一个控制台中缀表达值求值程序，相当于一个科学计算器。只支持四则运算，不能纠错。数据结构必备。-A console infix expression value of the evaluation procedure, the equivalent of a scientific calculator. Only supports four operations, not error correction. Data structure is essential.

简易科学计算器,采用控制台编程.支持各种运算符-Scientific calculator, using the console programming support various operators.