Alright, I'm done. I wanted to write a blog like that for a long time, but now I really don't have enough patience to ignore this issue anymore. I want to say that I get 100-200 clarifications each Div.3 round. It doesn't even matter how well the statements are, it doesn't matter if there are any issues with solutions or checkers, people always find what to ask.
Before I start whining here, I really want to recommend anyone to read these two Um_nik blogs: this one and this one. Sorry, Um_nik, I unnecessarily tagged you, I will not do that anymore. Now some breaking news for most participants: your local IDE compiler and Codeforces compiler are actually different things! If your code works fine locally but gets WA/TL/RE/ML/etc on Codeforces, it (most probably) means you have a bug somewhere in your code. There are rare cases when the issue is with compiler differences, but these cases are really rare. If you have such issue, what do you think you have to do? Of course write a question about that! I got like 50 questions like this on today's contest. It's hilarious. I really suggest you to run your code in custom invocation tab instead of writing a question. If you run your code on Codeforces, you will get the output as it is here and, probably, you will understand what is wrong with your solution.
Also, I got a lot of questions about the problem 1433F - Zero Remainder Sum . Many people were confused if the whole sum you get should be divisible by $$$k$$$ or the sum of each row should be divisible by $$$k$$$. The thing I want to recommend here: read Um_nik blogs. Whoops, unnecessary tag, sorry. To be fair, you could maybe... probably... at least read and understand the first example and the Note about that (the matrix of size $$$3 \times 4$$$, $$$12$$$ elements, come on, it is not hard). If you read that, you will understand that the whole sum should be divisible by $$$k$$$, because otherwise the example answer is wrong. There were no sentences showing that you should consider the divisibility of each row. I make Notes section exactly for such cases (when something can be misleading or unclear). I'm also trying to make examples as clear as possible, to try to cover every possible case that can confuse anyone (this problem was not an exception).
The thing about clarifications that really makes me burn: why do you think that your question should be answered immediately after you send it? The answer time here is not more than $$$5$$$ minutes usually. I heard that the answer time on other platforms can be much and much more than here. Also, please, take in consideration that Codeforces is a huge platform and there are almost 17 thousands participants in the today's round. 17 thousands people versus me and sometimes, maybe, MikeMirzayanov, BledDest or someone else who helps me with questions. When you are spamming something like "why my question is not answered?? please answer!!" you are just increasing the amount of work for me and the waiting time for others. I always answer all questions, you just need to be a bit patient.
About the problem 1433E - Two Round Dances. Yeah, the statement of this problem was really misleading and didn't match the examples, and I'm really sorry about that. We added this problem like $$$2-3$$$ hours before the round start just to smooth out the difficulty curve.
This is pretty old problem that was already partially prepared. I read the statement, wrote the solution and it matched my understanding of the problem. I wanted to write proving naive solution a bit later, but I had too many things to correct in other problems' statements, so I completely forgot to do that. Sorry for that issue, this was my fault.
Continuing the previous paragraph, I want to mention two people (without their handles, it will be obvious to them even without direct mentioning): one guy wrote that "this round is complete disaster make it unrated". I opened his submissions list and saw he solved only A and B. The only thing that could make this round unrated is the wrong statement of E. He didn't even solve C and D. I asked him if the issue with E really affected him when he didn't solve easier problems, but got no answer. The other guy was really rude, and he flamed so much. As the last question from him, I got "what the hell is this there is no mention of rotation in the question. do you realize that?? give you handle i will talk to u later" (this is a citation). I'm really sad about that. I don't understand why some people think they can just talk like that to others.
Some things about previous rounds: one day, I got so many questions if the round is rated or not during the time we were figuring out if we really have to make it unrated. I got something like $$$50$$$ questions about this and just answered "read the global announcement". $$$50$$$ times. I wasted like $$$5$$$ minutes to answer all such questions instead of answering the real ones.
And, in conclusion, I want to recommend you: read Um_nik blogs (whoops). He did really great work about how to read and not to read problem statements. These blogs are a high quality source of understanding how to read and understand statements. Please, read the statement, read the Note, try to figure out the answer on the example, read the global announcement before asking the question. Much question answers can be retrieved from these things. I'm exhausted because of answering questions that are answered in the problem itself (the great example is today's problem C. I got like $$$10-20$$$ questions like "can there be several answers???" but it was bolded in the statement).
I'm done. Thank you for reading if you had patience to read all my whining. Feel free to blame me or something like that, I understand that I'm not perfect and make a lot mistakes.
About English: so many questions have pretty strange English and I just can't understand what are you trying to say/ask. Please, try to make your question as clear as possible, because if you just write some sequence of words and send it to me, I will answer "question in unclear" (after spending like $$$30$$$ seconds trying to understand that) and will wait for the real question instead of the sequence of words without meaning.