Maximum Control (medium)

Maximum Control (easy)

Encryption (hard)

动态规划 DP · 树状数组 · 动态规划优化

Encryption (medium)

Encryption (easy)

枚举 · 前缀和

Hyperspace Jump (hard)

Hyperspace Jump (easy)

Guard Duty (hard)

Guard Duty (medium)

动态规划 DP · 凸完全单调性（wqs 二分） · 反悔贪心

Guard Duty (easy)

Lightsabers (hard)

Lightsabers (medium)

Lightsabers (easy)

Mahmoud and Ehab and the even-odd game

Mahmoud and Ehab and the message

Mahmoud and Ehab and the wrong algorithm

Mahmoud and Ehab and another array construction task

枚举 · 素数判断,质数,筛法

Mahmoud and Ehab and the xor-MST

生成树 · 进制 · 前缀和

Mahmoud and Ehab and yet another xor task

排序 · 线性基

Check the string

Minimize the error

模拟 · 贪心

Subsequence Counting

Full Binary Tree Queries

Alternating Tree

Pathwalks

Bandit Blues

多项式 · Stirling 数 · 快速数论变换 NTT

Santa's Gift

线段树 · 树链剖分 · 期望

Tetris

模拟 · 概率论

Lecture Sleep

Chessboard

枚举

Pair Of Lines

Tufurama

数学 · 可持久化线段树 · 级数

k-substrings

字符串 · 哈希 hashing · 双指针 two-pointer

Partitions

Equator

模拟 · 概率论

Students in Railway Carriage

Make a Square

递归 · 枚举 · 概率论

Merge Equals

排序 · 优先队列 · 队列

Byteland, Berland and Disputed Cities

贪心 · 构造

Simple Cycles Edges

搜索 · 枚举 · 差分

Visible Black Areas

Alternating Sum

Destruction of a Tree

搜索

Cutting Rectangle

Frequency of String

Circles of Waiting

Splits

数学 · 贪心 · 递归

Messages

贪心 · 枚举 · 概率论

Paper Airplanes

Battleship