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This is a brief guide to making a solved.ac account and registering for an Arena contest.

The Arena contests are held on the Baekjoon Online Judge(BOJ) platform. Please kindly note that:

  • The BOJ is mainly a problem archive like Kattis, and is a host to many community contests mainly in the Republic of Korea. The solved.ac Arena contests are held on the BOJ platform, but the BOJ is not the Arena itself.
  • Though the translation of the BOJ is still work in place, the interface related to solving problems are fully available in English. The Arena problem statements will be in English if the contest notice states so.

Registering to the Contest Platform

First, we will make a BOJ account if you do not have one. Navigate to the BOJ registration page and refer to the image below to fill out the form.

BOJ registration page. The bottom section contains forms: from top to bottom, there are input boxes for handle, bio, password, password confirmation, affiliation, email, a captcha, and a checkbox that asks for receiving emails. The top section contains following information: "If you already have an account, please sign in. By signing up, you agree to Baekjoon Online Judge's terms of use, and privacy policy. If you do not want your handle to be searchable in Google search, please use a handle that is not used elsewhere. You can change your handle’s search exposure settings after signing up. Handle cannot be changed after registration."

If the site is in Korean, please navigate to the bottom of the page and change the language to English.

Bottom of any BOJ page. There is a link titled "English (Beta)" at the bottom right of the page.

Change the Default Language

The default language for problem descriptions is Korean. For your convenience, please change it to English by navigating to the BOJ display settings.

The top of the BOJ display settings. The first set of settings is the problem description language setting. The first option is Korean, the second is English, and the last one is Original Language. Please set the option to English.

You are now ready to participate in the Arena contests! Please navigate to the Contests section of the BOJ to see the list of upcoming contests.

But you need to register to the Arena to be a 'rated participant'.

Linking Your Account to solved.ac

In order to register to the Arena contest, you need to link your BOJ account to your solved.ac account.

First, you have to allow solved.ac to access your BOJ submission data. Navigate to the BOJ account link settings and click the blue button. This will enable solved.ac to access your submission data.

The BOJ account link settings. There is a big blue button at the bottom. The text above the button says: "solved.ac is a service made by @shiftpsh, a BOJ user. This service enables you to access problem difficulty informations and users’ tier ratings. Please press the button below to enable solved.ac to access the following data: your handle, and your submission results. Your solution codes are not provided to solved.ac."

Signing In to solved.ac

After linking, please navigate to solved.ac. Click the 'Sign in' button at the top right corner of the page and sign in with your BOJ account.

The top bar of the solved.ac website.

The BOJ will ask you to allow solved.ac to access your account. Click the blue button to allow access.

The BOJ to solved.ac sign in page. There is a red button at the bottom left and a blue button at the bottom right, that says 'Cancel' and 'Sign in', respectively. The text above the button says: "You are now signing in to solved.ac with your BOJ account. Currently signed in as: shiftpsh."

Registering to the Arena

After logging in to solved.ac, you can register to the Arena. Navigate to the Arena page.

The solved.ac Arena listing page.

Clicking the red Register button will register you to the Arena. You are now a rated participant in the Arena contests!