I've been grinding 1900-rated problems lately and got completely walled by 1909I.
https://codeforces.me/problemset/problem/1909/I
I spent way too much time on it, finally checked the editorial and the solution involves advanced polynomial tech like NTT. I checked clist and it's rated around 4000.
Is the rating just completely bugged? If so, admins please fix it. But if the 1900 rating is actually correct, could some high-rated coders explain the simpler way to think about this?
Thanks!
Rainboy does it. Gets rated 1900-2000.
but he didn't solve it in the contest, but after. And it also had no solves during the contest, it doesn't actually seem to be a 1900~2000 rated problem.
Nah man, it's basic knowledge
Seems to pretty clearly be a bug. It's not even a rainboy issue; rainboy didn't actually solve it until after contest. Based on the standings, it had no solves during contest, so it surely cannot be below 3500.
Allegedly rainboy upsolves have caused rating bugs in the past? Source: https://codeforces.me/blog/entry/126799
Also I'm doing the same thing, grinding slightly easier problems to practice speed and implementation. But the 1600s and 1700s don't feel that much easier than the 2200s and 2300s I practiced with. They're definitely easier since I get them almost all the time vs ~60% success rate with the hard ones, but it feels like half the time they're easy and the other half they feel almost as hard as 2200s. Am I going crazy or do you feel the same way
It was solved by zh0ukangyang, who was banned and hence had rating 0.
I mean it's a 1909 problem
Because apparently the problem is well known in china