We will hold the <a href="https://atcoder.jp/contests/ahc_genai_test_2026">AHC GenAI Rules Trial Contest 2026</a> to evaluate proposed generative AI usage rules for future long-term AtCoder Heuristic Contests (AHCs). - Contest Page: https://atcoder.jp/contests/ahc_genai_test_2026 - Start Time: <a href="http://www.timeanddate.com/worldclock/fixedtime.html?iso=20261015T1900&p1=248">http://www.timeanddate.com/worldclock/fixedtime.html?iso=20261015T1900&p1=248</a> - Duration: 3 days - Writer: <a href="/users/wata_admin" class="username"><span class="user-unrated">wata_admin</span></a> - Unrated, no GP30 points Through this trial, we aim to evaluate the clarity and practicality of the rules, as well as their impact on the competitive experience. We encourage you to participate in the contest and would greatly appreciate your feedback through the Registration form!

We will hold <a href="https://atcoder.jp/contests/abc479">AtCoder Beginner Contest 479</a>. - Contest URL: https://atcoder.jp/contests/abc479 - Start Time: http://www.timeanddate.com/worldclock/fixedtime.html?iso=20261011T2100&p1=248 - Duration: 100 minutes - Writer: <img src="//img.atcoder.jp/assets/user/user-orange-1.png" class="user-rating-stage-m"><a href="/users/physics0523" class="username"><span class="user-orange">physics0523</span></a>, <img src="//img.atcoder.jp/assets/icon/crown_bronze.png"> <a href="/users/cn449" class="username"><span class="user-red">cn449</span></a> - Tester: <img src="//img.atcoder.jp/assets/user/user-orange-3.png" class="user-rating-stage-m"><a href="/users/sheyasutaka" class="username"><span class="user-orange">sheyasutaka</span></a>, <img src="//img.atcoder.jp/assets/user/user-orange-1.png" class="user-rating-stage-m"><a href="/users/physics0523" class="username"><span class="user-orange">physics0523</span></a> - Rated range: ~ 1999 - The point values: 100-200-300-400-450-500-600 We are looking forward to your participation!

We will hold <a href="https://atcoder.jp/contests/arc232">AtCoder Regular Contest++ 232</a>. - Contest URL: https://atcoder.jp/contests/arc232 - Start Time: http://www.timeanddate.com/worldclock/fixedtime.html?iso=20261010T2100&p1=248 - Duration: 150 minutes - Writer: <a href="/users/maroonrk" class="username"><span style="color:#869120;">maroonrk</span></a> - Tester: <img src="//img.atcoder.jp/assets/icon/crown_silver.png"> <a href="/users/snuke" class="username"><span style="color:#1000AC;">snuke</span></a>, <a href="/users/blackyuki" class="username"><span class="user-red">blackyuki</span></a> - Rated range: 1600 ~ 2999 - Point Values: 800-800-800-800-1100 We are looking forward to your participation!

We will hold <a href="https://atcoder.jp/contests/arc231">AtCoder Regular Contest 231</a>. - Contest URL: https://atcoder.jp/contests/arc231 - Start Time: http://www.timeanddate.com/worldclock/fixedtime.html?iso=20261004T2100&p1=248 - Duration: 120 minutes - Writer: <img src="//img.atcoder.jp/assets/user/user-orange-1.png" class="user-rating-stage-m"><a href="/users/Mitsubachi" class="username"><span class="user-orange">Mitsubachi</span></a> - Tester: <img src="//img.atcoder.jp/assets/icon/crown_bronze.png"> <a href="/users/Nyaan" class="username"><span class="user-red">Nyaan</span></a>, <img src="//img.atcoder.jp/assets/icon/crown_bronze.png"> <a href="/users/maspy" class="username"><span class="user-red">maspy</span></a> - Rated range: 1200 ~ 2799 - Point Values: 500-500-600-700-800-800 We are looking forward to your participation!

We will hold <a href="https://atcoder.jp/contests/abc478">AtCoder Beginner Contest 478</a>. - Contest URL: https://atcoder.jp/contests/abc478 - Start Time: http://www.timeanddate.com/worldclock/fixedtime.html?iso=20261003T2100&p1=248 - Duration: 100 minutes - Writer: <img src="//img.atcoder.jp/assets/user/user-yellow-4.png" class="user-rating-stage-m"><a href="/users/MMNMM" class="username"><span class="user-yellow">MMNMM</span></a>, <img src="//img.atcoder.jp/assets/user/user-orange-1.png" class="user-rating-stage-m"><a href="/users/KumaTachiRen" class="username"><span class="user-orange">KumaTachiRen</span></a>, <img src="//img.atcoder.jp/assets/icon/crown_bronze.png"> <a href="/users/toam" class="username"><span class="user-red">toam</span></a> - Tester: <img src="//img.atcoder.jp/assets/icon/crown_bronze.png"> <a href="/users/harurun4635" class="username"><span class="user-orange">harurun4635</span></a>, <img src="//img.atcoder.jp/assets/user/user-orange-1.png" class="user-rating-stage-m"><a href="/users/kyopro_friends" class="username"><span class="user-orange">kyopro_friends</span></a> - Rated range: ~ 1999 - The point values: 100-200-300-400-475-525-625 We are looking forward to your participation!