Hello Codeforces!

I decided to finally do a screencast and a full editorial, hope you'll enjoy watching.

Screencast

Video Editorials

Discord Server

Hello!

Since the editorials are still not out, I prepared video editorials for div2 B, C and D.

B

C

D

Check the videos and if you liked them, subscribe to the channel for more CP content

Hi!

While I was solving some National Olympiad problems, I came up with an interesting DSU trick which can be used instead of Parallel Binary Search.

Now that I started an YouTube channel, I decided to make a video based on it.

If you enjoyed watching, please leave a like and press the subscribe button.

Also, if you know the name of this trick, please share it here or on Youtube comment section.

Hello!

I just uploaded a video about my opinion when it comes to approaching Codeforces contests.

Here

Everything I said is just the result of my personal experience with doing contests and I hope you liked my content.

You can also join my new discord server where I will interact with the subscribers and also with those interested in algorithmics.

Here

Hi guys, I hope you're all staying home safe from COVID-19.

I decided to start an youtube channel where I'm going to explain various problems, both in English and in Romanian.

The latest video, where I'm trying to solve a div1B from a recent Codeforces Round

Even though I'm just a beginner when it comes to doing such content, I will definitely improve as time goes by.

You can leave suggestions in comments and subscribe to the channel, if you enjoy the content.

I hope you'll enjoy watching those tutorials.

The registration for the next Div3 is restricted to people with rating lower than 1600, and this shouldn't be the case, since Div3 contests allow out of contest participation.

It seems like uphacking is affecting rating changes, this shouldn't happen.

rip fishy

some other people too

Hi, Codeforces!

I've observed that in the last several months, I haven't managed to achieve a significant progress in average rating on CF and i started to worry whether I touched my peak potential or not, so I came here to ask you some questions. I know it's a debated subject, yet I still think it's sensible to talk about this, so I came up with some questions I still haven't found a clear answer to.

1) When do you believe one has touched his/her peak(bonus points if you're talking about yourself)?

2) If you ever believed you're stagnating, how did you change your way of practice and why?

3) Do you think that everyone has its maximal potential? No matter what do you believe, I'd like to see you state the reasons why you believe/don't believe everyone has a maximal potential.

If you have tips to counter this problem, please share them here, they will help me and many other people now and in the future.

Hi everyone!

ICPC World Finals 2019 are approaching and we're proud to announce that we're going to be a discussion place for all those who have qualified to the World Finals.

If you are one of the finalists, you can join our server to take part in the special ICPC World Finals chat.

Good luck and have fun!

Codeforces's virtual contests are probably one of the best feature in CP, since it allows people who can't do the contests because of various reasons to have a chance to simulate the contest. However, the virtual contest format doesn't consider the fact that the real contestants had pretests and system tests, while in a virtual contest, the source gets evaluated to all the tests in the moment of submission.

So, I suggest that the virtual contestant should be able to choose whether he wants to get his solution tested only on pretests(just like in the real contest) or to have full feedback(the current format of VC as of now). I don't think this isn't that hard to implement, CF can probably still evaluate all the tests and show "Pretests passed" if the source passed a certain test number(the number of pretests which this contest had).

I think this is a problem which concerns most of the people who are using the virtual contest feature, so fixing this problem would improve this feature significantly.

MikeMirzayanov KAN What do you think about this? Can it realistically be implemented in CF?

Ever since tzuyu_chou started advertising Twice at round #497, an increasing number of people have got to hear about this band, and it seems that for most of them, it was a great deal in their competing skills.

Even though at first I was reluctant about how can a K-pop band, especially Twice can improve people's CP skils, but after seeing that many guys with K-pop related accounts performing great made me start listening to Twice too and soon after this, I managed to get Master for the first time ever, after struggling in purple for a long time.

The examples can continue, so is listening to Twice really boosting cp skills?

I'd like to hear other successful stories too, so that i can be sure that my skill gain is not just a result of hard work.

Hello Codeforces!

As i randomly observed by reading an editorial blog, when i searched for contests done by same author, there was shown a contest which seems to have no link to that user

The author shown

Announcement blog, totally unrelated

Editorial blog, totally unrelated

However, div1 version is correctly attributed to the actual author

As you can see, author's name and the actual writers have no link to each other, unless i missed something which is not shown in any of the announcement or editorial. Will this be fixed?

Hello Codeforces!

I've been a member of this community for about 1 year and i'm very glad of how things go there, with a single exception: Educational Rounds.

Ever since they became rated for div2 users, despite of their rather interesting format, they've proved to be a trap for many users, because of hacking period and contest format(extended ICPC). Basically, as a result, in 99% of situations, problem A, which is supposed to be the easiest one, becomes the most important problem, and this is not exactly good, because in many situations, people who have, let's say ABCD and a rather good penalty, end up getting only BCD but with a bad penalty for 3 problems, just because of a single mere error, while in any other contest they would only have gotten a small drop in standings.

Thus, my humble suggestion is to rethink a bit how Educational Rounds(and any ICPC style contest in CF with sorted difficulty problems, like div3 rounds) are working.

One of my ideas is to add weight to each problem, so instead of each problem having the same value (another point on number of problem solved), we can have something like A = 1, B = 2, C = 3 and so on, thus while still advantaging people who did ABCD, it will not hurt people who did something like BCD so much anymore.

Another idea i have thought at is while keeping the current system(people ranked by number of problem solved and penalty), we can add another criteria of separating people's ratings.

For example, a person who solves ABCDE should be better than a person who solves even DEFG, but a person who solves ABCD shouldn't be better than a person who solves, let's say, ABCE

What do you think of those ideas? Can they actually be an useful change for educational rounds and how does it work? Suggest any other ideas in comments and feel free to share your feedback.