How can I change the default compiler of linux mint 18.0 from version 5.3.1 to a version below 4.0? : I need to compile a special program (i.e. configuring, making, and making install processes of nest) by an old version of g++ such as 3.3 or 3.4. however, I don't have such versions in my package manager. I downloaded g++-3.0-3.0.4-7_alpha-deb, but I don't know if it is the true version for linux, or how can I install it and set as the default compiler. I will appreciate if any one informs me of its possible dangers to my linux (as I read in Google). 

Quick reply is appreciated.