exit退出ipython

进入homework_9文件夹

ipython3  # 打python3交互环境

res = 2**112 + 3**78

! echo $res > ans.txt  # ! 表示后面的内容是shell脚本

cd ~/homework/lesson_7/homework_8

tar -zcvf project_a.tar.gz dir_a
tar -zxvf project_b.tar.gz

cd ~/homework/lesson_7/homework_7

# 用 cut 把文件中空格后的部分去掉
md5sum scores.txt | cut -d ' ' -f 1 > ans.txt

cd ~/homework/lesson_7/hoemwork_6

head -5 scores.txt > top.txt
tail -4 scores.txt > bottom.txt

cat scores.txt | cut -d ' ' -f 1 | sort > names.txt

cd ~/homework/lesson_7/homework_4

cat scores.txt | cut -d ' ' -f 1 > names.txt
cat scores.txt | cut -d ' ' -f 2 > mathematics.txt
cat scores.txt | cut -d ' ' -f 3 > algorithm.txt

find . -name '*.py' | xargs rm

注意ag和grep的区别是，ag不会区分大小写

cd ~/homework/lesson_7/homework_2

find . -name '*.cpp' | xargs cat | wc -l > ans1.txt
find . -name '*.py' | xargs cat | grep thrift | wc -l > ans2.txt

进入homework_1文件夹；

[1] 添加可读权限：

chmod +r * -R

[2] 统计行数:

find . -name '*.cpp' | wc -l > ans.txt

1.cd homework_0
2.vim mydu
3.代码

#! /bin/bash
du -h
4.chomod +x mydu
5.vim ~/bashrc
6.在最后一行添加

export PATH=/home/acs/homework/lesson_7/homework_0
7.source ~/.bashrc