It does seem to be missing quite a bit. I was sure Fenwick had to be there under another name, but I don't see it. Union-find is an even weirder miss, that's a

It does seem to be missing quite a bit. I was sure Fenwick had to be there under another name, but I don't see it. Union-find is an even weirder miss, that's a _great_ data structure and very useful. I couldn't think of any other term it'd be hiding under. The few I couldn't find off the top of my head: square-root decomposition, heavy-light decomposition and really anything at all on Range Minumum Query, one of my favorite general problems (IMO far more interesting than sorting as a group of techniques to focus some time on). > I think this is where I saw union-find: https://www.youtube.com/watch?v=PGZ64ob440I https://www.youtube.com/watch?v=PGZ64ob440I Except I remember a dictionary/hashmap implementation, not a fixed size array. I think you usually see ufds on fixed arrays because it makes the algorithm analysis a bit more interesting. If you have lookups cost more than O(1) I think you'll wash out the fun parts of the analysis. The ds still works well of course regardless.