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Welcome to WYKOJ!

Recent Solves

Time User Task Language
2026-08-29 20:59:38 wy24180 - Hayden Cheung Z2624 - 6ix 7even C++
2026-08-28 22:02:49 wy24180 - Hayden Cheung C2511 - Odd Ones Out C++
2026-08-28 21:58:43 wy24180 - Hayden Cheung C2623 - Nice Pairs C++
2026-08-28 21:28:31 wy24180 - Hayden Cheung C2512 - Case-sensitive C++
2026-08-28 21:26:37 wy24180 - Hayden Cheung C2624 - Snail at the bottom C++
2026-08-28 16:10:35 wy24084 - Li Junxi B006 - Trigonometric Simplification C++
2026-08-28 13:59:41 wy24084 - Li Junxi B005 - Quadrants C++
2026-08-28 13:55:31 wy24084 - Li Junxi B004 - Pythagoras' Theorem C++
2026-08-28 13:54:43 wy24084 - Li Junxi B002 - Arithmetic Operators C++
2026-08-28 13:47:22 wy24084 - Li Junxi B001 - Hello Darkness My Old Friend C++
2026-08-28 11:38:23 wy24125 - matttt B005 - Quadrants C++
2026-08-28 11:36:53 wy24125 - matttt B004 - Pythagoras' Theorem C++
News!

🎉 More Performance Improvements!
Database is colocated with the server (from AWS RDS). Queries are now substantially faster.

13 August 2026

🎉 Performance Improvements!
Contest and submission pages are now rendered faster.

8 August 2026

🎉 Task Page Improvements!
You can now browse tasks by category and sort the task list by number of solves. Tasks can now also have subtasks that depend on other subtasks being solved.

2 August 2026

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