codemastercpp's blog

Reconstructing Old A2oj Ladders with new problems
By codemastercpp, history, 3 years ago, In English

Hello CF,

UPD:

Sorry for necropost(?), but I had a lot of DMs about website being down, so I've updated it.

But the old link is invalid now, and it is hosted at: https://c2-ladders-juol.onrender.com

Thnx

I've seen a lot of people say very good things about a2oj ladders but I never used it because the problems in it are very old, as it was constructed by ahmed_aly 4-5 years ago, so I decided to try to recreate the ladders with updated data of codeforces, especially because nowadays CF is quite ad-hoc (and I like it:D).

I mostly followed the same procedure as described here, with some little changes, one of them being not having 800 rated problem in 1500 ladders, these ladders are based on problem rating. You can visit the website here https://c2-ladders.com

If you want to learn more about how I did it, I've uploaded a video on how I constructed it, which you can see here: https://youtu.be/xQuNwSFi4Ag

The website and the script both are open sources, feel free to make a PR if you want some change or just tell me in comments.

Website: https://github.com/prince776/c2ladders

Script: https://github.com/prince776/scripts-yt/tree/master/ladder

Here's a preview

Why C2Ladders? Well it stands for codemastercpp's codeforces ladders.

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Comments Comments (30)
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3 years ago, # |
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Auto comment: topic has been updated by codemastercpp (previous revision, new revision, compare).

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3 years ago, # |
  Vote: I like it +10 Vote: I do not like it

Also the script took 20hrs to finish if anyone wanna run it again :D

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3 years ago, # |
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I love it, thanks for the contribution.

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3 years ago, # |
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Hey CMC, This ladder is so damn helpful A suggestion would be to please add the facility to add the CF username to keep a track of all the problems solved so far from the list

CMC orz!

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    3 years ago, # ^ |
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    search your username on the search bar, it'll show which problems you've as AC/WA/TLE/MLE/RE/Others

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3 years ago, # |
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Small suggestion: I noticed that all of the problems in "< x" ladder are of rating "x — 100", so maybe just rename them to "x — 100" instead?

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    3 years ago, # ^ |
    ← Rev. 2   Vote: I like it +19 Vote: I do not like it

    so Like name ladder like

    800, 900, 1000, 1100, ... ?

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      3 years ago, # ^ |
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      like 900-1000,1000-1100 i guess thats what he meant just like a2oj did , looked nice

      Also if you would add a small number showing over the tab that how many had i solved and make a slide green line like a2oj which increases as you solve questions from that section

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        3 years ago, # ^ |
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        oh ok, but shouldn't it be like 1200-1299, since 1300 is not included?

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        3 years ago, # ^ |
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        He probably meant what he has written, write 800, 900, 1000, ..., 3400, and 3500 instead of <900, <1000, <1100, ..., <3500, and <3600.

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3 years ago, # |
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Hey, I would suggest add tag option too in the website

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3 years ago, # |
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Thanks for reconstructing , one request please add topic wise too sorted in difficulty order.

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3 years ago, # |
  Vote: I like it +8 Vote: I do not like it

Thank you for reconstructing the ladders.

The ladder also has a minor issue: it includes the same problem twice. For example, the problem Dreamoon Likes Coloring appears twice in the 1800 ladder.

Many contests can separate divisions. Usually, different divisions can share some common problems, i.e., Div.1 A can be similar to Div.2 C. My suggestion is to come up with some unique identifier for a problem. The identifier could be a pair of (name, rating).

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    3 years ago, # ^ |
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    Actually there are different problems with same name, rating, I've deployed some changes to filter out based on name, contestId where contestId checks adjacent contests.

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3 years ago, # |
← Rev. 2   Vote: I like it +1 Vote: I do not like it

cmc how so orz?? any tips Also change the svg icon of website :)

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3 years ago, # |
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Great work!!

I have a request. Would it be possible to have the username search persist after reloads?

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3 years ago, # |
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What does the term frequency means? I don't think that's the submisson count right?

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    3 years ago, # ^ |
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    Ig it only counts for users whose rating increases by at least 150 within 6 months time frame after solving that particular problem.

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3 years ago, # |
  Vote: I like it +18 Vote: I do not like it

Hi, just a suggestion, can you make it so the webpage opens to a unique link when you enter you username and/or are in a particular difficulty section, how i open your site is through bookmarks on my browser and i have to navigate the site a bit each time to get to my settings ( i.e. inputting handle and selecting difficulty) if the url became something like https://c2-ladders.com/users/amarnathsama?difficulty=1800 then it would open at once, like this on Codeforces 1800 difficulty problems.

Also, really awesome site, this is my go to site now for practicing!

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3 years ago, # |
← Rev. 2   Vote: I like it +9 Vote: I do not like it

I found bug(it has some problems in the list,but i show only for one): So click 1000: We have two fair numbers problems(58 and 99 in section now): https://mirror.codeforces.com/contest/1465/problem/B https://mirror.codeforces.com/problemset/problem/1411/B it is the same problem,only different name of contest So it is possible that we have 2 the same names and one is solve and one not)one is green,second not

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3 years ago, # |
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What's the meaning of frequency in your list?

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    2 years ago, # ^ |
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    I guess, it means how many correct submissions for this problem have been recorded during the contest.

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2 years ago, # |
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Well done

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15 months ago, # |
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The website is down for 3 days. Can anybody say why?? (09/27/2023)

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

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7 months ago, # |
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Hey man I would request you to update the list with newer problems too coz it's been two years. Would mean a lot if you consider it.

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7 months ago, # |
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Why doesnt the site work for me?

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