Note: The text editorials will be provided by the authors of the round. This video tutorial acts as an additional resource for those who prefer video over text, not as a substitute for the text editorial.
2009A — Minimize!
Video
2009B — osu!mania
Video
2009C — The Legend of Freya the Frog
Video
2009D — Satyam and Counting
Video
2009E — Klee's SUPER DUPER LARGE Array!!!
Video
2009F — Firefly's Queries
Video
2009G — Yunli's Subarray Queries
Video