Meh. Yes, I noticed that I am breaking records on taking very long to finish editorials. I am still having some health issues, unfortunately. I took measures and decided that for SRM 575 the admins should find a replacement to write the editorial :(. I really hope/wish I'll get better for the next SRM.
This problem is nice, it is also something I could have never, ever solved during the contest. I just had no idea of ranks, and I keep forgetting about Gauss elimination.