Knowing how to implement sort does not mean you can't do higher complexity things. These are not the basics of programming, I think. Someone the other day refused my candidacy just because I was unable to comment more broadly on the abstractions used in C# async library, which is completely off the point. If you need to do some tweaking on async, you go to microsoft or google and find it out. Most of the time you just need working knowledge of how to use async await and a few other things.