We are glad to invite you to participate in Codeforces Round #449 (both Div. 1 and Div. 2) which will be held on December 2, 17:05 MSK.
There are seven problems, created by webmaster, ODT, dogther.
This round is about the happiest girl in the world — Chtholly Nota Seniorious~!
You will help Chtholly, Nephren, Ithea and Willem (characters in the great novel and anime "What Do You Do at the End of the World? Are You Busy? Will You Save Us?") to solve some problems.
(Image by gin_sei56(・.8・) on pixiv)
This round is our first round on Codeforces.
Thanks to zcyskyaa for helping us, Arpa, cyand1317 and Tommyr7 for testing the round, vintage_Vlad_Makeev and KAN for round coordination and MikeMirzayanov for Codeforces and Polygon platforms.
This round has 5 problems in each division and you have 2 hours to solve them.
The scoring will be announced shortly before the start of the contest.
The contest is rated for both Div. 1 and Div. 2 contestants.
It's recommended for both divisions to read through the Interactive Problems Guide before the round.
Wish everyone high rating and accepted submissions!
Upd: Scoring is 500-1000-1500-2000-2500
Upd2: Congratulations to the winners:
The editorial will be posted soon.
Auto comment: topic has been updated by ODT (previous revision, new revision, compare).
I would solve 2E if there was a little more time
The experience is so bad :(
Problems are really good
Hope there is no long queue next time
Looks like an interesting round!
I agree with you.
Is lxl rated?
I feel that the round will be rated
Too lazy coders use bits!
Ohhh bro, First of all, check it for "Is it DATED" !
However,the round is semi-rated.lol
Sounds like a poisonous round.
I think Round#447 is more poisonous! QAQ
Really? Round #447 is interesting and fun,isn't it?
Not at all...Solution for Div1E is just string divide and conquer then generating function and FFT
lxl leaked it before the contest and said you can't solve it even if you know the problem
UPD:This poisonous round must be unrated!
Maybe only students from NS can solve this problem!
As a tester, just joking.
In fact, I think the problems are okay as a codeforces round.
But in China, lxl (ODT 's Chinese name) is considered as a problem setter of the most difficult and troublesome problems.
And many contestants are afraid of lxl, and always think that his problems are bad. I just want to say that, the contest is quite good, and lxl and the others authors work very hard to make a good contest!
Wish you have fun in the contest!
See you all!
Chinese CodeForces div1 rounds' difficulty is above average anyways
Nope Nope Nope Nobody's gonna AK this Chinese round.jpg
Chinese CodeForces div1 rounds usually have less hacks， so I dislike them.
Why it isn't in the main page? UPD: It's now :D
Chtholly is good!
The happiest girl in the world!
Wish everyone enjoys the round and few bugs! And hope all the programs will be fast in practice :D
Chtholly is invading Codeforces... And, I really don't want a math contest! PLS!
It surely won't be a math contest. It might be a Data Structure contest, I suppose.
No tricks please
Where can I find these pictures?They are very interesting!
Auto comment: topic has been updated by ODT (previous revision, new revision, compare).
Auto comment: topic has been updated by ODT (previous revision, new revision, compare).
ke jiao xing guo(
The girl on the picture is not Chtholly :(
Interactive Guide — Div 2 I am comming back :D
Hope not to meet five data structure problems...
Hope not to meet five data structure problems, too.
Hope not to meet five problems with block dividing algorithm, too.
Data Structures Round? Very interesting! But I hope there will be less data structures problem. :)
I know you are good at solving data structure problems! Aren't you?
I agree with you.
I can't read the annoucement again...
Check your internet connection! XD
I mean,I have no bravery to read it again:(
Is Chtholly rated?
Dear ODT, why not to darw chtholly with me? It will be fun, my dear friend!
Some interesting IDs belonging to ODT upvote this annoucement...
But I prefer to practice FalunDafa rather than take part in this round!
В конце концов, Чжэнь Шань Жэнь это единственный критерий для оценки хорошего или плохого человека.
Chtholly is good! hope the contest will be the same as usual. also hope everyone high rating!
Could you resize the image to be a bit smaller? It looks really weird on the front page.
DULIU mcfx HENTAI lxlI will never participate in a DS round! (emmm... and I advise ODT to prepare for National Higher Education Entrance Examination in a hurry (wu
lxl :I can pass the exam easily and taking lessons does nothing to me!So I will make more DULIU problems to make money!(:
Chtholly Nota Seniorious!
orz krydom ,upstairs ↑.
Chtholly Nota Seniorious
I think this contest will be very interesting!
But "Is Chtholly rated?"
another weeaboo garbage jesus fuckign christ what happened to this website
No, we practice Falun Dafa, we are real and kind and forbearing.
The police is coming for you.
Let them come. A real Falun Dafa studier is not afraid of commies.
I guess you'd better shut your f**k**g Falun mouth before you attract more police to our computer room.
You d***less person get away
Don't be so rude, my friend :)
Yes, at least we are all anti-commies.
zcy!!! is he the man who has hung and beaten the trained team ? %%%%
I like this round of contest
I think too many big images and words in animes appearing in the contest will make me feel #%#[email protected]^(&#! when I solve problems.
I hate people who put big image of Chtholly everywhere!
Not so big. KAN will sure that the image in a small size :(
ODT YOU NOT YELLOW MATE
Does that mean he can't be a good problem setter?
By the way, ODT is very excellent!
Love this Anime and LN so much :> Hope everyone high rating and have fun coding :>
Looking forward to such a 'colourful' contest!
Well, except troublesome Data Structures.
Uh, I'm wondering if there will be big pictures in desciptions of problems.
This picture is really nice. I wonder where do you find it.
this picture is famous, dont't you know? Use baidu before asking! ( www.chtholly.ac.cn is also a nice choice!) :)
well, I didn't find the picture above on baidu indeed.
cyand1317 confirmed there won't. Thanks cyand.
So after consideration and discussion, we've reached this decision.
There won't be large, distracting images. Some problems contain smaller images that may act as a delimiter, though — start reading the statements after the image if you'd like to.
I agree it's the best decision about images in problems. I'd like some lovely images and decriptions or scripts about animes, though. Therefore, I can decide if I'm interested in that anime and whether to see it later. However, many feel sick about images of cartoons. I suppose this is the best balance, making ODT able to share and express, while not disgusting others. Anyway, lxl just can't help putting his beloved into problems.
Wanna know if you'd like that anime? Go to MAL, not cf.
I like some anime, but I don't want it mixed into problems.
It's like saying, "wow I like soda, gonna make some soda-flavored pasta :D"
Again these shitty anime pictures covering the whole screen...
Yet another anime round,but with DULIU problem setters...
But cheerful with Chtholly :)
I think its not good to use Interactive Problem because many Div. 2 contestants. don`t know it for me i didn't see it before
So why don't you go through the interactive problems guide as suggested in the blog?
I did but i suggest it will be good to use it in educational round or unrated one
This might be harsh — but you are not going to solve anything and improve with this attitude.
So what is your suggestion ?
Solve an old interactive problem if you don't feel confident.
I love these anime rounds :D
I also like animes
Wow anime round ! what could be better!
Wish round will be without system errors! And of course, wish problems will interesting and enjoyable ...)
lxl(aka. nzhtl1477, ODT) is really a toxic tumor!
Oh look, another anime that every weeb have watched it except me. Somehow people really like to recommend this anime but I am so triggered by it's title so I skipped it because of it's title is literally longer than my cumbersome comment.
PS: Weebs are taking over ICPC in EC in case if you don't know
(full login password: I love Megumi, Google Megumi Kato)
Pffft, Megumi from konosuba is wayyyy cuter. EDIT: Oops, this is Megumin not Megumi. Sorry.
Except this is Megumin.
'n' is often added to Japanese names to make them cuter.
Which means megumin is cuter than megumi >:D
Hope everyone will have fun with Chtholly in this round~ P.S. I love Nephren forever!
When there will be a "Nephren Round"?
I like this contest! Maybe I'll participate in it.
Maybe Chtholly will get high rank in Chtholly round
Not maybe, It should be: "must be" :P
You did it and done great ... congrats !!
The amount of discussion on this thread is growing faster than exponential running time! :O
Yeee, anime round, we all were missing it.
An anime round?
Or a lxl data structure round?
This won't be a lxl data structure round.
On one hand, data structure problems are nice, but on the other hand, we have interactive...
Hope the network is good tomorrow. The server was down for several times this week.
How to solve D? I used binary search + FFT but it was TLE.
You need to use online dynamic persistent red-black tree with square root decomposition + some dp optimizaton + FFT
Thanks a lot. I finally figured out the TLE test case of my solution:
But seriously, why most of light novel need to have a ridiculously long title? This, Moshidora and Oreimo each seems like they have about 50++ characters in their title >_<
So 51 characters?
nah it returns 50.
you were right
V I R A J
M A D D U R
It seems to be an unsolvable round?
Five difficult data structure problems!
这这这……what is this? 好像混进了什么东西。
How to solve Div1 A? I code for 10KB but got WA.
You only code for 10KB? How could you do that?
What? How can you solve it within a 10Kb-code? I have code 30Kb but I haven't finished it yet! :(
What makes you sure that you can solve it within a 10kb code,bro?
Beacuse I think it's Div1 A, so I think the code won't be too long.
Have you forgotten who are the editors of this round? XD
Wake up mate, it's ODT's problem, the code can't be short.
Oh.. I forgot the editors of this round! thx bro, I will recode soon! :)
But I wrote a 5KB code and got accepted :)
You are so strong :) I have just complete it in 35Kb. (QAQ)
In fact, I missed a 0. So it is 50KB :)
But you got AC.
I got WA199 at last :(
I lose hope on recoding :( It's too long..
Why not try to get the answers with a Brute force and just print the answers for each tasks? Certainly you need to beg others in your room not to hack you XD
An FST will be ready for you :) You know, those problem setters are hackers :)
Oh no I hope that setters are lazy and just made weak data,though I'm sure that is impossible. :(
You can submit it at the last second so that no one can hack you.
Oops, Problem setters can :)
I got accepted and the time complexity is only O(logn) !
How to solve Div.1 F? It's a challenging problem with a 30s time limit. :(
Wake up bro, the article has said : This round has 5 problems in each division and you have 2 hours to solve them. No problem F in Div1 :)
I know that :) So why is there an F? emmmmmmmmm maybe a DULIU problem setter?
Maybe an extra problem. So you can imagine how difficult it is...
What means 'DULIU'?
There are many kinds of DULIU problems,such as:
The author's solution runs 0.9s,and the time limit is 1s.
The author uses 5 hours to write the solution and the length of the contest is 3 hours.
The author uses some strange algorithms to solve the problem.
DULIU (毒瘤) means tumor in Chinese
It refers to those problem setters who set up exceedingly difficult and troublesome problems, thus making most problem solvers revolted so that they can't help complaining that the problems and their setter are really DULIU.
If you can solve all the problems and the total length of the codes is less than 50kb,you can see the Div.1 F.
How to sovle Div1C with block dividing algorithm? I got TLE over and over again.
std::bitsetand do some constant optimizations.
Observe in the dark
Let's wish Good Luck codeforces servers)
CONTEST: Omae wa mou shindeiru!
What's up with this weird discussion going on? Is ODT bad problem setter? Can you guys link me to some of his contests? This is really interesting.
if u r a true anime fan u should watch boku no pico great anime with intresting plot
yoooooooooooooooooo I'd NEVER watch that! It's revolting. I'd like lovely Chtholly better.
I can confirm this is true, I've watched that many time before. 10/10 would watch again though.
P.s: Pico best girl.
Every 3rd round on codeforces since I have joined is unrated due to some tech issues. I am scared today :p
The queue is insane.
Long queue for anyone else?
I just waited for an hour and got a WA.
welp, guess i'm doing something else of my afternoon than a codeforces round...
Lol this will probably be unrated
6-minute-queuing (until the moment I write this comment). Last time I started to complain about queuing issue, it subsided a few minutes later. Hope it will work this time as well :<
I've submitted a code with 22 minutes. No response yet. So, I it's a 16min+ queue time.
Well this is starting to get ugly...
30+ pages of queue? How is anyone supposed to time manage like this :/
My submissions can't even pass "pretest 1", because they TLE on "in queue"
37 pages queue...
No server problems so far but the queue is just as bad!
In queue = unrated pls
Long queue. Submitted B 20 minutes ago and still no verdict
Submitted B 20 minutes ago and only now I get a response that I missed it. This is pretty unfair and I request it becomes unrated.
time to wait another 20 minutes to see if I got it
The math says system testing will finish before pretest :-P
Seems fair that chtholly might win the contest
nearly 40 pages queue, should I continue the contest or not? :P
I'll go watch WorldEnd while waiting for the queue .__.
The nice problemset was simply ruined because of the queue :/
Unrated again ?
Maybe unrated Sad :(
What are you doing at the beginning of codeforces round449？ Are the judger busy？Will it judge our submissions of this contest？
After 40 minutes I got my verdict Wrong Answer ! And after re-submitting when I will get my verdict ? After the contest ends?
I submitted 1st question in 9 min and got a score of 488 and after 2 min it was reduced to 428. Can anyone explain why? All the pretests passed and the total score was still 470 and yet they gave me 428?
Your solution got submitted twice. Even if pretests on the first submission pass, it is counted as 1 penalty.
I won't save a poisonous problem setter even if I'm not busy at all ：（
Dear codeforces, please hire some good engineers . those who can manage your servers
Did you know that 55 is not only the fifth palindrome number with 2 digits, but it is also THE NUMBER OF PAGES IN THE QUEUE?
I just waited 30 minutes to find wrong answer verdict
Oh this is just great. (35 minutes waiting for that verdict) And also this one. "Working on"? — I guess it should be an unrated announcement instead...
UPD: Seemed like many people's opinions are going to the void.
Waiting for round getting declared unrated and Mike's apology blog
Was testing system replaced by a group of Chinese? :)
Btw, problems are very good.
problems was good ? oh man are you kidding ? problem C / Div2 , A / Div 1 was good and beautiful ?
Not beautiful, but good. B and C are better than A(div1).
It's just my opinion.
I got a friendly advice to make a standalone blog instead, but couldn't delete the original message, because it was too old.
I think we will need BigInteger queue, because long queue will overflow :'D
It seems to be unrated :(...So sad to hear about it...
The announcement should be "This contest is unrated!"
I have lost hope to solve the problem. Because of [unsigned long long] queue and the HARD problem(Div.1) :(
But, it seems to be unrated?
And here's another unrated contest -_-
The girl in the post is shedding tears because of the loooooooong queue...
Steelix used unrated attack It was super effective! Togekiss fainted!
i think that the end of the queue is at the end of the world...
Unrated please; the server problems this contest are much, much worse than last contest, and the last contest was unrated, so this one should be too.
It's not the first time such long queues on Codeforces, it's time to buy normal servers. And yes, the round should have been unrated
Dear Mike Mirzayanov,
I think it's time to announce this round unrated because of failing to fix the issue with the judging machine. It's 11-12 pm in some time zone and it's time to sleep if the contest is declared unrated. Thank you for understanding us.
Please unrate it.Getting W/A after waiting for 35 mins straight is just so frustrating.
What are you doing at the end of the queue? Are you busy? Will you test us?
This is my second codeforces round! And I will be unrated until 2018 =)
And you knew that the length of the last line in task C, is equal to the NUMBER OF ASSIGMENTS IN THE QUEUE!!!!!
That wonderful feeling when you submitted your solution about 50 minutes ago and now it gets RE 7. Love Codeforces servers!)
Round extended by 15 minutes? Do you think this will make the round any better?
Maybe he just want to get 15 more minutes to consider whether making this round unrated due to technical problems. :D
Increase the time by merely 15 min and decrease the score like a landslide? I don't think 15 min is enough though ! This has to be unrated !!!
And after all this they extend the contest by 15 minutes!!! Do they still expect to make it rated??? I don't know whether to laugh or cry!!! That's damn funny!
In Educational Codeforces Round 33 (Rated for Div. 2) , I waited for the long queue but that round was still rated.
The queue in that contest was at most 10 minutes (I think), which I feel is STILL fine, compared to today (It's not ideal, but it's manageable). Today, people had to wait for 30-40 minutes to receive a verdict.
Lagforces round #449
I will leave CF if this round is rated.
Still in long queue!! RIP CF
genuine question: What will you do now since the round is semi-rated ?
My rating has been changed, so I leave CF.
What are we going to do in 15 minutes if verdict is given after 40 minutes? -_-
When you are Codeforces, and have a 40+ page queue
It won't be a surprise if the comments on this thread are also queued LOL!
Waited for 25 minutes & got WA
we could use this waiting time for Hacking. _/_ Codeforces.
too hard problems for me
What do you do at the end of the World? Are you busy? Will you save Codeforces?
damn that problem C, I know I did something wrong,but the problem feels really frustrating, like hardcoding,my eyes hurt after reading that statement "will you save us...." also was waiting long long time before verditc came "wrong answer on pretest 5" like , FUCK NO,not attempting that again after 30 minutes :(
Make it unrated...!!
The problems are very good . thanks to the writers . but long queue :(
Dear "whoever decided to extend contest by 15 minutes",
Do you really think that additional 15 minutes would make this competition fair? Or it is just some desperate attempt to make this contest rated?
If it's the first case: - no competition would be far from fair, I've been waiting about half an hour to see that my program does not work. Then I tried to fix something... guess what — I've been waiting another half an hour to see that a bug I found was not the only one. The point is — I should know what I know now max 10 minutes after my first submission (and it was 60, where are my 50 minutes?). My first concern is about amount of additional time. Why 15 minutes seems to be enough to make this contest fair? I don't feel like this is enough. The second thing is what ranking should be — is a person who get accept after X minutes at first try better or worse than person which would get accept after several trials in the first Y minutes (especially for X >> Y)? Because long testing queues affect the second one, but not the first one.
If it's the second case: please don't — just admit that it did not work out, that's what adult people do.
I agree with you, but extending the round doesn't mean they are going to make it rated. I am saying this because, in a very recent contest, there was an extension of 30 minutes (!), but the contest was still declared unrated (for the same reason as today).
Yeah, and the server was faster that day than today ;)
If that's the case, then I'm sorry that I exposed you to my butthurt. To explain myself I can only say that I would bother with extending time iff there is a chance to make it rated. So I assumed that "whoever decided to extend contest by 15 minutes" may have similar approach.
The queue has disappeared... I don't know whether it's a good news or a bad one. Does it mean that the round will be rated? What a sad story... But I do think that a lot of contestants have go to bed after seeing the extremely long queue one or half an hour after the contest began. So do you think it is fair to make it rated?
Although the queues have been cleared but please declare the round as unrated, 1. Some of us waited for long just to get a wrong answer. 2. Many of us lost the hope to continue the contest and hence going by the past trends we already assumed that it's gonna get unrated.
After only 40 minutes waiting only 15 minutes ???
I submitted 2 solutions to problem 1 , in 9 min and in 11 min. Both got accepted and I got a penalty as well. Is it normal in codeforces or there is some malfunctioning going on? Initially I got 488 score and after 2 min it was reduced to 428. Sad :( MikeMirzayanov
there's a 50 point penalty for resubmission
It's normal. There's a 50 point penalty for resubmission regardless of the correctness of the previous submission.
div.2 a,b aren't good for hackers......
This has to be unrated... many people have lost 30+ minutes because they got WA after a super long queue.
What's worse is that resubmitting needs another 30 minutes to get another WA on the same test case. :(
Queue lag + Server lag = Unrated pls?
I even lagged out while trying to post this lol.
I really wonder why CF is not being open sourced ??(it's not a profit making site, right ?) .The website suffers every other round, I'm sure are many people willing to help CF.
Your contest is very stupid please don't repeat this awful... Your problems are unprofessional.
:| why unprofessional ?
if you cant solve them it's not their fault!
And what is a "professional" problem? I know these problems could be improved, but the big issue about this contest was the long queue
MikeMirzayanov Make it rated please ^^
I hope that this round won't be rated. I waited for the result for half an hour,then the Web told me that I was wrong, then I used 1 minute to fixed the bug .But it didn't work again,and I waited for another half an hour. So I used 3600 seconds to fix a bug .Time is money.We shouldn't waste our time. I'm Chinese student ,I have so much homework to do. I tried my best to save time to do the round .If the round will be rated ,not only me ,but also many other people will get very angry. (My English is not good ,I just tried my best to explain my opinion)
Agree with you
When almost everyone asking for an unrated round has performed poorly
I don't know what's worse: The long queues in every other round of CodeForces or the way CodeForces handles these rounds (Extending the round and keeping the participants in the dark about the contest being rated/unrated, and finally making it unrated after the contest ends — A desperate attempt to ensure that the participants take part in the contest and do not leave it midway).
You nailed it! Instead of stopping confusion as soon as possible they prolong it even further.
What are you doing at the end of the queue? Are you busy? Will you test us?
Good problems but awful contest.
what is test 5 for C ?!
D is just https://en.wikipedia.org/wiki/Catalan%27s_triangle + compute binomial for arbitrary modulo.
"How do we make this question harder?"
"Make it modulo anything instead of 1e9+7"
Always work with a charm. (**Smacks my own face for not keeping another combinational template**)
But how do you handle sum from l to r(and C-type customers)?
Fix the number of paying. Sum from l to r is reduced into two binomial terms.
Div 1. A. I wrote a program that kept on failing pretest 1 even though it worked on my computer. What ended up fixing it was doing my preprocessing before reading the input, which should not have changed anything. This issue took me one hour to catch since it took a good 30 minutes for the test results to get back and another 30 minutes for me to figure it out.
How to solve C and E?
On E I had a solution which didn't pass. Did someone pass it with such complexity? Also is there a way to solve it without SQRT decomposition?
PS: I think the round should definitely be unrated, because with such a queue it's not worth looking at the easy problems (Div. 1 A and B) as you may do a stupid bug and then be punished really hard. And so a lot of people start solving the harder problems and the chance of them failing the competition increases (for example I did so — I didn't even read B). Also a lot of people probably gave up after seeing such a queue.
PS2: The people which passed E all have the solution. The constant of my solution should really be large xD
On C operations are random and the queries don't depend on the order of numbers so expect a lot of adjacent numbers to be equal...
msqrt(n)logn + nlog^2n algorithm using binary search tree?
The constant of this algorithm is too big... You can optimize it into O( msqrt( nlogn ) + nlog^2n ), but I think it still wont pass.
for n=1; this is the string "What are you doing while sending What are you doing at the end of the world? Are you busy? Will you save us?? Are you busy? Will you send What are you doing at the end of the world? Are you busy? Will you save us??" and in this string the 194th char is 'y' but in the given test case it is 'b'! please help me if i have build the string in the wrong way please guide me!
You are missing the quotation marks when you reffer to "f(i-1)"
You missed including the quote " right before and after the nested string.
The 194th char is 'b'. There are 218 characters in string f1, so if you start counting backwards from the last character you'll end up at 'b' in 'busy' on char 194. Make sure to count spaces and punctuation as well.
Edit: I think putting in quotations will fix the problem.
Is D all about Catalan number + DP? I regret ignoring an algorithm which computes (nCi mod non-prime for all i) in O(n) time. :/
There is no argument defending that the round should be rated. Please make it unrated as it has affected many of the participants badly.
Unrated please dude
how to solve div2 B
i th number is of format ireverse(i) for example 10th number is 1001
.................... I'm so stupid.......
ME to realized tooooooooooooooooo late
I tried to generate all this "zcy" numbers, but still got WA 3 )) http://codeforces.com/contest/897/submission/32875222
"zcy number" is actually just a positive number, followed by its mirror.
(Like "153351" is just "153" and its mirror — "351")
So you can iterate from 1 to k, generate the zcy number and add its value. Remember the modulo.
Wow, I think this is such a clever idea!! I did not notice this during the contest...
Instead, I used another method to generate the first 100000+10 zcy numbers, and calculate their sum.
when in queue ( but expecting correct answer ) : PLEASE MAKE IT RATED after getting WA : PLEASE MAKE IT UNRATED
after mains when everyone gets WA : PLEASE MAKE IT RATED
It would really be unfair to rate this round because many of us solved the problems faster than our submission times show; many of us submit, wait for a very long time, and find out our submission was incorrect, resulting in us losing more time than we should have. Today, the time lost was significant; some people lost up to 1 hour waiting for submissions. Personally, I lost a total of about 1 hour of time just waiting for the result of my submission (you don't know whether to continue working on a problem or not until you see the verdict), and I'm sure that many other people are in the same situation as me.
In addition, Codeforces Round 445, which happened a few weeks ago, featured servers that were awfully slow, yet still faster than today's. Given that it was still unrated, today's contest should also be unrated.
I got compilation error after waiting for 30 minutes lol
I learned that my solution for div1 A was wrong after waiting in queue for 45 minutes, which was in fact a minor error I made while copying and pasting a lame ass string from the problem set. It will be absolutely unfair if this round is not marked unrated. Adding 15 minutes doesn't reconcile the situation by any means.
how to solve div1 B?
How to handle N > 55 for div1 A/ div2 C? Won't this overflow 64 bit int?
it doesn't matter just take min(size, INF) where inf = 2e18
This is because k <= 1e18
This blog is starting to get downvotes.
I think the problems were good. The issue was in the long queue, so I don't think this blog should be downvoted
Ya except div 1 A/div 2 C, making sure you copied the right string (especially since there are quotation marks) is a nightmare.
Recent weeks I did a lot of work to improve performance and stability of the website. It seems my efforts were not in vain. Today and on the previous two rounds the website worked good.
But today we’ve encountered with long queue because of Codeforces default strategy to rerun each solution if verdict is TL in exclusive mode. On each judging machine there are ~3 invoker services which judge your solutions. Exclusive mode guarantees that at most one solution is currently running. Because of many TLs many judging machine worked de facto in single invoker mode (instead of 3 of them). Sorry for long queue. I effectively diagnosed the issue and temporarily disabled this feature (it will be “on” on the system testing).
Sorry for huge queue. During the round I did a lot of work to understand the reasons. It seems I succeeded in it. I personally promise that after website optimizations (and it seems now it is OK), my next step is to improve judging performance to eradicate such situations.
We decided to make this round rated with weight 0.5 (semi-rated). It means that all rating changes will be divided by two.
Thank you for taking part in the round. And many thanks to the writers and the coordinators!
First time I seen the semi-rated round...:D
Thanks for your great efforts keep up
But there are people who thought according to tradition the round will be unrated so that we can concentrate on other important works(I have Exam ) and left the contest in middle.Please once think about this
It's so called rotten compromise. Nobody is satisfied ;)
If somebody was affected, he definitely wants the round to be unrated and if not, he would like it fully rated.
Mike, this is just not fair. I took off the contest after waiting half hour for a Wrong Answer. Is just ridiculous to think about doing this round rated, please, think again about your decision.