Hello, Codeforces!
Our team is delighted to announce that the Massachusetts Computer Science Olympiad (MACSO) is back!
MACSO Summer 2025
-- the largest high school competition in Massachusetts to solve puzzling problems, meet ambitious peers passionate about CS, and grab some swag!
We hope and will try our best so our online participants will enjoy the event as much as our in-person contestants :)
We are excited to see you at MACSO Summer 2025 on July 27th at the Brookline Teen Center or online. The contest will start around 3 pm EST and last for 3 hours (**Exact timing will be announced later this week**)
Join the Qualification Round while it's still on!









How do I register? The form says that I'm already registered (from my previous participation).
And I can't submit either...
Hi macaquedev! I manually registered you for the contest. Let me know if it still doesn't work
Thanks, it works. Bit stumped by problem F! I liked problem D though.
How do I register?