shell编程

https://www.runoob.com/linux/linux-shell-basic-operators.html
https://www.runoob.com/w3cnote/shell-summary-brackets.html

//for循环
https://www.cnblogs.com/dylancao/p/9516462.html

//博主
https://www.cnblogs.com/lottu/category/470144.html