In preparation for the 2015 CCO, bruce has put together a set of problems for all to practice for the CCO.

The contest consists of 3 challenging algorithmic problems roughly similar in difficulty to the Canadian Computing Olympiad.

The format is a virtual contest with 4 hours to solve 3 problems. The duration of the entire contest will be 4 days.

Important: You will be able to access the problems from the main judge. This is intentional, to allow students to keep solving the problems after their 4 hour timer is up. However, if it's your first time doing this contest, please access it from the contest page to keep things fair for everyone. Thank you!

https://dmoj.ca/contest/ccoprep1

Enjoy!

All of CCO 2013 problems have been added.

https://dmoj.ca/problems/?category=24

Thanks to JeffreyZ for typing up all the statements!

Update: All solutions for 2015 are complete.

We are in the process of making detailed, high quality editorials for 2015 CCC (we may add past contests too at a later time). You can find them in Problems -> problem statement -> Read editorial.

• J1 - Special Day
• J2 - Happy or Sad
• J3 - Rövarspråket
• J4 - Wait Time
• J5 - π-day
• S1 - Zero That Out
• S2 - Jerseys
• S3 - Gates
• S4 - Convex Hull
• S5 - Greedy For Pies

...and more to come!

If you see mistakes in the editorials, or feel that they aren't detailed enough, open a ticket on the problem and we'll improve them. You can also do that if you want to contribute editorials for any year.

You are just an ordinary programmer having a decent day while enjoying your early morning cup of tea. Suddenly, you notice two strange guys running around on the street in panic. You decide to go over to them and ask what's up. Congratulations, you are now a part of their squad. After a lot of discussion, you find out that these guys are going after the one and only cheesecake recipe, and since you love cheesecake, you agree to help them out!

The contest will run from February 23th, 2015 at 3:00PM EST to February 24th, 11:59PM EST, within which you will have 3 hours to complete the contest.

Visit the contest page for more details.

We have added all CCC 2015 problems to the DMOJ.

You may find them here: https://dmoj.ca/problems/?search=ccc+%2715.

The JOI (Japanese Olympiad of Informatics) Open Contest 2014 problems have been added to the DMOJ.

https://dmoj.ca/problems/?category=23

Many of them use signature grading, unlike most of the DMOJ problemset.

JOI '14 problem 4, Migration, was an output-only task that was judged against other contestant submissions. Since the DMOJ doesn't have the required infrastructure (and it's not worth adding it for one problem), Migration has not been added.

Like charts? Statistics? Charts and statistics? We do too. That's why we've compiled relative statistics regarding submissions in _{actually used} languages on the DMOJ.

Update: The latest statistics are available at https://dmoj.ca/stats/language/

Are you interested in how other people did on the CCC, and are curious about your chances of making it into the CCO? Here's an unofficial poll where you can enter your score and check out others' scores. There's no penalty or anything if you lie, but there's really no point in doing so either, as the poll is anonymous.

"It would be really easy to put fake votes and make everyone panic but we're trusting people not to do that. Only vote if you wrote the Senior!"

(poll courtesy of nullptr)