A few humble suggestions

[Salil03]

First of all, I would like to say that yours is one the best competitive programming books I have seen. Keep up the good work!

I have some constructive suggestions regarding the book:

1. CSES problem set is necessary but definitely not sufficient for IOI aspirants. It would be very helpful if you add some problems from various sources like Codeforces, Codechef, SPOJ, UVA and IARCS problem archive(Indian IOI program) at the end of your chapter. This would make your book self-sufficient and help the reader in consolidating the section. This is one of the features present in Competitive Programming 3 by Steven and Felix Halim which your book lacks.

2. The sample codes given in the Complete search chapter(Chapter 5) are not clear. If it would not be a bother, can you please consider updating it with a more explicit and better-commented code? It would help beginners in understanding the code quickly. It took me 1 week to understand it.

These are my humble suggestion for a very well written and formatted book. I really respect the fact that you have made the book free and open-source.