let usage method [email protected]:/tmp# n1=5
[email protected]:/tmp# n2=10< br />[email protected]:/tmp# let result=n1+n2
[email protected]:/tmp# echo $result
15
[email protected]:/tmp# let n1++
[
Tag: method
Regular expression – what is the fastest way to determine the full URL from a relative URL (given basic URL)
I am currently using the module URI::URL to generate a complete URL from a relative URL; however, it does not run as fast as I hoped. Does anyone know of another approach possible Will be faster?
Regular expression – What is the best way to make a string operation in a shell script?
I have a path as a string in a shell script, which can be absolute or relative:
/usr/userName/config.cfg< /p> or
../config.cfg
I want to extract the file name (the part after the
Automatically install Linux system method one:
1, yum install -y system-config-kickstart
2, system-config-kickstart Execute a graphical tool for generating answer files
3. Automated installation is based on network installation, and
LINUX Under Construction of iSCSI Sharing Storage LINUX-IO Target mode DEBIAN9.5 implementation
The iSCSI (internet SCSI) technology is researched and developed by IBM. It is a SCSI instruction set for hardware devices that can run on the upper layer of the IP protocol. This set of instructio
SED practice, some SED common methods
1. Copy the /etc/rc.d/rc.local file to the /tmp directory, and copy the
Add # at the beginning of lines that start with at least one blank character. sed -ri’s/^ +/#/g’ rc.local 2. Copy /bo
Forest Program (DFS Method — Ring on Tree)
The meaning of the title: Every connected block in the desert is a cactus; a connected block is a cactus if and only if there are no heavy edges and self-rings in the connected block , And each sid
Linux server View whether PHP supports mail () function method
PHP’s Mail function can be used to send emails. For example, check whether the Linux server PHP supports the Mail function?
How to check whether PHP supports the Mail function
There are
String.getBytes () Chinese code problem
Get a byte array in the default encoding format of the operating system. This means that under different operating systems, the returned things are different!
byte[] a = “中”.getBytes()
[Data Structure] Big Data Processing Interview Solution
The idea of big data processing is generally like this: Divide a file that cannot fit in the memory into small files according to a certain method, and then see if there is a suitable data struct