[ARC219B] Reverse Permutation

[ARC219C] Traveling Door-to-Door Salesman (Elevator)

动态规划 DP · 贪心

[ARC219D] Grid Game

博弈论

[ARC219E] Equal Distribution

构造

[ARC219F] Range Division

[ARC219G] Traveling Door-to-Door Salesman (Stairs)

[ARC220A] Sum of Reciprocals of Squares

[ARC220B] Incomplete Shuffle

并查集 · 欧拉回路

[ARC220C] Range Increment

动态规划 DP · 贪心 · 堆 · 斜率维护技巧 slope trick · 反悔贪心

[ARC220D] Long Trail

数学 · 图论 · 构造 · Ad-hoc

[ARC220E] popcount ≥ K

[ARC221A] Two Arithmetic Progressions

最大公约数 gcd · 扩展欧几里德算法 · 莫比乌斯反演 · 容斥原理

[ARC221B] Two-Powered Sum

动态规划 DP · 组合数学 · 容斥原理 · Stirling 数

[ARC221C] Two Deques Sorting

[ARC221D] Two Balanced Subtrees

[ARC221E] Two Increasing Sequences

[ARC222A] Colorful Intervals

构造

[ARC222B] Circular RPS

[ARC222C] 2 Directions vs 4 Directions

动态规划 DP

[ARC222D] Shift and Add

状压 DP

[ARC222E] XOR Matching

快速沃尔什变换 FWT

[ARC222F] Triple Transformation

魔法使い高橋君

圧縮

グラフ

图论 · 生成树

ストラックアウト

动态规划 DP · 单调队列

迷子の高橋君

期望

数字列をカンマで分ける問題

Colorful MST

图论 · 生成树 · 构造

Many Swaps Sorting

排序 · 构造

Paired Parentheses

Ancient Tree Record

Black Cats Deployment

Unicyclic Graph Counting

n^p mod m

递归 · 进制 · 中国剩余定理 CRT

最適二分探索木

Turn Right

Volume Control

Painting the Floor

Irregular Contest

3Match

Cards

Don't Think Seriously!

Be Together

Vinculum

Bit Map

U・N・C・O

Pyramid

Ninja of Train

Batch Style Mastermind