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Grader-chan has now turn 1 year old! It has been long journey since our debut contest. Until now, we held three contests, and provided over 200 problemset freely for everyone to do and share.
Thank you for supporting and trusting in our causes! May the next year be even better than before!

The 3rd Grader-chan contest problemset is out!
Editorial coming soon! (while it isn't out, please feel free to ask our problemsetters!)

Another hour to register for contest!
View live ranking at contest-ranking.gchan.moe

The 3rd Grader-chan Contest [Pre-POSN1] will be held on October 4th, 2025.

Shoutout to Revolution (revo.in.th) for sponsoring our contest!

We hope to see you!

Register: contest.gchan.moe/gc03

POSN1 season is coming up!
Request problemsets at our email: contact@gchan.moe or in our DMs!
Send us your PDF and license (preferably permissive license like CC-BY) and our team will get back to you!

Check this game out, it's kinda fun!
It's the game similar to CTFs, except it's mostly puzzle-based.

untitledpasswordfindinggame.mistertfy64.com

Grader-chan now has a complete collection of KU01 problems!

All 52 problems, free to practice at firefly.gchan.moe! (search the prefix "ku01_")

Thanks to KU01 team and Prof. Jittat Fakcharoenphol for the problems, and releasing the problems in CC0 license.

Heads up!
The scoreboard can be viewed on this site!
contest-ranking.gchan.moe

Register contest at contest.gchan.moe/gc02

The 2nd Grader-chan Contest is now open for registration!

Date: January 4th, 2025
Time: 07:00 PM - 10:30 PM UTC+7
Register now at contest.gchan.moe/gc02

Hope to see you!

The 2nd Grader-chan Contest will be held on January 4th, 2024.

Shoutout to DriteStudio for sponsoring our contest!

We hope to see you!