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Announcement for beta version

We provide [beta version]( Several functions has been added. Please try it!

AtCoder Regular Contest 059 / Beginner Contest 043 Announcement

Two contests [AtCoder Regular Contest 059]( and [AtCoder Beginner Contest 043]( will be held on this Saturday at the same time. You can participate in whichever contest you want. (However, you can't register to both competitions.) The last two tasks in ABC are the same as the first two tasks in ARC. - Time: August 13th (Saturday), [21:00 JST]( - Duration: 100 minutes - Number of Tasks: 4 - Writer:<a href="/user/sigma425" class="username"><span class="user-blue">sigma425</span></a>, <a href="/user/evima" class="username"><span class="user-unrated">evima</span></a> - Rating: 0-2799 for ARC, 0-1199 for ABC The point values are: - ARC: 200 - 400 (200) - 800 (400) - 800 (400) - ABC: 100 - 200 - 200 - 400 (200) We are looking forward to your participation!

AGC003 was Rescheduled

AGC003 was moved to 21st, Sunday (to avoid collision with other contests).

AtCoder testcases

All testcases of all future AtCoder official contests will be posted at

AtCoder Grand Contest 002 Announcement

[AtCoder Grand Contest 002]( will be held on Sunday. - Time: July 31st (Sunday), [21:00 JST]( - Duration: <font color="red">110</font> minutes - Number of Tasks: 6 - Writer: <a href="/user/sugim48" class="username"><span class="user-yellow">sugim48</span></a> - Rated: Yes We are looking forward to your participation! The point values are 200 (100), 400, 500, 1000, 1400, 1600.

AtCoder Rating System

The ratings were updated last Sunday, but it turned out that in the old rating system the ratings changed too much in a single contest. We changed the rating formula to fix this issue, and now the rating is calculated based on the new system. In AtCoder, when you participate in only a few contests your rating is much lower than your actual strength (so don't worry even if your current rating is very low). You need to participate in at least 10 contests in order to get accurate rating. We will publish the rating formula in the near future. Here is the table of colors: |Rating|Color| |:--:|:--:| |3600-3999|???| |3200-3599|???| |2800-3199|<span class="user-red">Red</span>| |2400-2799|<span class="user-orange">Orange</span>| |2000-2399|<span class="user-yellow">Yellow</span>| |1600-1999|<span class="user-blue">Blue</span>| |1200-1599|<span class="user-cyan">Cyan</span>| |800-1199|<span class="user-green">Green</span>| |400-799|<span class="user-brown">Brown</span>| |0-399|<span class="user-gray">Gray</span>|