Hi, Codeforces!
I have some great news. But maybe you've already noticed? Seen the updated logo?
I'm glad to announce that Telegram is back as our title sponsor. I'm happy, and not just because this means we can keep developing and maintaining the system and (most importantly) running rounds for a long time to come.
But there's something else, too. It was Pavel Durov who, way back in 2010, spent several hours asking questions and trying to understand what I had in mind. Then he put his faith in our community — and Codeforces received support for the very first time. That support helped us for many years. So this means a lot to me personally, and I'm proud that now, more than 16 years after that first conversation, that support is coming back.
This helps with every round we run and gives us a chance to do new things, too. I'm glad to share that thanks to renewed support from Telegram, we've already started moving our infrastructure to a professional data center, making the system faster and more reliable.
I'm sure this won't be the only new thing happening soon. Expect more good news.
Mike
Great :D
Well, Good
This guy is proof of Dead Internet Theory._.
No amount of editing will save your contribution, bro :(
He probably used the ai for more than just generating images
post so shit they had to nuke his account
his/her contribution was so low that his account got disabled xD
Nice
Nice
what about ton?
TON is originally developed by Telegram, but I still don't know why...
Yo, what's up guys? It's me, Bichup Robert Alexander Henry and I'm going to share my opinion. I mean Ton made codeforces very well. This and last years, codeforces has a lot of AI scans, cheater scans and a friendly-user website. So wonder what telegram can do?
I think it is time to add Dark Mode for CF
just put a dark mode extensions from chrome bruv
Extensions generally only support Chrome and Chrome is not a good browser for multiple extensions and multiple tabs,also it is not a very hard feature for vanilla site(I said it 1e9 times but clon CF site has this feature._.)
firefox's got extensions too
Search Codeforces++ on the firefox add-ons website. Adds some pretty cool QoL improvements
May Ada bless your Soul
in 2026
It will be always better to have themes in native to the application. Of course, we can try out extensions or external stylesheets only when native theme selection is not available.
Use Tampermonkey to add the script; it works pretty well with Codeforces.
link: https://github.com/farkon00/codeforces-darktheme?tab=readme-ov-file#download-instructions
firefox extensions exist.
you can use mirror websites during contest, it has dark mode
I want to use dark mode in night when practicing but today i will use mirror website in todays contest :)
just destroyed my Dark Reader
https://codeforces.me/blog/entry/151147 trust
i came.
i saw.
i left.
hopefully we get a faster queue
please father give us a faster queue amen
Awesome news! As long as CodeForces stays free of paid premium perks like leetcode or codechef, anything works :)
Nice to hear but I didn't know Telegram stopped sponsoring Codeforces
so something changed? cuz i thought telegram was a sponsor before
Nice
Amazing news! Looking forward to what comes next
Guys, maybe, just maybe, this would give Mike a chance to add AI-detection to CF (or report button)
Also deleting random bot accounts which only submission and downvote spams(Like this comment got -12)
yeah yeah yeah it's just somehow annoying when your comment just hits
-1and then bots started streaming negative votes and reducing reputation. cuz of this, reputation is hard to increase unlike ratingcongrats cf team! =)
Good
don't worry mike, i'll sponsor if it comes to it
"Thank you sroshc" we all say in unison
Forgive mine utter foolishness, for in my gross ignorance I took thee for a mere loquacious gapple; yet lo, thou art none other than THE ENCHANTED TALKING GAPPLE of ancient lore!
(prostrateth in lowliest obeisance)
Good news! My tests show that C++ programs with long double works in 3 times slower in comparison with another platforms, and I hope, that the new infrastructure will be able to resolve this problem too.
yeah it's annoying as fuck. got 7 TLEs on a gym problem because of it
nice avatar bro
Congratulations Mike! Big thank you to Pavel.
Nice
genuinely great. excited. the infrastructure upgrade sounds like a huge win for everyone who regularly competes here.
if something could be developed to keep the cheaters at bay in future updates...please. like tab monitoring or a dedicated desktop app maybe?
I think my comment carries a risk, so I'm going to edit it. That is why you will never find out what happened here
" that is why you will never find out what happened here" The humble arrow next to Rev.:
oh, i completely fucked up
Bro thought that this is Youtube :skull:
I thought youd manage to solve problem C in Edu 194 and pull way ahead of me :skull:
bruh I thought that nobody would add friend me
I have you friended lol but I wonder who friends me
What?
i friended you like 6-7 months ago
did you forget that we can see your post before you edited it
Telegram is back, servers are getting upgraded… now we just need to upgrade our ratings.
great)
Great, can telegram also somehow show codeforces in their app?
Telegram is sponsoring Codeforces, not the other way around
oh thanks
this is really awesome news!
Please make the div3,4 more than that its now like one in a tow months :(
Can't agree more! This is really important for those of us who are at a beginner level!
Yes, please, at least div3
high time to take action against Users who cheat in live contest with Ai or other stuffs.
orz PFP!!
that's great to hear.
Pavel Durov orz
MAKE CODEFORCES GREAT AGAIN!
damn!!! it was originally GREAT!
good
Great, It's time for DARK MODE now.
Hi, Durov, PEPE PEPE PEPE PEPE PEPE PEPE PEPE PLEASE PLEASE
respect to Pavel
give me one dark mode please
Stylus extension: CodeForces Zen
This is great news.
GREAT
that's Great
what is this change?
Wow, insteresting.
Nice
Found a useful tool for anyone who practices DSA: WorthSolve — helps you decide which problems are actually worth solving and discover better problems across platforms.
https://worthsolve.bolt.host
Would love some feedback from fellow competitive programmers!
Dm me Email — [email protected]
https://codeforces.me/blog/entry/13417 12 years ago
great news
News straight from the source: https://t.me/durov/548
Now its been a Teleforces
So will the queue be only 15 minutes now?
Awesome
MikeMirzayanov I’m sorry for bringing an account issue into this thread, but I currently don’t have another way to reach you. My original Codeforces account "nisubhai333" has been disabled and shows “User is disabled by administrators.”
I have not violated any Codeforces rules, and I genuinely don’t know what caused the disablement. I’m using this account only because I can’t access my original one.
Could you please take a look at "nisubhai333" and let me know what happened or where I can request a review? I can provide the Gmail associated with the original account to verify ownership.
I would really appreciate your help.
Mike, can you please now take a look at this blog
Nice to see this, I use telegram as my main communication with my friends.
You also used telegam to cheat that way you reached master. Blog with proofs.
Very nice great news
Now maybe ask Telegram to sponsor one more feature, shutting down the channels that provide full solutions during live contests. :)
I think its time for dark mode
Telegram premium as a gift if you reach a new color?
MikeMirzayanov I’m sorry for bringing an account issue into this thread, but I currently don’t have another way to reach you. My original Codeforces account "nisubhai333" has been disabled and shows “User is disabled by administrators.”
I have not violated any Codeforces rules, and I genuinely don’t know what caused the disablement. I’m using this account only because I can’t access my original one.
Could you please take a look at "nisubhai333" and let me know what happened or where I can request a review? I can provide the Gmail associated with the original account to verify ownership.
I would really appreciate your help.
Let's go , W Pavel Durov :)
If so, then please give us at least 8 contests this month.
Codeforces isn't it time to add an anti-cheat system?
This is a comment where i posted somewhere else: Can't Codeforces implement an anti-cheat system similar to Chess.com's? Codeforces can track things like mouse movements, Ctrl+C/Ctrl+V usage, users' contest history, and coding patterns. All Codeforces has done so far, as far as I know, is address a prompt-injection incident in one of its contests. Chess.com tracks things like mouse movements, the time spent on each move, and other behavioral data, so I think Codeforces could implement similar measures as well. I also can't believe we still don't have a report button :/ (BTW i used AI to improve my comment ^-^)
wdym by saying "Ctrl+C/Ctrl+V usage"? I believe that most people code on IDEs, in which Codeforces system can not track. Also, I honestly think that mouse movements can not help much. Nonetheless I think that the two others are okay to develop.
I was just giving some examples. If I already knew how to implement it, why would I be asking Codeforces? /:
Also, by tracking Ctrl+C/Ctrl+V usage, I mean that a lot of users simply copy the problem statement and paste it into an LLM. You could potentially detect that behavior. Of course, it wouldn't be reliable on its own, since they might translate the problem, but it's still behavioral data that could be useful when combined with other signals.
And keep in mind that we can never catch every good cheater. The goal isn't to create a perfect anti-cheat system; it's to catch cheaters who make mistakes and leave traces behind.
And mouse tracking could be useful too. For example, if someone moves their mouse downward toward the taskbar and then switches to another editor or application instead of upward to switch tabs, could be another behavioral signal worth taking into account.
Of course, none of these signals would be reliable on their own, but when combined with other behavioral data, they could help identify suspicious patterns.
some people copy statements to translate
I think i clearly mentioned that in my reply
And BTW guys if you just have any other ideas say it, these are just my idea from chess.com's anti-cheat system :D
Maybe make problem statement as image and disallow printscreen if its possible. into authentication code apps you cannot make a screen using mobile phone. the same needed here.
where can i report cheaters?
u cant report cheaters., but yea u can make blog on them
how will i make sure that it has reached to the administrators?
u cant make sure., but maybe mike will see it if u post it on blog
chances r huge that it will go unseen
We didn't get actually, what the difference between sponsored by TON and Telegram? I thought it's something like sponsored by Google and Alphabet thingy
Doesn't have the same ring to it
Cool
Its awsome and nice.
@MikeMirzayanov
I'm sorry for bringing an account issue into this thread, but I currently don't have another way to contact you.
My original Codeforces account @Kalimuthu has been disabled and I cannot access it. When I try to log in, it shows:
“User is disabled by administrators.”
I have also tried password recovery and Google login, but the account remains disabled.
Could you please take a look at @Kalimuthu and let me know the reason for the disablement or where I can request a review?
I can provide the registered email and any other information required to verify ownership.
Thank you for your help.
áu áu
can we make the "remember me for a month" option last forever instead of a month already
For real bro ):
Great :D for the community.
Please fix queueforces (which is happening right now)
Well, Great i guess, good.
Maybe make problem statement as image and disallow printscreen if its possible. into authentication code apps you cannot make a screen using mobile phone. the same needed here.
W telegram
Hello @MikeMirzayanov, My Codeforces account @rahul.kumarundergrade has been disabled by administrators, and I am unable to log in.
I would respectfully like to request a manual review of my account and recent contest submissions. I would also appreciate clarification regarding the specific reason for the disablement and whether there is any particular submission or rule that I need to address.
If possible, please let me know how I can proceed with an appeal or account review.
Thank you for your time.
hello!!!!!!
Great to see this
That's great to hear! I do love this website <3
Well Good
Rating my code pls.
~~~~~~~~~~~~~~~~~~ //this is code
include<bits/stdc++.h>
using namespace std; const int maxn=200005; long long n,a[maxn],w[maxn],node[4*maxn]; void update(long long id,long long l,long long r,long long pos,long long val) { if(l==r) { node[id]=max(node[id],val); return; } long long mid=l+(r-l)/2; if(pos<=mid)update(2*id,l,mid,pos,val); else update(2*id+1,mid+1,r,pos,val); node[id]=max(node[id*2],node[id*2+1]); } long long query(long long id,long long l,long long r,long long u,long long v) { if(v<l || u>r || u>v)return 0; if(u<=l && r<=v)return node[id]; long long mid=(l+r)/2; return max(query(2*id,l,mid,u,v),query(2*id,mid+1,r,u,v)); } int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); freopen("SEGMENTWLIS.INP","r",stdin); freopen("SEGMENTWLIS.OUT","w",stdout); cin>>n; vectorvals; for(int i=1;i<=n;i++) { cin>>a[i]; vals.push_back(a[i]); } for(int i=1;i<=n;i++)cin>>w[i]; sort(vals.begin(),vals.end()); vals.erase(unique(vals.begin(),vals.end()),vals.end()); for(int i=1;i<=n;i++)a[i]=lower_bound(vals.begin(),vals.end(),a[i])-vals.begin()+1; long long m=vals.size(),kq=0; for(int i=1;i<=n;i++) { long long mpw=query(1,1,m,1,a[i]-1); long long ht=mpw+w[i]; kq=max(kq,ht); update(1,1,m,a[i],ht); } cout<<kq; return 0; } ~~~~~~~~~~~~~~~~~~~~~~~~~~ ILY
vote for unrated
Telegram hire me plz i want to fix my hireline like Pavel Durov
we just wain for colab with @nvdia :>
Рад за кодфорсы)
Now that you have improved servers, would it be possible to consider adding more support for CAPTCHA instead? The current CAPTCHA can be quite frustrating. I sometimes have trouble passing it even though I’m a real-world user.
where can i report cheaters?
Hello MikeMirzayanov Sorry for posting an unrelated account issue here. My Codeforces account 0mar_1 has been disabled and shows “User is disabled by administrators.” I cannot log in to my account, and I have not received any email explaining the reason. I am contacting you through my friend's account because I cannot create a blog post from my disabled account. Could you please tell me how I can request a review or contact the administration regarding my account? I would really appreciate your help. Thank you.
Hi, my submissions have been stuck in “In queue” for 7+ hours (since Oct 18, 10:55 IST), while other users’ submissions are being judged normally. Handle: JacobianJedi. Affected submission IDs: 395068678, 395071101, 395071763, 395074530, 395082272, 395094443. Language: C++17 (GCC 7-32). Could you please check or rejudge them? Thank you.