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.

Thanks to Shayan

2197A — Friendly Numbers

2197B — Array and Permutation

2197C — Game with a Fraction

2197D — Another Problem about Beautiful Pairs

2197E2 — Interactive Graph(Hard Version)