# Wrap-up The last four exercises that make up {ref}`advanced exercises` and {ref}`expert exercises` are difficult. I chose those tasks because they represent the typical kind of work that I find myself doing whenever I use ROOT: pulling together documentation from different places, translating the examples into the work I'm actually doing... and pounding my head against the desk whenever there are no comments, or I get yet another segmentation fault.[^f148] If you'd like to see how I solved those exercises, you'll find my code in PlotGraphs.C (for exercises 12-14) and MakeNtuple.C (for exercise 15).[^f149] Good luck![^f150] :::{figure-md} computer_problems-fig :align: center xkcd computer problems by Randall Munroe ::: [^f148]: Now you know the reason for my going bald! [^f149]: Maybe you're thinking, "Wow! It's lucky I went to the end before I started doing any of this stuff!" Take my word for it: reading my solutions is not a substitute for working through the problem yourself. For example, I wrote those solutions in the mid-2000s. Since then there have been improvements in ROOT, C++, and Python. You can do better than I did! [^f150]: Total lifetimes used up: up to ten, depending on if you chose to learn both ROOT/C++ and pyroot, which tangents you took, how much LaTeX you learn, if you read the {ref}`section on statistics `, and whether you choose a career in physics. I generously give any remaining lives back to you.