There seems to be a problem with the code in Chapter 3 in this section where the code example is given for performing pseudo-random traversal.

The values x and y are found using:



but it appears that p ranges from 0 to w * h, so this doesn't make sense for calculating y.

I believe instead it should be something like:

Hmm, I saw that and it seems to deal with a separate bug. Apologies if I wasn't clear enough I was raising a much smaller issue (which I assume is just a misstype) in the code for calculating y.

Though I notice in the link that you posted that the final reply by user ashtorak has the correct calculation so perhaps it is just an issue with my version of the book.