Quarantine Computing Contest

Welcome to the first (and hopefully last) Quarantine Computing Contest! This contest will be COVID-19 themed.

The problem setters are qwertytown4life, Encodeous, maxcruickshanks, lookcook, and ArtyKing12!

Big thanks to sushi, feliser, Dan13llljws, Riolku, kdrkdr, Maillew, richardzhang, sjay05, and Plasmatic for testing, feedback, and assistance with the problems!

The contest will run from May 22nd, 00:00 EDT to May 25th, 00:00 EDT. You will have a 2.5-hour window to solve 6 problems. There will be an additional 7-th bonus problem (Problem 0) for those who are just getting started with programming. The difficulty of the problems ranges from CCC Junior to CCC Senior.

Here are the parameters of the contest:

  • Contest duration: 2.5 hours.
  • Number of problems: 7, full feedback (you will see the results of your submissions instantly). Problem 0 will be worth 30 points, and the rest will be worth 100 points. Some problems will offer partial marks in the form of subtasks.
  • The problems are not guaranteed to be in ascending order of difficulty.
  • Scoreboard will be hidden until your window is over.
  • This contest is unrated.
  • No incorrect submission penalty.
  • There is a submission limit of 50 submissions per problem.
  • Ties in score will be broken by the sum of the last submission times that increased your score.
  • Checkers for problems: Unless otherwise specified, standard.
  • All problems are guaranteed to be solvable in C++.

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

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

  • 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.
  • Python users are recommended to use PyPy 2/3 over Python 2/3 when submitting.

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.


Problem Points AC Rate Users Editorials
QCC P0 - Thermometer 3 54.9% 144 Editorial
QCC P1 - Quarantine Games 10 29.8% 36
QCC P2 - Online School 5p 33.1% 79 Editorial
QCC P3 - Cohorts 10p 36.3% 46
QCC P4 - Genetic Sequencing 5p 53.4% 47
QCC P5 - Vaccine Delivery 12 16.2% 25
QCC P6 - Freedom! 7p 45.1% 49 Editorial


  • 19
    EpicChadGamer  commented on May 18, 2021, 6:00 p.m.

    Are the editorials out?

    • 9
      kdrkdr  commented on May 21, 2021, 6:22 p.m.

      no, editorials are editorials

    • 9
      Tony1234  commented on May 18, 2021, 6:12 p.m.


  • 24
    Aaeria  commented on May 18, 2021, 5:53 p.m.

    Is it rated?

    • 34
      piddddgy  commented on May 18, 2021, 6:24 p.m.

      i rate u a solid 10/10 <3

      • 13
        Aaeria  commented on May 20, 2021, 10:24 a.m.

        • 12
          piddddgy  commented on May 20, 2021, 2:02 p.m.


      • 8
        ArtyKing12  commented on May 20, 2021, 10:13 a.m.


    • 17
      qwertytown4life  commented on May 18, 2021, 6:12 p.m.

      The contest is NOT rated. I apologize for this not being on the contest page. It will be updated ASAP.