If you ever decide to abandon C and want to learn a previous-generation Javascript framework (ie. not Angular or React) PM me and I'll send you a copy of my book
[You must be logged in to view images. Log in or Register.]
But back to your book, it seems a lot more likely to me that:
- the book was a textbook for a class, and as soon as someone finished the class they were like "hallelujah" and sold it ASAP without bothering to remove their stuff
- the owner forgot the book somewhere, and when they didn't reclaim it it got sold
- the owner put it with a bunch of other books in a box in their garage or something when they finished it, and then a few years later sold the whole box without checking each book
... or something like that. But people rarely steal computer books, because most only sell for a few dollars, and when you factor in the time to steal and then list it on Amazon/Ebay it's easier to do honest work.