[How to get an account / participate in contests?](http://atcoder.jp/posts/2) [AtCoder's Contest Format](http://atcoder.jp/posts/1) [AtCoder's Testcases](https://www.dropbox.com/sh/arnpe0ef5wds8cv/AAAk_SECQ2Nc6SVGii3rHX6Fa?dl=0) - [AtCoder's Rating System](https://www.dropbox.com/sh/zpgcogxmmu84rr8/AADcw6o7M9tJFDgtpqEQQ46Ua?dl=0) - [AtCoder Race Ranking](https://docs.google.com/spreadsheets/d/1T-hKu_vIh8l4EiW6XTWOvP0evzsWj0f45JNNgou21Cc/edit#gid=695896678)
#### How to get an account? 1. Click "Sign up" at the top-right corner . 2. Fill your information and click "Sign up". User ID is your handle used in this website. It should consist of letters, digits, and underscores, and the length should be between 3 and 16, inclusive. User name is currently not used, but we recommend to fill it with the same string as User ID. 3. Click "Sign up" (blue button). #### How to recover the password? 1. Go to https://practice.contest.atcoder.jp/password/recovery. 2. Fill your User ID and email address, and click the blue button. 3. Now you received an email with title "[AtCoder]パスワード再発行の案内". (Unfortunately the email is written in Japanese - we will fix it.) 4. Click the link in the email. 5. Type your new password twice and click the blue button. 6. Now you can use your new password. #### How to participate in contests? 1. Go to the contest website. For example, if you want to participate in AGC 001, click "AtCoder Grand Contest 001" in "Upcoming Contests" box. 2. Now you are in http://agc001.contest.atcoder.jp/. 3. Click "Join in AtCoder Grand Contest 001". (You can do this during the contest, but we recommend you to do it before the contest to save your time. Your rating will not change if you don't submit anything during the contest.) 4. When the contest starts, go to the contest website and solve problems! 5. You can practice the usage of this judge at http://practice.contest.atcoder.jp/.
Hello! I'm <a href="/user/rng_58" class="username"><span class="user-admin">rng_58</span></a>. I'm the contest manager in AtCoder. AtCoder is a programming contest website based in Japan. From this weekend, we will provide problem statements in both English and Japanese and AtCoder will be an international programming competition! There are three types of official contests in AtCoder: - AtCoder Grand Contest (AGC). This is our best contest. The problems will have high originality and require interesting observations. - AtCoder Regular Contest (ARC). The problems may be a bit typical compared to AGC problems, but still we think most of you can enjoy them and they are good for practice. - AtCoder Beginner Contest (ABC). This is mainly targeted for those who are new to competitive programming. The problems will be easy and educational. Usually, our contests will be held at 21:00 (JST) on Saturday. We are planning to hold AGC about twice a month, and in other weeks we will hold both ARC and ABC (you can choose in which contest to participate). We have a rating system and users will be colored according to their rating. There are eight colors in total (except for newcomers' black and admins' purple). Can you guess what colors are used? We hope you will enjoy AtCoder Contests!