四则运算器

1.实验目的:

学习Yacc——编译器的生成器的基本使用方法。使用bison（和YACC兼容）实现一个中缀表达式四则运算的计算器。

2.实验步骤

一.阅读《Lex和yacc工具.doc》和《Lex和Yacc简明教程.pdf》-four arithmetic unit 1. The experiment : Learning Yacc -- the compiler generator use of the basic method. Bison use (and compatible with YACC) to achieve an expression which is made up of four computing calculator. 2. An experimental steps. Reading "Lex and generates tool. Doc "and" Lex and Yacc Concise Guide . pdf "