What Are the Key Lessons to Take Away From the Algorithms Library?

I think the right thing for something like flat map well let me back up so what I'm talking about in particular is flat map because it's just you know cloning most of the interface of map. It has things like insert it has in place it has the square bracket operator it has try and place it has blah blah have all these different things if you boil it down it's just try and place but that begs the question if we have map flat map multi map flat multi map I guess the on-order ones don't quite work the same. If we want to make your own map like type you only have to define 10, 12 functions instead of like literally I think for stood vector which