Joshc's blog

By Joshc, history, 5 months ago, In English

Hello Codeforces!

Yet another time, this is yet another message in yet another blog post, with yet another announcement regarding yet another invitation to yet another Yet Another Contest! Yet Another Contest 8 will be hosted by DMOJ from Friday, February 2 00:00 EST to Friday, February 9 00:00 EST. Participants will be given a 3-hour window to solve 6 problems with varying difficulty, with the difficulty being between Div. 1 and Div. 2 levels. This contest will be rated for all users with ratings less than 3000.

We hope to see you compete! Good luck and have fun!

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By Joshc, 10 months ago, In English

Hello Codeforces!

Yet another time, this is yet another blog post, with yet another announcement regarding yet another invitation to yet another Yet Another Contest! Yet Another Contest 7 will be hosted by DMOJ from Friday, August 11 00:00 EDT to Friday, August 18 00:00 EDT. Participants will be given a 3-hour window to solve 6 problems with varying difficulty, with the difficulty being very slightly harder than Div. 2 level. Unlike the previous YAC, this contest will be rated for all users with ratings less than 3000.

We hope to see you compete! Good luck and have fun!

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By Joshc, history, 11 months ago, In English

I've somehow managed to get 3rd place in the Div3, a new career high!!! If I had done F and G in the correct order, I would've saved 19 penalty, rip (although my rank wouldn't have improved).

Anyway, to celebrate, I've posted my screencast / explanations here. Hopefully people enjoy!

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By Joshc, 14 months ago, In English

Hello Codeforces!

I've decided to make a series of videos about SQRT algorithms, with the first being about bucketing! Hopefully, there is a non-trivial application of bucketing in this video which you might find interesting. It's available here.

I'd really appreciate feedback / suggested topics for future videos!

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By Joshc, 15 months ago, In English

Hello Codeforces!

I've decided to try doing something new with my youtube channel... start making tutorial videos! The first tutorial video is on offline algorithms and the sweepline: check out the following link to learn about the concept of offline algorithms, and two different visualisations to understand sweepline-based techniques.

Feel free to give any feedback or request topics for future videos!

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By Joshc, 18 months ago, In English

Hello Codeforces!

Yet another time, this is yet another blog post, with yet another announcement regarding yet another invitation to Yet Another Contest 6, which will be hosted by DMOJ from Friday, December 23 00:00 EST to Tuesday, December 27 00:00 EST. Participants will be given a 3-hour window to solve 6 problems with varying difficulty, with the difficulty being approximately Div. 2 level. Unlike the previous YAC, this contest will be rated for all users with ratings less than 2800.

Also, this contest has prizes, for both rated and unrated users, one of which is randomly selected. These prizes include Discord Nitro and steam codes for Sid Meier’s Civilization VI. See the contest page for more details.

We hope to see you compete! Good luck and have fun!

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By Joshc, 20 months ago, In English

Hello Codeforces!

Yet another time, this is yet another blog post, with yet another invitation to Yet Another Contest 5, which will be hosted by DMOJ from Friday, October 21 00:00 EDT to Tuesday, October 25 00:00 EDT. Participants will be given a 3-hour window to solve 5 problems with varying difficulty, with the difficulty being approximately Div. 2 level. Unlike the previous YAC, this contest will be rated for all users with ratings less than 2600.

We hope to see you compete! Good luck and have fun!

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By Joshc, 23 months ago, In English

Hello Codeforces!

This is yet another blog post, with yet another invitation to Yet Another Contest 4, which will be hosted by DMOJ from Friday, August 5 00:00 EDT to Tuesday, August 9 00:00 EDT. Participants will be given a 3-hour window to solve 6 problems with varying difficulty, with the difficulty being approximately Div. 2 level. Unlike previous YACs, this contest will be rated for all users with ratings less than 2800.

We hope to see you compete! Good luck and have fun!

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By Joshc, 2 years ago, In English

Hello Codeforces!

This is yet another invitation to Yet Another Contest 3, which will be hosted by DMOJ from Friday, May 27 00:00 EDT to Tuesday, May 31 00:00 EDT. Participants will be given a 3-hour window to solve 5 problems with varying difficulty, with the difficulty being approximately Div. 2 level. Note that only users with a rating under 2600 will be rated.

We hope to see you compete! Good luck and have fun!

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By Joshc, 2 years ago, In English

Hello Codeforces!

From Friday, April 1 00:00 EDT to Tuesday, April 5 00:00 EDT, DMOJ will be hosting Yet Another Contest 2 (and no, it's not a terrible April Fools joke). Participants will be given a 3-hour window to solve 6 problems with varying difficulty, with the difficulty being approximately Div. 2 level. Note that only users with a rating under 2600 will be rated.

We hope to see you compete! Good luck and have fun!

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By Joshc, history, 2 years ago, In English

Hello codeforces!

Too often, I find editorials with only the solutions to the problems, without any explanation as to how one is to derive them. Whilst I appreciate that there are infinite intuitions and derivations leading to any solution, I thought it would be good if I shared my own intuition, so hopefully people can learn and apply similar ideas and techniques for future problems!

I've made a video editorial explaining my intuition at https://youtu.be/3X-1PBLepwY for anyone who is interested, as well as my 35th place commentated screencast at https://youtu.be/q_RPqdRjmuM ! If there is enough demand, I'll also write my intuition in this blog.

Wish you all good luck in the future!

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