Hello, Codeforces Community!

We are thrilled to invite you to participate in the replay of BUET IUPC 2026, Powered By Phitron on Codeforces! The replay will start on Feb/10/2026 15:00 (Moscow time) for 5 hours. You can find it here — Replay of BUET IUPC 2026, Powered By Phitron.

This contest follows ICPC-style rules and is unrated. Individual participation is allowed, but it is recommended to participate in 3 member teams for the best experience. The problems' difficulty range should offer good challenge for both division 1 and 2 participants, and interesting for ICPC Regional participants.

Acknowledgments:

• Special thanks to MikeMirzayanov for the powerful Codeforces and Polygon platforms.
• The problems were authored and thoroughly tested by DrSwad, ruhan.habib39, frosted, MH_Parag, ammelid, akifpathan, _skb_ and myself arman_ferdous.

We kindly ask participants who are already familiar with the problems to refrain from participating or discussing them before the contest ends.

Note: This contest is unrated.

We hope you enjoy the problem set, and best of luck to all participants!

Editorial: Find the solutions here.