umar.aligarh's blog

By umar.aligarh, history, 3 weeks ago, In English

I don't remember, but someone mentioned that there were lots of similar submissions to E1, when I looked at the suspicious submissions, they had one thing in common: memory consumed was equal to 8089600 bytes, so I ran some python and obtained these submissions(lets see how many are detected by plag-checker):

277426958, 277425890, 277425852, 277424914, 277424565, 277418774, 277418655, 277418511, 277418081, 277417714, 277417556, 277417035, 277416988, 277415986, 277415655, 277415207, 277414924, 277414655, 277413989, 277413413, 277413097, 277412884, 277412728, 277412417 rest I am commenting due to word limit

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3 weeks ago, # |
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    3 weeks ago, # ^ |
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    so more than 12% of E1 solutions are just cheaters. and thats only the stupid ones who didnt bother hiding it. actually crazy.

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

      If CF did not solve this problem, then only cheaters will remain on the site.

      Officially, there were only 210 correct solutions for E1 and most of the cheaters listed above (60-odd) are from that category. So this is closer to 30% rather than 12% when one filters out unofficial submissions.

      Anecdotally, based on all the recent reports of cheating, it would seem that 20-25% people are cheating on the critical problems (the ones that make the most difference in terms of the rankings) in each contest, that is just too much.

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        3 weeks ago, # ^ |
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        Already it would seem 20-25% people are cheating

        What is the source for this number?

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          3 weeks ago, # ^ |
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          well in the EPIC round, my final rank was around 1500 and after the reroll it is about 1100 so it can be estimated that there are around 20%-25% of participants are cheaters (at least in the top 1500)

          sorry for bad english

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            3 weeks ago, # ^ |
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            "At least in the top 1500" is very different from "in total" because cheaters are not uniformly distributed across the scoreboard.

            I would expect that most cheaters (especially the ones from the big groups) copy every leaked solution. Maybe they copy one or two fewer to make their result more plausible. But it's very hard to believe that someone would copy only problem A.

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          3 weeks ago, # ^ |
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    3 weeks ago, # ^ |
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    This is just crazy, can codeforces report some of the cheaters? I mean, there's a lot of websites charging money for codes and maybe codeforces can do something about it? This is just not fair for people who are trying to get higher ranks in a round using their own skills

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      3 weeks ago, # ^ |
      Rev. 2   Vote: I like it +18 Vote: I do not like it

      They really are doing something they caught over 2000 cheaters in the last 3 contests, so even though its frustrating, try to be patient. Mike really is trying his best for cf

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3 weeks ago, # |
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They are downvoting this like crazy

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3 weeks ago, # |
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Stupid cheaters. Period.

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3 weeks ago, # |
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I dont think they are that similar, I think there are less than 0.0014% cheaters here on codeforces. SO we should not bother brother bajelega

K_M_offical this dude is biggest cheater of all time, may god ban him from life

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3 weeks ago, # |
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how do u use python to check for similar submissions?

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    3 weeks ago, # ^ |
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    Used codeforces API to fetch all the submissions of contest-2001, then filtered according to memory used equal to some fixed bytes. (Used ChatGPT to generate this):

    import requests
    
    # Define the API endpoint
    url = "https://codeforces.net/api/contest.status?contestId=2001&asManager=false&from=1&count=100000"
    
    # Fetch the data from the API
    response = requests.get(url)
    
    # Check if the request was successful
    if response.status_code == 200:
        # Parse the JSON data
        data = response.json()
    
        # Extract the list of results
        results = data.get("result", [])
    
        # Filter the results based on the conditions
        filtered_ids = [
            item.get("id") for item in results
            if item.get("problem", {}).get("index") == "E1" and item.get("memoryConsumedBytes") == 8089600 and item.get("verdict")=="OK"
        ]
    
        # Print the filtered IDs
        print(filtered_ids)
    
        # Optionally, store the filtered IDs in a file or use them later in your program
        # For example, saving to a file:
        with open('filtered_ids.txt', 'w') as file:
            for id_ in filtered_ids:
                file.write(f"{id_}\n")
    else:
        print(f"Failed to fetch data. Status code: {response.status_code}")
    
    
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      3 weeks ago, # ^ |
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      oh thanks for giving the code have been wondering about this for quite a while have a great day!

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3 weeks ago, # |
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I always thought CF people were honest, until reading this article...

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3 weeks ago, # |
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You literally can't make this shit up. And of course these people use at least 2-3 languages per contest.

Why do anything when you literally can buy a spot in any contest in the top-100.

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3 weeks ago, # |
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Not to mention all the D problems getting hacked at the same testcase.