New Year's 2019

It's 2019! A new year means setting New Year's resolutions, bettering yourself, and of course — a contest!

The problem writers this time will be Kirito, AvaLovelace, r3mark, and Eliden. Additionally, Kirito would like to apologize in advance for any poorly written flavour text: it's entirely his fault.

The New Year's Contest will be a 4-hour virtual contest. which will allow contestants to participate in any 4-hour window between 9 AM EST, January 4, 2019 and 9 PM EST, January 5, 2019. Of course, it is forbidden to use two accounts to participate, and it is also forbidden to discuss the problems and/or their solutions with other people during the entire contest period.

The pretest/systest format will not be used. This means that submissions will be judged on the full set of data during the contest. However, partial output will be disabled.

This contest will be rated for all participants who submit at least once.

Before the contest, you may wish to check out the tips and help pages.

The contest will run from Jan 4, 9 AM EST to Jan 5, 9 PM EST. It will consist of 8 problems in approximated increasing order of difficulty. The problems will be allotted different point values based on their difficulties.

After joining the contest, you proceed to the Problems tab to begin. You can also go to Users if you wish to see the rankings.

We have listed below some advice as well as contest strategies:

  • Start from the beginning. Ties will be broken by the sum of times used to solve the problems. Your last submission time will be used.
  • Remove all extra debugging code and/or input prompts from your code before submitting. The judge is very strict — most of the time, it requires your output to match exactly.
  • Do not pause program execution at the end. The judging process is automated. You should use stdin / stdout to perform input / output, respectively.
  • It is guaranteed that all the problems will be solvable with C++.

At the end of the contest, you may comment below to appeal a judging verdict. In the case of appeals, the decision(s) of DMOJ staff is final.

Good luck and Happy New Year!


Problem Points AC Rate Users
Snowball Fight 3 46.5% 226
Ball Sculpture 7 15.6% 96
Santa's Journey 7 6.7% 51
A Button Challenge 15p 5.5% 7
Best Hat in Town 15 20.8% 14
Buffer Zone 20 18.8% 3
The Order of the Fox 20 15.3% 23
Best Hat in Town II 25 20.1% 26


  • 1
    BaturaDima  commented on Jan. 12, 2019, 5:51 p.m.

    Where can I get test data for year2019p3? It is pretty interesting where my solution goes wrong.

    • 2
      Rimuru  commented on Jan. 13, 2019, 9:36 a.m.

      You cannot get the test data for problems, as they are stored in a database which is not accessible. If you would like help regarding your code, I recommend you join the DMOJ Slack.

  • 15
    Zeyu  commented on Jan. 6, 2019, 4:09 p.m.

    Just for curiosity, will there be editorials to the problems?

    • 3
      Kirito  commented on Jan. 13, 2019, 12:11 p.m.

      The authors are currently quite busy, but we do have editorials planned.

      • 2
        Zeyu  commented on Jan. 13, 2019, 5:55 p.m.

        Good to know, thank you for the response. Hope they are doing well and not too stressed out 🙂

  • 2
    JustinXu  commented on Jan. 5, 2019, 4:54 p.m.

    Is rating determined more by rank or by total points?

    • 19
      Rimuru  commented on Jan. 5, 2019, 6:01 p.m.

      It's pretty difficult to say how rating works... so I'll redirect you to the DMOJ's GitHub code for rating...

      A very nice alternative (if you are curious about your rating for contest) is to check out my dear friend Ninjaclasher's rating predictor here. The way it works is to add the contest link after this: For example, if you would like to check this contest, it can be done so by this link, which is

      • 2
        JustinXu  commented on Jan. 5, 2019, 6:17 p.m.

        Thanks for the detailed reply!

  • 32
    Kirito  commented on Jan. 4, 2019, 1:49 p.m.

    This is a reminder that while the contest says you are forbidden to use two accounts to participate, the implication is that you can only participate with a single account. Not 3, like a certain individual is currently suspected of doing.

    • 19
      Rimuru  commented on Jan. 4, 2019, 2:02 p.m.

      And then that individual will make a fourth, a fifth, ... \infty