NIMO Summer Contest Rules

Last updated March 2016


Summer Contest participants must be entering grade 12 or below (or equivalent) in the current school year, and be at most 19 years old on January 1 of the current school year. Participants may not discuss problems with anybody during the competition period. The NIMO Competition Committee reserves the right to disqualify any individuals suspected of outside communication or any other form of cheating.

Contest Format

Problem 1 will be made available online at 5:00 PM PDT (8:00 PM EDT) on the contest date. There are two ways to advance to another problem: submitting an answer, either correct or incorrect, will give access to the next problem, and participants may also skip a problem to proceed to the next problem. The problems are in roughly increasing order of difficulty. No aids other than scratch paper, graph paper, rulers, compasses, protractors, and computers may be used. Computers are permitted only for viewing contest problems, submitting answers, skipping to a different problem, or viewing the live scoreboard. All answers are positive integers.

During the contest, there will be a live leaderboard updated approximately every 10 seconds with the top 20 scores, their corresponding user ID's, and their last problem viewed. This leaderboard will stop updating once 70% of the contest time has passed, and will not resume updating until the contest is over.


The problems are weighted as described on the Contests page. Generally this will be Problem #1 = 1 point, Problem #2 = 2 points, etc. Tiebreaking is done by score on the last problem, score on the second to last problem, and so on. In the event that there is still a tie, a penalty equal to the sum of the number of minutes spent on each correctly answered problem will be used to break the tie.

These weights may be adjusted prior to the contest. Any changes will be announced well in advance, and may be viewed on the Contests & Rules page.