar written analysis can be accomplished simply a given part of the string to determine whether it can be deduced tha