Corresponding webpage: http://peportier.me/teaching_2018_2019/ia/dfs/
The source is in a literate programming format. To extract the source from the markdown file dfs.cpp.md do ./mdlp dfs.cpp.md and it will generate the source file dfs.cpp.
You can then compile the source with ./mk1 dfs or ./mk2 dfs. mk1 adds the debugging parameter to g++ while mk2 adds the optimisation parameter.