Construct an Array

constructive algorithms

Game on Growing Tree

binary search, dfs and similar, divide and conquer, dp, games, implementation, trees

Minimum Influence

binary search, data structures, greedy, implementation, math, sortings, two pointers

Good Schedule

dp, greedy

Arrange the Numbers in a Circle

constructive algorithms, implementation, math

Digit String

greedy, implementation, math

Optimal Purchase

implementation, math

The Endians

dp, trees

Wowee Binary String

combinatorics, dp, strings

Roadworks

binary search, data structures, dp, greedy, two pointers

Load Unbalancing

binary search, bitmasks, dp, greedy

Deconstruction Tree

combinatorics, data structures, dp, graphs, trees

Me When Median Problem

binary search, greedy

We Be Flipping (Hard Version)

constructive algorithms, dp, greedy

We Be Flipping (Easy Version)

constructive algorithms, greedy

Absolute Cinema

greedy, math

Slimes on a Line

brute force, greedy, math

Momoyo and the Network

binary search, dfs and similar, dfs and similar, divide and conquer, divide and conquer, dp, trees

Amanojaku and Sequence (Hard Version)

combinatorics, data structures, implementation, math

Amanojaku and Sequence (Easy Version)

combinatorics, math

Sanae, Cross and Color

binary search, data structures, implementation

Cirno and Number (Hard Version)

binary search, dfs and similar, dp, greedy, implementation

Cirno and Number (Easy Version)

binary search, brute force, dp, greedy, implementation

Remilia Plays Soku

games, implementation

Marisa Steals Reimu's Takeout

greedy, implementation

Fallen Leaves

dfs and similar, dp, dp, trees, trees

Drowning

binary search, data structures, math

It Just Keeps Going Sideways

binary search, data structures, data structures, dp, dp, greedy, greedy, math, math

It All Went Sideways

binary search, data structures, dp, greedy

Palindromex

binary search, brute force, constructive algorithms, data structures, greedy, implementation, two pointers

Snowfall

constructive algorithms, math

Party Monster

greedy

Koshary

implementation, math

Stop Spot

implementation, strings, trees

Inversion Invasion

math, number theory

Mental Monumental (Hard Version)

data structures, greedy, math, two pointers

Reserved Reversals

constructive algorithms, dp, greedy, math

Mental Monumental (Easy Version)

binary search, data structures, greedy, math, two pointers

Everything Everywhere

greedy, math, math, number theory, number theory

Disturbing Distribution

greedy, math

Simple Problem

brute force, graphs, greedy, number theory

String Cutting

binary search, brute force, brute force, greedy, hashing, string suffix structures, string suffix structures, strings, strings

Covering Points with Circles

constructive algorithms, geometry, math

Exceptional Segments

bitmasks, brute force, math

Red-Black Pairs

dp, greedy

Alternating String

brute force, greedy

A Number Between Two Others

greedy, math

Zhily and Mex and Max

constructive algorithms, greedy, math, sortings

Zhily and Array Operating

constructive algorithms, greedy

Zhily and Colorful Strings

divide and conquer, fft, math

Zhily and Permutation

data structures, divide and conquer, trees

Zhily and Cycle

graphs, greedy

Zhily and Signpost

chinese remainder theorem, dfs and similar, math, number theory, trees

Zhily and Barknights

binary search, data structures, dp, math, sortings, two pointers

Zhily and Bracket Swapping

constructive algorithms, greedy

Counting Sort?

brute force, combinatorics, dp

Statistics on Tree

binary search, brute force, dfs and similar, dfs and similar, divide and conquer, graphs, trees, trees

Building Tree

data structures, divide and conquer, dsu, graphs, graphs, implementation

Seek the Truth

binary search, bitmasks, constructive algorithms, interactive

Permutation Construction

constructive algorithms, data structures, sortings

Median Partition

dp, math

Artistic Balance Tree

greedy, sortings

A Wonderful Contest

brute force, dp, math

OIE Excursion

greedy

Blocked

greedy, sortings

Weird Chessboard

constructive algorithms, math

MEX Replacement on Tree

data structures, implementation, math, trees

Coloring a Red Black Tree

dfs and similar, dp, greedy, math, probabilities, trees, trees

Unique Values (Hard version)

binary search, bitmasks, constructive algorithms, interactive

Unique Values (Easy version)

binary search, constructive algorithms, divide and conquer, interactive, math

Grid L

brute force, constructive algorithms, math, number theory

The 67th Iteration of "Counting is Fun"

implementation, math

The 67th Tree Problem

constructive algorithms, implementation, trees

The 67th XOR Problem

binary search, bitmasks, brute force

The 67th OEIS Problem

constructive algorithms, greedy, greedy, greedy, math, math, number theory

The 67th Permutation Problem

constructive algorithms, greedy, math

The 67th 6-7 Integer Problem

greedy, math

The 67th Integer Problem

brute force, games, implementation, math

Closer

dfs and similar, dp, trees

Down the Pivot

combinatorics, dp, math, trees

Interval Game

bitmasks, combinatorics, constructive algorithms, dp, games, games, greedy, greedy, math, probabilities

Definitely Larger

binary search, constructive algorithms, data structures, graphs, greedy, sortings

Flip the Bit (Hard Version)

greedy, implementation, math

Grid Covering

chinese remainder theorem, math, number theory

Flip the Bit (Easy Version)

greedy, implementation

The Equalizer

math

THU Packing Puzzle

greedy

Course Wishes

greedy

Maze

trees

Research

games

Star Map

constructive algorithms, data structures, geometry, greedy, sortings

EXPloration, EXPloitation, and Gain Some EXPerience!

bitmasks, brute force, dp, greedy, implementation

Oriented Journey

bitmasks, brute force, communication, constructive algorithms, graphs, interactive, trees

RReeppeettiittiioonn

binary search, brute force, implementation, math, number theory

Interval Mod

constructive algorithms, dp, greedy, math

Special Problem

*special problem, brute force, games, interactive

You Are a Robot

*special problem, *special problem

Double Vision

*special problem

Anomaly

*special problem, communication

Numbers

*special problem