LoneFox's blog

By LoneFox, history, 4 days ago, In English,

The Qualification Round of the 2019 Facebook Hacker Cup is less than 48 hours away!

The round will begin on June 14th, 2019 at 10am PDT and will last for 72 hours (3 days). You can check the start time in your local timezone here.

The contest will be available here shortly before the round begins.

Everyone who solves at least one problem correctly will advance to Round 1, which will take place on June 29th. Please note that all submission judgments will only be revealed after the round ends. More details about rules and other information can be found here.

Registration will remain open until the end of the Qualification Round, so make sure to register if you haven't already, or confirm that your information is up to date if you have.

We wish you the best of luck, and hope that you enjoy the contest!

The corresponding Facebook post can be found here.

 
 
 
 
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3 days ago, # |
  Vote: I like it +121 Vote: I do not like it

Here we go again, that would be nice if you had sent an email regarding the start of registration/upcoming qualification beforehand.

Anyway thanks for posting this here, at least now I know there is something I shouldn't miss this weekend.

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3 days ago, # |
  Vote: I like it +34 Vote: I do not like it

Is there a way to collapse the top bar of the Facebook interface that shows the search bar and notifications for friend requests, Messenger, and posts in your feed? It would be nice to not have social media alerts directly next to the contest environment.

GLHF!

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    3 days ago, # ^ |
      Vote: I like it +20 Vote: I do not like it

    I guess you could probably Adblock/Ublock it somehow. (I think there's some functionality to block webpage elements given their ID or class.) Of course, you'd have to unblock the bar after the round, so it's a pretty rough solution.

    AFAIK, there's never been any way to disable the notifications. And then imagine receiving a message from your friend that's like "um, you aren't doing well on the contest right now :(".

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    2 days ago, # ^ |
      Vote: I like it +15 Vote: I do not like it

    lol imagine waving to your friend while he's doing fhc

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3 days ago, # |
  Vote: I like it +53 Vote: I do not like it

I deleted my facebook account last year and have been trying to make a new account so that I can participate for the past week. However, my efforts mostly seem to be wasted, I've tried different birthdays, different emails, different names (after failing with my default details). I keep getting a suspicious activity error, following which I give my Phone number and Photo (I've tried changing this too), however, I never heard back after this.

Is there a way I could participate without a Facebook Account?

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    2 days ago, # ^ |
      Vote: I like it +17 Vote: I do not like it

    Everybody must have a Facebook account to participate. Unfortunately, we're unable to expedite your request to open one — sorry!

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      2 days ago, # ^ |
        Vote: I like it +46 Vote: I do not like it

      following which I give my Phone number and Photo (I've tried changing this too), however, I never heard back after this

      This looks like something Facebook can and should help with.

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        2 days ago, # ^ |
          Vote: I like it +42 Vote: I do not like it

        Facebook has standard processes around account creation, which I'm afraid we're unable to personally circumvent.

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          45 hours ago, # ^ |
            Vote: I like it +46 Vote: I do not like it

          Having your new account locked by FB is a standard process of account creation at FB? Good to know.

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            44 hours ago, # ^ |
              Vote: I like it +5 Vote: I do not like it

            Hopefully you can believe that Facebook isn't trying to decrease its own user count for no particular reason.

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              43 hours ago, # ^ |
              Rev. 2   Vote: I like it +27 Vote: I do not like it

              >for no particular reason

              No, just the opposite. I believe FB wants only users that actively interact with the cashcow: marketing, or bring other users that will. Accounts created solely for the purpose of competing once a year, with no indication of engaging in regular social media activity (or even worse, with adblocks) don't fit there, so they're promptly autoblocked as "suspected bots".

              Getting people to give FB extra private info to sell is just a bonus.

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                11 hours ago, # ^ |
                  Vote: I like it +33 Vote: I do not like it

                I have my Facebook account solely to participate in Hacker Cup. I don't use it to engage in any social media activity (no friends, posts, messages, likes, or even an avatar). And I use an ad blocker. But I'm still not banned. What am I doing wrong?

                By the way, I've heard that Petr creates a new account before each year's Hacker Cup, and deletes it afterwards.

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    46 hours ago, # ^ |
      Vote: I like it +26 Vote: I do not like it

    I've never had a Facebook account (I think), but it still asks me for this. No way they manage to get me an account before the first round starts.

    I didn't participate last year since I didn't want to create a Facebook account. It seems this year I cannot even if I want to :/

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      34 hours ago, # ^ |
        Vote: I like it -27 Vote: I do not like it

      wow you're so cool

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      32 hours ago, # ^ |
        Vote: I like it +17 Vote: I do not like it

      why not create an account just to do FBHC, that's what I did. And all my friends are people who do CP so it wont be detected as a fake profile

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    35 hours ago, # ^ |
    Rev. 2   Vote: I like it -9 Vote: I do not like it

    Here’s an idea:

    1. set up virtual machine and use facebook through there (copy paste files back and forth)
    2. get residential proxy to your friend’s house or similar (NOT VPN!)
    3. all connection from VM goes thru residential proxy so your real ip doesn’t get leaked

    Then fb can’t use things like evercookie, browser fingerprint, ip address etc. to identify you as a bot/previously identified as bot user. Don’t use vpn or you’re probably flagged instantly for bot/hacker-like behavior. Also you probably shouldn’t submit real name and photos if they already have you in their blacklist of “bots”. Facebook will most likely think you’re a new user and you’ll be good to go!

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3 days ago, # |
  Vote: I like it +24 Vote: I do not like it

During the contest, are the subs judged on pretests, or just sample?

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

    From the rules

    When will I know whether my answers were right?

    We will judge the submissions after the round has ended.

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    2 days ago, # ^ |
      Vote: I like it +1 Vote: I do not like it

    The only live of evaluation of submissions is of their overall format — that is, if your submitted output file contains the wrong number of cases or if the required "Case #:" format itself isn't satisfied, you'll immediately receive a warning that it's formatted incorrectly.

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36 hours ago, # |
  Vote: I like it +7 Vote: I do not like it

What will it happen if my code is correct but my output is not correct (because I had copy pasted the input into vim and then all spaces were ignored and i didn't realise that in 6 minutes) ?

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    36 hours ago, # ^ |
      Vote: I like it +70 Vote: I do not like it

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    36 hours ago, # ^ |
      Vote: I like it +9 Vote: I do not like it

    I'm afraid that submission correctness is based on the submitted output file, so please be careful to upload the correct output file within the time limit!

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      35 hours ago, # ^ |
      Rev. 2   Vote: I like it +8 Vote: I do not like it

      Does this mean that you won't actually try and run the code file.

      I ask this because I also did a silly mistake, and submitted code with file I/O ( with ONLINE_JUDGE flag ) and some cerr statement, which usually work fine, atleast on Codeforces. I also read in rules, that it's ok to do file I/O. So, I just wanted to confirm with you. Thanks a lot.

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        35 hours ago, # ^ |
          Vote: I like it +9 Vote: I do not like it

        Yes, that's fine!

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        35 hours ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        So is it fine if your code does I/O from the file as long as the Output file is correct? I too forgot to remove the file statements :(

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          35 hours ago, # ^ |
            Vote: I like it 0 Vote: I do not like it

          Oh, read the reply after posting. Thanks for clearing the doubt.

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34 hours ago, # |
  Vote: I like it 0 Vote: I do not like it

I forgot to remove the file I/O statements will I be able to submit again, coz it's such a silly mistake everything else is correct.

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    34 hours ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    It got clarified :
    We don't run your code. Your solution is judged correct or incorrect based on the output file you've uploaded.
    Thanks,
    The Facebook Hacker Cup Team