Three Days Grace

data structures, dp, greedy, math, number theory, two pointers

Almost Triple Deletions

data structures, dp, greedy

The Third Problem

combinatorics, constructive algorithms, math

Long Binary String

bitmasks, math, matrices, meet-in-the-middle, number theory

Equal Reversal

constructive algorithms, graphs, implementation, math

PermutationForces II

brute force, combinatorics, greedy, sortings, trees, two pointers

Fixed Point Guessing

binary search, constructive algorithms, interactive

Too Many Constraints

2-sat, constructive algorithms, graphs, implementation

Coloring

brute force, combinatorics, constructive algorithms, dp, geometry, graphs, greedy, implementation, math

Guess The String

binary search, constructive algorithms, interactive

awoo's Favorite Problem

binary search, constructive algorithms, data structures, greedy, implementation, strings, two pointers

Maximum Product?

brute force, combinatorics, dp, greedy, implementation, math, two pointers

Fishingprince Plays With Array Again

brute force, data structures, geometry, math

Tree Recovery

brute force, constructive algorithms, dfs and similar, dsu, graphs, trees

Placing Jinas

combinatorics, math

Permutation Graph

binary search, constructive algorithms, data structures, divide and conquer, greedy, shortest paths

Fishingprince Plays With Array

constructive algorithms, greedy, implementation, math

Ambiguous Dominoes

constructive algorithms, dfs and similar, graphs

Tree Queries (Hard Version)

constructive algorithms, dfs and similar, dp, greedy, trees

Tree Queries (Easy Version)

brute force, constructive algorithms, dfs and similar, dp, greedy, trees

Zero Path

brute force, data structures, dp, graphs, greedy, shortest paths

I Might Be Wrong

binary search, greedy, two pointers

Outermost Maximums

data structures, greedy

Decinc Dividing

brute force, data structures, divide and conquer, dp, greedy

Keshi in Search of AmShZ

graphs, greedy, shortest paths

Fake Plastic Trees

dfs and similar, dp, greedy, trees

Gambling

data structures, dp, greedy, math

2^Sort

data structures, dp, sortings, two pointers

K-Set Tree

combinatorics, dfs and similar, dp, math, trees

Number of Groups

data structures, dfs and similar, dsu, graphs, greedy, sortings

Max GEQ Sum

binary search, constructive algorithms, data structures, divide and conquer, implementation, two pointers

Sum of Substrings

brute force, constructive algorithms, greedy, math, strings

Count the Trains

binary search, data structures, greedy, sortings

Shifting String

graphs, math, number theory, strings

Price Maximization

binary search, greedy, math, two pointers

ANDfinity

bitmasks, brute force, constructive algorithms, dfs and similar, dsu, graphs

Lena and Matrix

data structures, dp, geometry, shortest paths

Infected Tree

dfs and similar, dp, trees

Manipulating History

constructive algorithms, greedy, strings

Koishi's Unconscious Permutation

fft, math

Become Big For Me

combinatorics, constructive algorithms, greedy, math, number theory

Cute number

binary search, brute force, data structures, dsu, implementation, math

Sanae and Giant Robot

binary search, brute force, data structures, dsu, greedy, sortings

Railway System

constructive algorithms, graphs, greedy, interactive, sortings

The Enchanted Forest

brute force, greedy

The Ultimate LIS Problem

data structures, greedy

Permutation Weight (Hard Version)

constructive algorithms, greedy

Permutation Weight (Easy Version)

constructive algorithms, dfs and similar, dsu

Bring Balance

brute force, constructive algorithms, greedy

Linguistics

greedy, implementation, sortings, strings

Hard Cut

constructive algorithms, dfs and similar, divide and conquer, math

Euclid Guess

constructive algorithms, flows, graph matchings, math, number theory

Diverse Segments

data structures, two pointers

MEX vs DIFF

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

Traps

constructive algorithms, greedy, sortings

Column Swapping

brute force, constructive algorithms, greedy, implementation, sortings

MCMF?

data structures, flows, graphs, greedy, sortings, two pointers

Unordered Swaps

constructive algorithms, dfs and similar, graphs, greedy, math, sortings, trees

Circular Spanning Tree

constructive algorithms, implementation, trees

LIS or Reverse LIS?

constructive algorithms, greedy, implementation, math

Unique Occurrences

data structures, dfs and similar, divide and conquer, dp, dsu, trees

Labyrinth Adventures

data structures, dp, matrices, shortest paths

Required Length

brute force, dfs and similar, dp, hashing, shortest paths

Lenient Vertex Cover

dfs and similar, divide and conquer, dsu, graphs, trees

Moving Chips

bitmasks, dp, greedy

Dog Walking

brute force, greedy, math

Binary String

binary search, greedy, strings, two pointers

Formalism for Formalism

bitmasks, dp, math

Typical Party in Dorm

bitmasks, combinatorics, dp, strings

Toss a Coin to Your Graph...

binary search, dfs and similar, dp, graphs

Rooks Defenders

data structures, implementation

Tokitsukaze and Good 01-String (hard version)

dp, greedy, implementation

Tokitsukaze and Gems

dp, math

Tokitsukaze and Beautiful Subsegments

data structures

Tokitsukaze and Permutations

dp, math

Tokitsukaze and Two Colorful Tapes

constructive algorithms, dfs and similar, graphs, greedy

Tokitsukaze and Meeting

data structures, implementation, math

Tokitsukaze and Strange Inequality

brute force, data structures, dp

Maximum Crossings (Hard Version)

data structures, divide and conquer, sortings

Maximum Crossings (Easy Version)

brute force

Sorting Pancakes

dp

Vlad and Unfinished Business

dfs and similar, dp, greedy, trees

Replace With the Previous, Minimize

dsu, greedy, strings

Remove Directed Edges

dfs and similar, dp, graphs

Desktop Rearrangement

data structures, greedy, implementation

Breaking the Wall

binary search, brute force, constructive algorithms, greedy, math

Anti-Theft Road Planning

bitmasks, constructive algorithms, divide and conquer, greedy, interactive, math

Power or XOR?

bitmasks, combinatorics, math, number theory

Lost Arithmetic Progression

combinatorics, math, number theory

Palindrome Basis

brute force, dp, math, number theory

PermutationForces

data structures, greedy

Zigu Zagu

constructive algorithms, data structures, greedy

Cross Xor

constructive algorithms, graphs, math, matrices

Checker for Array Shuffling

constructive algorithms, dfs and similar, graphs

Array Shuffling

constructive algorithms, graphs, greedy

notepad.exe

binary search, constructive algorithms, greedy, interactive

Cyclic Rotation

constructive algorithms, greedy, implementation, two pointers

Permutation Counting

brute force, combinatorics, dp, fft, math

Preorder

combinatorics, divide and conquer, dp, dsu, hashing, sortings, trees

Insert a Progression

brute force, constructive algorithms, greedy