Hello everyone!

I am glad to announce that soon will Codeforces Round #303 for Div.2 paricipants, the author of which I am. Traditionally Div.1 participants can take part out of the competition.

This is my first round, and I hope that it will be interesting.

Round wouldn't take place without the help of the Codeforces team! Great thanks to Zlobober for helping me preparing the round and Delinur for translation. Special thanks to everyone who puts his effort into the creation and maintenance of Codeforces and Polygon systems.

Score distribution will be announce later.

Good luck and inspiration!

UPD Score distribution will be — 500-1000-1750-1750-2500.

UPD Congratulations for winners in Div.2:

1. Bell-sama
2. anko
3. BobDylan
4. Gusheng
5. Diguised
6. imyyimdog

And in Div.1:

1. ngfam_kongu
2. Laakeri
3. Um_nik
4. KrK

UPD Link for editorial.

Hi everybody from the ICPC Live team (elizarov, pashka, niyaznigmatul, Egor, lperovskaya and me).

We want to inform you, that broadcast of the World Finals will take place on Wednesday, 20th of May.

The broadcast will be on the two websites (youtube and twitch). The links will be posted tomorrow, but you could subscribe to our channel.

We will have the following schedule:

• 12:00 — broadcast starts
• 13:00-18:00 — contest
• 19:00 — closing ceremony

Don't forget to subscribe on our channels on youtube and on twitch: icpclive1 and icpclive2.

While you wait, on Tuesday, May 19 Dress rehearsal will take place. The broadcast will be available on the youtube channel ICPC Live and on the twitch channel ICPC Live. The idea of this broadcast is to check, if everything is fine, so, please, be nice and report availability or performance issues. We can't guarantee the good broadcast.

Regards, Team ICPC Live

UPD: Read live ICPC Finals text broadcast. http://icpcnews.tumblr.com/post/119424970944/world-finals-live

UPD2: youtube

UPD3: twitch, main screen, twitch, split screen

UPD4: Thanks to alexyz for the link: multitwitch

The last but not the least interesting team is ITMO University's team 1.

ITMO has most championship titles, 5, out of 19 finals they participated in. They've got 10 Gold medals total, 1 Silver and 1 Bronze.

This year team consist of 2 Bronze Medalist from 2014, Borys and Artem, and World Champion from 2013, Gennady. Team is on first place in OpenCup Standings, won numerous contest this year and universally regarded as favorite to win World Finals, are coached by Andrey Stankevich.

Gennady Korotkevich (TC: 3794, CF: 3407) is one of the most honored coders ever. ACM ICPC Champion in 2013, TCO Winner in 2014, GCJ Winner in 2014, IOI Gold Medalist for a whooping 6 years (2007-2012), that's in addition to SIlver (2006) and many more achievements like Facebook Hacker Cup wins.

Borys Minaiev (TC: 2760, CF: 2776) won Bronze in last year Finals, was TopCoder Open Semifinalist in 2014, Facebook Hacker Cup Finalsit in 2015 and got 3rd place in Kotlin Challenge in 2014.

Artem Vasilyev (TC: 2612, CF: 2545) got World Finals Bronze in 2014 and was KROK Finalist in 2013.

It would be really unlikely for ITMO not to win Gold Medals, I have their chances at 99%. I think their chances to win is about 75%.

Create your own ICPC cheering party, join one in you city or just follow ACM ICPC World Finals Live

This year my alma mater is represented by team Moscow SU Tapirs.

Moscow State University has a long history at World Finals. 19 appearences, 4 Gold medals (all of them — 2nd places), 1 Silver and 7 Bronzes. Moscow SU is also 2 times champions of Europe.

Tapirs team came 2nd last year in Yekaterinburg in intense battle with St. Petersburg State University. In NEERC 2014 they came second as well, while losing to ITMO University team only on penalty time. Moscow SU is currently 3rd in OpenCup standings with one stage win. They had bested ITMO team on 2 more stages. Anton Pankratiev is team coach.

Gleb Evstropov (TC: 2405, CF: GlebsHP 2622) got 3rd in this year Facebook Hacker Cup. He also won Silver medal in IOI 2010 and was Russian Code Cup finalist last year.

Victor Omelyanenko (TC: 2531, CF: TeaPot 2687) got 2nd place on ACM ICPC World Finals last year with Gleb and Mikhail.

Mikhail Pyaderkin (TC: 2428, CF: meshanya 2550) won IOI Gold in 2010 as well as placed 2nd in Vekua Cup personal contest in 2012.

This team got only stronger since last year. Their chance to win Gold are at least 80%, while they had shoy at Championship as well, with about 15% chance.

Last team to look at will be ITMO University team.

Create your own ICPC cheering party, join one in you city or just follow ACM ICPC World Finals Live

Today let’s talk about The University of Tokyo team !#$%&()*+-./:;<=>?@[]^_`{|}~. University of Tokyo has long history of World Finals participations, this would be 13th time. They won one Gold, one Silver and 2 Bronzes, and 2 members of this year team won Gold in 2013.

They won regional contests in Tokyo and Kuala Lumpur, only team in Asia this year with such achievement. Team is currently on 17th place in OpenCup standings, although they skipped several stages and not always had optimal line-up. Tomoyuki Kaneko coaching them.

Kensuke Imanishi (TC: 2625, CF: wrong 2298) won 2 Silver medals in IOI (2010 and 2011) and was GCJ Finalist in 2013, that's beside his Gold in ACM ICPC Finals.

Shogo Murai (TC: 3017, CF: semiexp 2507) has 3 IOI Golds (2010-2012) and target on TopCoder to boot.

Makoto Soejima (TC: 3468, CF: rng_58 2849) is really a legend. He is one of only 4 people to win both GCJ (2011) and TCO (2010, 2011) and currently is TopCoder admin. Beside that he has Silver in IOI (2008, 2009) and Gold in World Finals.

While this team has really strong line up it's results are inconsistent. I'd give them 70% for Gold and about 5% to win.

Tomorrow we will look at team from my alma mater, Moscow State University.

Create your own ICPC cheering party, join one in you city or just follow ACM ICPC World Finals Live

Second team to look at is University of Zagreb

Once again, this third appearance of Zagreb’s team at World Finals and both in 2008 and last year teams got Silver medals. Stjepan Glavina and Ivan Katanic both participated in 2014 Finals.

Team decisively won CERC 2014 with 10 solved problems to second place’s 8. They participated in 3 stages of OpenCup, not very successfully though, and with 15 points are currently in 73rd place. Team also finished 5th in elimination round of Deadline 24. Zagreb’s coach is Kresimir Malnar.

Stjepan Glavina (TC: 2620, CF: 2509) won Gold in IOI 2009 and Silver in 2010.

Ivan Katanic (TC: 2704, CF: 2613) also has 2 IOI medals — Gold in 2011 and Silver in 2010.

Gustav Matula (TC: 2179, CF: 2160) had got his IOI Gold in 2011.

This team as about on par with Lviv, so I predict about 60% chance to get Gold medals and 1% for win.

Check back tomorrow as we’d look at University of Tokyo team.

Create your own ICPC cheering party, join one in you city or just follow ACM ICPC World Finals Live

Hello, this is Egor. Today we are starting previewing some teams from ACM ICPC World Finals in Marrakech that, by my opinion, have most chances to win gold medals. First to go is Lviv National University team LNU Penguins.

Some trivia: Lviv NU participated just 2 times, but got gold one of those times, in 2008. One of participants of that team, Vasyl Biletsky, is current team's coach (but we should note that he actually was his own team's coach in 2008 as well).

This year team qualified to World Finals as winners of SEERC. They are currently 11th in OpenCup standings (do note, however, that there are many teams in that standing that are not ICPC eligible for one reason or another).

Roman Bilyi (TC: 2513, CF: 2672) participated in Russian Code Cup Finals in 2014 and won Bronze in Snarknews Winter Series 2015

Vitaliy Herasymiv (TC: 2206, CF: 2356) won Silver in IOI 2012

Bohdan Pryshchenko (TC: 2269, CF: 2348) won Gold in Snarknews Winter Series this year and Silver in Summer Series last year.

I believe this team has decent chance to clench gold, about 60%, while their chances to win are slim, about 1% or so.

Stay tuned for tomorrow as we will look at our next team from University of Zagreb!

Create your own ICPC cheering party, join one in you city or just follow ACM ICPC World Finals Live

So few minutes ago I answered this question on Quora. It felt like a good answer (because it has pictures), so I would like to share it again here.

If you don't see the images, just click the Quora link above

Many people tell you that solving lots of problems and you will become red on Topcoder/Codeforces one day. It is true, and is the only universally approved way in competitive programming community, but actually it is just half of the story. Let me first explain to you the 'science' of problem solving (which is not very scientific, since it was only developed by myself).

For each problem, in order to solve it, you must jump over a gap. It can be either a difficult implementation, or some hard-to-see observation, or difficult algorithm, etc.

For me, some problems are very easy (e.g. Codeforces div 2 A, B..), because the gap feel so small to me, and passing through them feels just like casual walking.

Some problems are very hard. The gap is just too huge, or there are many many gaps, and you can get stuck in the middle because you're too tired after maybe first gap.

Using this science, we can explain a lot of phenomenon in the competitive programming world:

• Some guys learn very fast, got to div 1 only after like a couple of weeks after he just started programming: Some people are born with high jumping ability (problem solving skill). They can jump over average gaps easily.
• The more you train, the better you become: Of course, if you jump around all day, you must be somewhat better at jumping through gaps, and thus being able to solve more difficult problems in less time, since you don't need lots of mental preparation or warm up excercise before jumping.

But.. it also means that, if you just solve too easy problems, you can still only walk through small gaps. You may walk through gaps faster, but you are still unable to jump.

So yes, the best strategy to improve your competitive programming skill is to practice a lot, but you must solve gradually harder problems, not just the easy ones. Get out of your comfortable zone and challenge yourself. For example, if you solve problems on Codeforces:

• Sort by number of people who solved it.
• Start with page 1
• Solve some problems. If you feel you can solve them in like 5-10 mins, immediately ignore the other problems, move on to page 2
• Continue until you feel challenged (e.g. need like an hour to solve / can not solve at all / ...).
• Try really hard, but if you fail, look at editorial, ask for solutions, ...

Participating in a big competition like IOI or ICPC can be intimidating, the worst thing that might happen to you is that you manage to get nervous enough to enter that adrenaline-fueled fight or flight state, you start feeling that you need to get out of the contest fast. An easy bruteforce solution that would take you 2 minutes to code in a normal environment suddenly requires 10 minutes, or at least that's what happened to me the last 3 major competitions I participated in (APIO 2014, IOI 2014 and APIO 2015), while it wasn't very noticeable in APIO 2014 -I quickly forgot about it because it was my first medal a bronze one- and I blamed that state on sickness in IOI 2014, after APIO 2015 it became clear to me that I'm making the mistakes over and over.

If you're really new to competitive programming, someone who doesn't really care much about the result, or someone who's trained since the age of 6 you probably won't relate to these issues, but after I've done some research I realized that this is more common than I expected. The same pattern happened to me every time: I had the right ideas, I got WA on my first submission, I panicked and then my brain basically stopped working (and of course all the known symptoms of the fight or flight state).

I remember talking to someone after day 2 in IOI 2014, he told me: "When I read the problems, my brain stopped working I didn't even understand them, after the contest I read them again and came up with 243 points worth solutions". And his solutions were very neat and differ to the tutorials that were given to us after the contest.

So the point that I'm trying to make is: If I and everybody who suffers from the same problem, could solve problems during a competition as big as IOI with the same level of problem solving skill we usually demonstrate in any other environment, our results would differ greatly.

Have you ever had those issues? Did you manage to fix them?

Also in case of IOI-like competitions, what is your general strategy?

UPD: I got a bronze medal in IOI, the advice bellow is really helpful

It is really great to spend holyday usefully. During the Victory Day I not only visited the Victory Park with family, congratulated people closed to me, watch the Victory Day Salute, but also I've started to get rid from codeforces.ru

Yes, it is not a mistake. We are moving forward to use the only domain codeforces.com. It will make many thing better: better navigation, better page statistics, better pagerank and other metrics.

Of course, all links to codeforces.ru is redirecting to the appropriate page on codeforces.com now. In addition, for now it applies only to GET-requests.

Observant visitors have noticed that recently changed how we deal with images. Now, if you insert a link to image into the text of a post/comment, then when you save it predownloaded and stored on Codeforces, and link is replaced by to use our domain. This solves several problems: missing or spoofed pictures in old posts/comments, the restriction on the number of views in original image server, we resize too large images to smaller size, now we be sure to use https for images, which means we are closer to use https.