edit: Oops! I just realized I posted this in the wrong chapter. I was working on chapter 20’s challenge
I was relieved to have a more straightforward challenge this chapter, however I noticed something when creating the new class. When I created the subclass this time Xcode put it in a sub-folder with main.m (see image below) instead of the top level like when I created the BNRStockholding class (or like with the BMITime program). Everything seemed to compile and work fine this way, my question is simply why was it created here instead of at the top level like before and is it just a matter of personal organization preference or are there issue that could arise from putting your class files in the wrong location?