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stefdasca's blog

By stefdasca, history, 11 months ago, In English

Hello everybody!

This year I decided to be way more active as far as posting educational content goes so I decided to start with posting video tutorials for as many problems from the CSES problem set as possible, as there are many videos out there which often explain solutions by going through way more details than needed or simply make understanding the problem way more complicated than needed.

Here is a playlist with the solutions I did so far, with the most recent addition being Tree Distances I, a problem I reviewed today in this video.

In order to know what should I focus on going forward in terms of educational content, I would love and be grateful to hear in the comments about topics or problems from CSES or from other places (I prefer more well known/educational ones however) you think they're worth reviewing. I will try to do 2-3 videos a week with the most upvoted comments and I will keep the blog updated as I keep posting solution videos over time.

Here's to a great 2024 and if you find my tutorials interesting and worth watching, you can subscribe to my channel for more content in the future.

UPD: I just uploaded a video solution to Polynomial Queries from CSES. Thank you maxrgby for your suggestion!

UPD2 new video: I just uploaded a video solution to Multiplication Table from CSES.

If you want to suggest more videos, be ready to do it in comments, I want to upload as many solutions as possible. In addition, any feedback is much appreciated as well.

Here is a playlist where you can watch all solutions I posted so far.

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11 months ago, # |
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ok, but genshin impact....

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11 months ago, # |
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thanks for your contribution

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    11 months ago, # ^ |
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    Are there any particular problems you would like me to cover?

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      11 months ago, # ^ |
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      well i always wished if some master in cp did a series of educational videos to guide students doing olympiad, as for cses i think we need editorials for additional problems they are the only ones which don't have any editorials, thanks again community needs people like you.

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        11 months ago, # ^ |
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        Both are good ideas! Actually I started out with Olympiads too and although things have greatly improved compared to where they were 10 years ago when I first learned about programming, there are still a lot of things that are missing.

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          11 months ago, # ^ |
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          yeah i suggest if you can do some kind of roadmap or a serie starting from language level where you suggest problems and do editorials for them along with suggesting topics that would be very good for olympiad people

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      11 months ago, # ^ |
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      It would be great if you could cover range query problems. Thanks a lot for the contribution.

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        11 months ago, # ^ |
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        Sounds good! I actually started working on some of these problems during the winter break so I will probably approach them more too

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      11 months ago, # ^ |
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      There are many problems which gives TLE even on NlogN program probably because of constant factors involved. Can you please make something about that ? Here is one such submission that I did but not getting how to optimize it ? Thanks https://cses.fi/paste/d6230eec95a19a0e7b032b/

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        11 months ago, # ^ |
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        For what problem is this one? I will take the data structures one by one to make them easier to understand.

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          11 months ago, # ^ |
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          That is one such that I faced. may be some implementation problem by me. I tried compressing the salaries and then forming segment tree to answer queries.

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      11 months ago, # ^ |
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      Can I request Polynomial Queries?

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        11 months ago, # ^ |
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        Another good one, I recently solved it and I think it would make for a good start in terms of data structures problems.

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11 months ago, # |
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hello! thank you for tutorials and sorry for offtop can you briefly predict my rating :)

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    11 months ago, # ^ |
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    It's funny that whenever stefdasca posts a blog or writes a random comment there is always someone who asks him "can you pls predict my rating??!!1!?"

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      11 months ago, # ^ |
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      It's been a recurring theme for the last 3 years lol

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11 months ago, # |
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can you please solve "Counting Towers" from the dp section?

UPD: sorry, you already did it. my bad.

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    11 months ago, # ^ |
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    No worries, do you have other suggestions?

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      11 months ago, # ^ |
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      anything from the additional section would be helpful

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11 months ago, # |
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Nobody made any sort of editorials for the "Additional Problems" section of thr CSES problem set. It would be of great help if you did so.

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11 months ago, # |
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Auto comment: topic has been updated by stefdasca (previous revision, new revision, compare).

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11 months ago, # |
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In addition, from next video on, if I choose your suggestion, I will shout your handle, take the opportunity while you can.

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Do you think I will exceed specialist rank on codeforces? I know FFT

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11 months ago, # |
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You could maybe try to post some videos of problems from Additional/Advanced. Most other sections have reasonable tutorials or blogs covering them. Pretty sure no solution explanation exists for a lot of the additional problems.

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    11 months ago, # ^ |
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    I can do that, though a lot of the easier problems also have poor tutorials as well

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    11 months ago, # ^ |
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    Great suggestion, I will try to do it too soon

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Do you think FFT is the right thing for me to learn next? If not, please suggest something diffrent.