Hello, World!

Welcome to the PEG Online Judge. This site was created by members of Woburn Collegiate Institute's Programming Enrichment Group as a resource for competitive programmers everywhere. We also run PEGWiki, a site for information and tutorials of algorithms.

Currently, we have 1137 problems, 471761 submissions, 277 analyses, and support for 15 languages.

If you are new here, register an account and get familiar with the judge by solving A plus B. Alternatively, you can try a random problem that you haven't solved.

Announcements (See All)

Woburn Challenge 2018 Online Round 1

by Alex on Jan 17, 2018 - 6:39:17 am UTC
The Woburn Challenge is back for 2018! We've awarded thousands of dollars in prizes last year and are excited to do it again this year.

To be eligible for prizes, you must complete this year's registration form (see even if you have participated last year. If you have an existing PEG Judge username, you can continue using it. All Canadian high school students are eligible for prizes (you must be first registered through the aforementioned website), but everyone with a PEG Judge account is welcome to participate.

2018 Online Round 1

When: Friday, January 26th, 2018 from 3:30 pm to 6:30 pm ET
Where: The PEG Judge interface (
Format: 3 divisions, 3 hours, 4 problems, infinite submissions, and live feedback.
  • Top 8 Senior division winners: $100, $50, $25, $25, $25, $25, $25, $25
  • Top 4 Intermediate division winners: $50, $25, $25, $25
Full format and rules can be found at:
For more details, visit For questions, email [email protected].

Finally, please forward this to your friends (especially at other schools) who are interested in computer programming -- we want to get more students involved!

Good luck and enjoy the problems!

CCC/CCO 2017 Problems Added

by Alex on Aug 09, 2017 - 7:40:12 am UTC

Woburn Challenge Finals Results

by Alex on May 07, 2017 - 2:28:59 pm UTC
Thank you all who joined us for the Woburn Challenge 2016-17 on-site finals! Yesterday we witnessed 10 schools battle it out for the title of Woburn Challenge champion. In the end, Jason Yuen and William Wen of Pierre Elliott Trudeau High School came out on top of the senior and junior divisions respectively. Thank you to contestants and teachers alike, who stayed with us through to the end of the season.

The contest problems have been cloned to the main judge: J1, J2, J3/S1, J4/S2, J5/S3, S4, S5.
Problems, solutions, and test data will be posted shortly to this page. We truly hope that you enjoyed tackling them.

The senior division prizewinners are:
  • Jason Yuen of Pierre Elliott Trudeau High School ($250)
  • Brian Chau of Woburn Collegiate Institute ($200)
  • Joey Yu of Thornhill Secondary School ($150)
The junior division prizewinners are:
  • William Wen of Pierre Elliott Trudeau High School ($150)
  • William Fung and Sunny Lan of Richmond Hill High School ($100)
  • Jeffrey Gao and Richard Yi of William Lyon Mackenzie Collegiate Institute ($75)
Congratulations! We would love to hear your feedback about how to improve for next year, so please send them to [email protected] Have a great summer, and don't stop practicing!

Pinned Posts

Recent Comments