umar.aligarh's blog

(Very) Similar submissons to E1 in div2 round 967
By umar.aligarh, history, 4 months 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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4 months ago, # |
  Vote: I like it +44 Vote: I do not like it

277412344, 277412005, 277411755, 277411550, 277411327, 277410979, 277410321, 277410177, 277409832, 277409824, 277409359, 277409074, 277409041, 277408703, 277408572, 277407753, 277407318, 277406742, 277405486, 277403754, 277402258, 277401666, 277401564, 277400636, 277399545, 277398866, 277397736, 277397082, 277396857, 277394969, 277394652, 277394299, 277393347, 277392523, 277390643 Honorable mention 277409802, 277414074

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    4 months ago, # ^ |
      Vote: I like it +30 Vote: I do not like it

    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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      4 months 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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        4 months ago, # ^ |
          Vote: I like it +3 Vote: I do not like it

        Already it would seem 20-25% people are cheating

        What is the source for this number?

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          4 months ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

          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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            4 months ago, # ^ |
              Vote: I like it +5 Vote: I do not like it

            "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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          4 months ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

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    4 months ago, # ^ |
      Vote: I like it +7 Vote: I do not like it

    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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      4 months 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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4 months ago, # |
  Vote: I like it +62 Vote: I do not like it

They are downvoting this like crazy

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4 months ago, # |
  Vote: I like it +10 Vote: I do not like it

Stupid cheaters. Period.

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4 months ago, # |
← Rev. 3   Vote: I like it -8 Vote: I do not like it

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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4 months ago, # |
  Vote: I like it 0 Vote: I do not like it

how do u use python to check for similar submissions?

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    4 months ago, # ^ |
      Vote: I like it +5 Vote: I do not like it

    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://mirror.codeforces.com/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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      4 months ago, # ^ |
        Vote: I like it +1 Vote: I do not like it

      oh thanks for giving the code have been wondering about this for quite a while have a great day!

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4 months ago, # |
  Vote: I like it 0 Vote: I do not like it

I always thought CF people were honest, until reading this article...

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4 months ago, # |
  Vote: I like it 0 Vote: I do not like it

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

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