Notepad++ is a free (as in "free speech" and also as in "free beer") source code editor and Notepad replacement that supports several languages. Running in the MS Windows environment, its use is governed by GPL License. So compiling it on Linux is very hard. Notepadqq is a free and open source alternative to Notepad++.
To add this PPA to your Ubuntu distribution and to install Notepadqq, simply run the following commands:
|$ sudo add-apt-repository ppa:notepadqq-team/notepadqq
$ sudo apt-get update
$ sudo apt-get install notepadqq