Welcome to the third annual WOSS Dual Olympiad! This is the senior division of the individual round of the contest.

The contest organizer is Riolku.

The problem setters this time are 404, Max_Ding, and pewpew.

Thanks to Bobliu, Joelfu, JojoTheWarrior, linx, Marshmellon, Snowfall, and tofu for testing and feedback on the problems.

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

The senior round will consist of 3 problems, the difficulty of which may range anywhere from CCC Senior 1 to CCC Senior 4.

You will have 60 minutes to complete the contest. After the contest window begins, you may begin at any time. Once you enter the contest, your personal timer will start counting down and you will be able to submit until 60 minutes from when you started, or until the hard deadline (00:00:00 EST of January 18th), whichever comes first.

After joining the contest, you may proceed to the Problems tab to begin. Here are the parameters of the contest:

• Contest duration: 60 minutes.
• Number of problems: 3, full feedback (you will see the results of each submission instantly).
• Each problem will be worth 100 points.
• Some problems offer partial marks in the form of subtasks.
• Scoreboard will be hidden until after your window.
• No incorrect submission penalty.
• A maximum of 50 submissions will be allowed per problem.
• Ties in score will be broken by the last submission time that increased your score.
• This contest is unrated.