callmepandey's blog

How to build an online judge like Codeforces
By callmepandey, history, 13 months ago, In English

Hey Everyone, 

I am working on a college project that involves an online judge.

One of the features includes an IDE where we can run and test code on sample inputs and outputs. Codeforces is one such judge, and I was wondering how Codeforces compiles and runs our codes and tests them at such a high scale. Any insights would be helpful.

Thank you.

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13 months ago, # |
← Rev. 2   Vote: I like it +2 Vote: I do not like it

callmepandey

ye toh saar aapko MikeMirzayanov se pucchna hoga

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13 months ago, # |
  Vote: I like it +22 Vote: I do not like it

You could check out some open source OJ projects on GitHub, like syzoj. That may help you to build one quickly.

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13 months ago, # |
  Vote: I like it +23 Vote: I do not like it

Check DMOJ. Here are the docs: DMOJ Documentation

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13 months ago, # |
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Well, I had implemented simple online judge. I don't share code, but can give some tips. But it is run on only one server, there are no something like "load balancing". Just always running program, which takes next submission and checks it. And mysql database right on this server.

If we forget about web part, which in my case was on PHP, for implementing testing system you have to quite well know unix shell, and what can happen bad with running program and what to do in this case.

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13 months ago, # |
  Vote: I like it +13 Vote: I do not like it

++

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13 months ago, # |
  Vote: I like it +18 Vote: I do not like it

Here is an open source online code execution system (judge zero). You can use it to build a wide range of applications that need online code execution features. Check it out, it may help you.

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    13 months ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    Hi tawhidmonowar, thank you so much for replying. I tried installing Judge0 on my machine (Runs on M1 pro Chip) and when i try to run any code it returns.

    [Response 17/03/2023, 23:14:18] 200 OK
{
    "stdout": null,
    "time": null,
    "memory": null,
    "stderr": null,
    "token": "572762fb-4666-49aa-a5c5-17fcf4f457ab",
    "compile_output": null,
    "message": null,
    "status": {
        "id": 6,
        "description": "Compilation Error"
    }
}

    Everytime. The code and Language ID are fine.

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9 months ago, # |
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Here is mine. I created this using nern stack. Hope it helps. You can add/edit/delete problem + submit problem. I dont know how to implement and handle feature like Contest. Feel free to share any feedback or advice. Thank you

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6 weeks ago, # |
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I am interesting to hear your story with project if you done it, what did you learnt from it and what problems have you faced, I am about to create same thing for my graduate project.

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6 weeks ago, # |
  Vote: I like it +3 Vote: I do not like it

would you mind sharing your journey after you are done, I would also like to know it and build it using Flask or Django and try to showcase something like this in upcoming science exhibitions of my college.

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