How to get an account / participate in contests?

#### 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 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 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