<!--
 * @Github: https://github.com/Certseeds/CS302_OS
 * @Organization: SUSTech
 * @Author: nanoseeds
 * @Date: 2020-03-23 19:40:01
 * @LastEditors: nanoseeds
 * @LastEditTime: 2020-05-26 11:58:27
 -->
1. use `./baseline ./lab1_user.sh | tee run.log` 
to get best use felling.
2. ./test_case.sh is the shell script to produce paths used to judgement.
3. test_case_2.sh is a easier one that have no answer.ans to diff.
4. ./lab1_user.sh is very dangerous, it use a lot of `rm -r`.
5. 功能简述:实现类似`tree`的功能.