#
Expression Simplify
> You can find the crate on **https://crates.io/crates/expression_simplify**
The program is a Rust library crate in the use of simplifying math expression, its function is based on the HW1 of the first Unit of Object Oriented course of SCSE, BUAA.
> **如何在Rust中实现多态**
>
> * 定义一个trait
> * 为不同类型实现trait
> * 使用特征对象``Box`` 动态指针
* ``version 1.0.0``: hw1