Each user can create their own domain. For example, teachers can create a domain for a course and add problems and students to that domain. Domains can also be used as team functionality.

By properly setting roles and their permissions, domains can be set as public or private.

The default domain is system. Users accessing UCup Challenge by Hydro directly will access this domain. Clicking the Hydro Logo will jump back to the system domain from any domain.

Each domain's problem bank, discussions, training, and contests are independent and autonomous.

UCup Challenge by Hydro uses HydroJudge for judging. For compilation parameters and current compiler versions, see the status page.

UCup Challenge by Hydro judge uses process CPU time to calculate time consumption. The time limit is specified by the test points in the problem.

UCup Challenge by Hydro judge uses the sum of process virtual memory and physical memory to calculate memory space consumption. The default memory space limit is 256MiB. If specifically specified in the problem, the limit is the memory space specified by the test points in the problem.

Unless otherwise specified, UCup Challenge by Hydro uses standard input/output (console I/O, screen I/O, STD I/O).

• Waiting Judging: The judging request is waiting to be fetched by the judge
• Fetched Judging: The judging request has been fetched by the judge and is preparing to start judging
• Compiling Judging: Currently compiling
• Judging Judging: Compilation successful, currently judging
• Accepted Passed: Program output is completely correct
• Wrong Answer Failed: Program output does not match the standard answer (excluding trailing spaces and trailing blank lines)
• Time Limit Exceeded Failed: Program runtime exceeded the problem limit
• Memory Limit Exceeded Failed: Program memory usage exceeded the problem limit
• Runtime Error Failed: Runtime error (such as array out of bounds, division by zero, arithmetic overflow, stack overflow, invalid pointer, etc.)
• Compile Error Failed: Compilation failed
• System Error Error: System error (if you encounter this issue, please provide feedback in the discussion area promptly)
• Canceled Other: Judging was canceled
• Unknown Error Other: Unknown error
• Ignored Other: Ignored

有“成绩取消”字样则说明管理员手动标记此记录为取消，可能违反了服务条款，比如代码被发现与其他用户的代码十分相似。

The following situations may occur:

• 1. Wrong programming language selected when submitting
• 2. Java main class name is not "Main"
• 3. For C/C++: see below
• 4. General compilation errors

Special reminders for C/C++ contestants:

• 1. __int64 should be written as long long type in GNU C++
• 2. main() return value must be defined as int, not void
• 3. The loop variable i in for statements will become invalid after statements like "for (int i = 0...) {...}"
• 4. itoa is not a standard ANSI function (this function does not exist in standard C/C++)
• 5. Using %lf format in printf is incorrect

我们精心挑选了一些题目组成了训练计划。单击导航栏的“训练”即可进入！

See configuration documentation for details

If you cannot log in, please carefully consider whether you remembered the username incorrectly. For example, the username you originally wanted to register may have already been taken, so you used a username with a prefix and/or suffix.

If you are certain that your account has been compromised or you have forgotten your account and/or password, please Reset Password or Find Username promptly.

Hydro's Markdown areas use CommonMark syntax and extend the following features:

• Mathematical formula support based on KaTeX syntax.
• Use @[](/user/uid) to mention users.
• Use ==text== to highlight text.
• Use ![alt](url =100x100) to set the size of embedded images.
• Use @[video](https://.../a.mp4) to embed video files.
• Use @[bilibili](BVxxx) to embed external videos.
• Use @[pdf](https://.../a.pdf) to embed PDF files.
• In problems/contests/homework/training, you can use the file://filename link format to reference corresponding attachments. (Recommended)
• Supports using a subset of HTML tags.