| Term | Meaning |
|---|
| Problem | Prompt + resource limits + test cases. Public or contest-only. |
| Test case | Input/output pair. Hidden cases exist. Judge stops at first fail. |
| Submission | Code + language for a problem. Lifecycle: PENDING → verdict. |
| Event | API name for a contest: timed problems + leaderboard. UI says contest. |
| Custom input run | Execute against stdin without grading. The editor “Run” button. |
| User | Account. Admin manages problems/contests. Everyone else submits. |
| Language | Runtime config in judge image + DB row. ID goes in submission JSON. |
| Status | Meaning |
|---|
PENDING | In queue or running. Normal for a few seconds. |
ACCEPTED | All tests passed. |
WRONG_ANSWER | Output mismatch. |
TIME_LIMIT_EXCEEDED | Too slow. |
MEMORY_LIMIT_EXCEEDED | Too much RAM. |
RUNTIME_ERROR | Crash / nonzero exit. |
COMPILE_TIME_ERROR | Didn’t build. Check stderr. |
How judging works: Judge service.