Update: As of 12:07pm EDT today, the affected users and their data should be restored. If there is any problem, please don't hesitate to contact us on slack or at admin@dmoj.ca. Again, we apologize for the inconvenience.

At approximately 10:10am EST today (October 15th), we experienced a database error that led to the loss of several thousand user accounts, as well as related submissions. We are in the process of restoring from a backup from yesterday (October 14th), 8pm EST. Users whose accounts were affected will be rolled back to their backed up state, while users who are not should see no changes.

To prevent possible collisions while restoring, we have temporarily blocked logins and new registrations.

We are sorry for any inconvenience this may cause.

Thanks for participating in the DMOPC '18 October contest!

The winners are:

1. xiaowuc1 (perfect score)
2. d (perfect score)
3. whzzt (perfect score)
4. fjzzq2002 (perfect score)
5. yjq_naiive (perfect score)

Editorials for each of the problems have been uploaded to the respective problem pages.

We hope you enjoyed the contest, and see you next month!

On Tuesday, October 9th, we'll be hosting the October DMOJ Monthly Open Programming Contest!

Anyone with a DMOJ account is welcome to participate, and anyone without one is welcome to register and participate.

Contestants may participate in any 3-hour window between noon EDT of Oct. 9th and noon EDT of Oct. 10th. Please see the contest page for more details.

See you soon!

We're excited to invite you to Another Contest - a new contest series being hosted on the DMOJ platform!

The first contest will run from October 12th to October 16th. Hope to see you there!

Thanks for participating in the DMOPC '18 September contest!

The winners are:

1. xiaowuc1 (perfect score)
2. y0105w49 (perfect score)
3. Egor (perfect score)
4. zhouzixiang2004 (perfect score)
5. wleung_bvg

Editorials for each of the problems have been uploaded to the respective problem pages.

We hope you enjoyed the contest, and see you next month!

On Tuesday, September 11th, we'll be hosting the September DMOJ Monthly Open Programming Contest!

Anyone with a DMOJ account is welcome to participate, and anyone without one is welcome to register and participate.

Contestants may participate in any 3-hour window between noon EDT of Sept. 11th and noon EDT of Sept. 12th. Please see the contest page for more details.

See you soon!

It's that time of the (school) year again, and to celebrate, we present the Back to School '18 contest! Get back into your tip top programming shape and start the school year with a new rating!

Back to School '18 will consist of 8 problems, with difficulty ranging between CCC Junior to IOI level.

You can choose a single 4 hour period between September 7 and September 9 EDT.

See the contest page for more details.

The University of Toronto Schools is hosting the second UTS Open! The problem setters for this contest are PlasmaVortex, zxyl, Cthulhu, and insect.

This is a 4-hour online contest, which allows contestants to participate in any 4-hour window from August 22nd to August 24th. Please see the contest page for more details.

Triway Cup is a contest that will be hosted at Triway Education (9011 Leslie St Unit 306, Richmond Hill, ON L4B 3B6) on the 26th of August, at 10AM - 1PM! Registration starts at 9AM.

There will be 8 problems, ranging from 3 to 30 points, between CCC and CCO level. Teams of up to 2 are allowed.

Problem writers/testers of this round are imaxblue and AQT.

Thank you to aeternalis1 and kassuno for testing!

There will be free prizes, food, tons of fun and it's an excellent way to get to know the community! During the contest, snacks will be provided. Lunch and solutions happen immediately after the contest.

The prizes will be $75, $50, and $25 for first, second, and third place in the live event.

Also, fill out the information please! Triway Cup Registration

Note: Prizes are only available for Canadian high school students.

Thanks for participating in the TLE '17 April contest!

The winners are:

1. xiaowuc1 (perfect score)
2. bqi343 (perfect score)
3. zhouzixiang2004
4. ct123098
5. wleung_bvg

Editorials for each of the problems will be uploaded to the respective problem pages.

We hope you enjoyed the contest!

We're excited to invite you to the eighth Thorndeau Logic Evaluation of the 2017-18 school year! The TLE '17 April contest will be a 3-hour virtual contest, which will allow contestants to participate in any 3-hour window from 12:00 PM EDT, April 27, 2018 to 12:00 PM EDT, April 28, 2018. Please see the contest page for more details.

Thanks for participating in the TLE '17 March contest!

The winners are:

1. y0105w49 (perfect score)
2. xiaowuc1
3. zhouzixiang2004
4. wleung_bvg
5. lg52931

Editorials for each of the problems will be uploaded to the respective problem pages.

We hope you enjoyed the contest, and see you next month!

We're excited to invite you to the seventh Thorndeau Logic Evaluation of the 2017-18 school year! The TLE '17 March contest will be a 3-hour virtual contest, which will allow contestants to participate in any 3-hour window from 12:00 PM EDT, March 30, 2018 to 12:00 PM EDT, March 31, 2018. Please see the contest page for more details.

As the academic year comes to an end, we'll be holding our final DMOPC in the form of the Don Mills Programming Gala.

This event will take place at Don Mills C.I. on Tuesday, April 24^th.

The contest will be split into three divisions of increasing difficulty, with prizes awarded to the top competitors. For interested competitors unable to attend the on-site event, we will also be hosting mirrors of the divisions, open for anyone to participate in.

Space is limited, so sign up soon! More details and registration options may be found here. You can find the results of last year's DMPG here.