Tutorials

Linux: How to use ufw to block visitors by country?

Learn hot to block users by country or region on Linux using a list of IPs.

MySQL my.cnf recommended optimization

MySQL configuration by default comes with general configuration that can be optmized for specific configuration. Most of modern server configuration should be changed to improve performance. In this brief tutorial we explain how to improve performance by tunning my.cnf configurations.

How to Install aircrack-ng on Debian Linux?

How to install lastest aircrack-ng version on debian linux or in any linux distribution (compilation from official source code)

Python: How to Parse String to a Number (Float or Integer)

We explain how to parse numeric expression like 3.144 to float or 42 to intefers using python.

Which is the proper way to compare strings in Java?

When comparing string in java you could get confused with unexpected result using ==. Should you use equals() in java to compare strings?

How to Redirect using HTML

To redriect using HTML add a meta with the desired url. Check here for more details

Python: Recursive File Search in Directories

How to search files and directories using python (recursively file search with python). Code examples for python 2 and 3.

How to write IF...THEN in an SQL query? (sql server)

In this tutorial we are going to explain how to wirte an IF...THEN statement with SQL Server. We use the sql standard CASE and also explain the IIF statement.

CloudFlare: How to log original IP with nginx

Analysis of travel salesman problem

Travel salesman problem (TSP) is a very well know computer science problem which is really easy to understand but it's a NP-hard problem. The problem is about finding te shortest possible route that visits each city and returns to the origin. Here we analyze the problem and variants of it.