Hello, Codeforces!

Welcome to OICon OJ! This is a new Online Judge developed by me. Do not forget to register your account for it!

In season 2026-2027, we (the KDOI Team) plan to hold a series of at least five rounds of contests on OICon OJ. Read this post to learn more about it.

We will hold the first round — KDOI Tournament 2026 Preliminary Round — on Aug/30 at 14:00 — 16:00 (UTC +8). If you are interested in experiencing CNOI-style contests, do not miss these contests! Note that this round will be the only written contest in the series. Both English and Chinese statements will be provided.

The setters and testers of the round are Error_Yuan, sszcdjr, and paulzrm.

See you on the OICon OJ!