教师出题，学生进行考试自动给出成绩系统
TIPS:项目时间比较久了，也不再维护了。
对每道试题进行计算难易程度
此代码是历史代码，很多知识点当时认识不是很清楚，代码的风格和模块化比较差，代码质量也不高。仅可参考部分大的框架，代码当时是能够完全运行并无大的错误。
1. 安装mongodb
2. 安装redis
3. npm install 依赖包
3. node app.js
你这个跑不起来啊！！ node app.js 起了服务后，浏览器无法访问啊！！！！
React
A declarative, efficient, and flexible JavaScript library for building user interfaces.
🖖 Vue.js is a progressive, incrementally-adoptable JavaScript framework for building UI on the web.
Typescript
TypeScript is a superset of JavaScript that compiles to clean JavaScript output.
An Open Source Machine Learning Framework for Everyone
Django
The Web framework for perfectionists with deadlines.
Laravel
A PHP framework for web artisans
Bring data to life with SVG, Canvas and HTML. 📊📈🎉
JavaScript (JS) is a lightweight interpreted programming language with first-class functions.
Some thing interesting about web. New door for the world.
A server is a program made to process requests and deliver data to clients.
Machine learning is a way of modeling and interpreting data that allows a piece of software to respond intelligently.
Some thing interesting about visualization, use data art
Some thing interesting about game, make everyone happy.
Facebook
We are working to build community through open source technology. NB: members must have two-factor auth.
Microsoft
Open source projects and samples from Microsoft.
Google
Google ❤️ Open Source for everyone.
Alibaba
Alibaba Open Source for everyone
D3
Data-Driven Documents codes.
Tencent
China tencent open source team.
