codemastercpp's blog

Reconstructing Old A2oj Ladders with new problems
By codemastercpp, history, 22 months 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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22 months ago, # |
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Auto comment: topic has been updated by codemastercpp (previous revision, new revision, compare).

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22 months ago, # |
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Also the script took 20hrs to finish if anyone wanna run it again :D

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22 months ago, # |
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I love it, thanks for the contribution.

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22 months 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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    22 months 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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22 months 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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    22 months 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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      22 months 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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        22 months ago, # ^ |
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        oh ok, but shouldn't it be like 1200-1299, since 1300 is not included?

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        22 months 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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22 months ago, # |
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Hey, I would suggest add tag option too in the website

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

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22 months 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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    22 months 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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22 months 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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22 months 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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22 months 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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    22 months 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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22 months 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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21 month(s) 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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16 months ago, # |
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Well done

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6 months ago, # |
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Great Work.... it lasted long and helped many

but nowadays (recent contest are harder ) compared to earlier, and (recent problems are harder ) compared to earlier , so we should practice the problems such that it will be helpful for us to solve problems in actual contests

So can please update the ladders with standard problems of recent , or some problems where we learning something new by solving those problems

There are many good coders who can contribute to this you can take help :)

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2 months ago, # |
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The site has stopped working. Please look into this.

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2 months ago, # |
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Website is down. Could you please fix it?

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2 months ago, # |
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Sir plz fix the website

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2 months ago, # |
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site is down ,plz fix it

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2 months ago, # |
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C2 ladder website not working!!!

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2 months ago, # |
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why c2ladders is not live? please confirm.

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2 months ago, # |
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Now your link is showing

This site can’t be reached Check if there is a typo in c2-ladders.com. DNS_PROBE_FINISHED_NXDOMAIN

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2 months ago, # |
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the ladder is not available . Can someone help with it

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2 months ago, # |
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C2Ladders is not working.Getting following error This site can’t be reachedCheck if there is a typo in c2-ladders.com. DNS_PROBE_FINISHED_NXDOMAIN can you please check codemastercpp

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

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2 months ago, # |
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Why anyone would need any external website when CF itself has a nice sorting by rating/topic/solve-count feature?

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2 months ago, # |
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why its not working anymore?

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2 months ago, # |
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For people wondering C2 ladders has stopped working. Check this — https://acodedaily.com/ GitHub repo — https://github.com/i-pranav/ACDLadders

This is the recreated version of C2 ladders with updated data set.

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2 months ago, # |
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Great work... Eagerly waiting for the work to be completed...

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2 months ago, # |
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Site not working. Please check.

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

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