这是编译原理的源代码，涉及到了编译原理的词法分析，语法分析。本实验采用flex和bison工具，编写了一个lex程序和一个yacc程序，实现的功能是对源程序进行词法分析和语法分析，并输出语法分析的过程。-This is source code of principles of Compilers, involving lexical analysis, syntax analysis in principles of Compilers. This experiment used flex and bison tools, a lex program and a yacc program were wrote to implemented it, function of this source program is to analyse source code wrote in C, and output the results.