通过设计、编制、调试一个典型的语法分析程序，实现对词法分析程序所提供的单词序列进行语法检查和结构分析，进一步掌握常用的语法分析方法。-A typical parser through the design, development, debugging, syntax checking and structural analysis of word sequences provided by the lexical analyzer, and further understand the syn