Maximum AND

bitmasks, dfs and similar, divide and conquer, greedy, sortings

Min-Max Array Transformation

binary search, greedy, two pointers

Misha and Paintings

constructive algorithms, data structures, greedy, implementation, math

Xor-Subsequence (hard version)

bitmasks, data structures, dp, strings, trees

Xor-Subsequence (easy version)

bitmasks, brute force, dp, strings, trees, two pointers

Fighting Tournament

binary search, data structures, implementation, two pointers

Burenka, an Array and Queries

data structures, math, number theory

Impressionism

constructive algorithms, graphs, implementation, math

Permutation for Burenka

data structures, graph matchings, greedy, math, trees

Tonya and Burenka-179

data structures, greedy, math, number theory

Fibonacci Strings

greedy, implementation, math, number theory

Burenka and Traditions (hard version)

data structures, dp, greedy

Burenka and Traditions (easy version)

dp, greedy

Madoka and The First Session

constructive algorithms, flows, graph matchings, graphs, implementation

Madoka and The Best University

math, number theory

Madoka and The Corruption Scheme

combinatorics, constructive algorithms, greedy, math

Bags with Balls

combinatorics, dp, math, number theory

Swap and Maximum Block

bitmasks, data structures, dfs and similar, divide and conquer, dp

Chip Move

brute force, dp, math

Robot in a Hallway

data structures, dp, greedy, implementation, ternary search

Crop Squares

constructive algorithms, geometry, interactive, math

Long Way Home

data structures, divide and conquer, dp, geometry, graphs, greedy, shortest paths

2+ doors

2-sat, bitmasks, graphs, greedy

Monoblock

combinatorics, data structures, implementation, math

Path Prefixes

binary search, data structures, dfs and similar, trees

Build a Tree and That Is It

constructive algorithms, implementation, trees

Add Modulo 10

brute force, math, number theory

Color with Occurrences

brute force, data structures, dp, greedy, strings

Lost Array

bitmasks, combinatorics, constructive algorithms, dp, math

Cross Swapping

2-sat, data structures, dsu, greedy, matrices

Tournament Countdown

constructive algorithms, greedy, interactive, number theory, probabilities

Triameter

binary search, data structures, dfs and similar, trees

LCM Sum (hard version)

brute force, data structures, math, number theory, two pointers

LCM Sum (easy version)

binary search, brute force, combinatorics, math, number theory, two pointers

Empty Graph

binary search, constructive algorithms, data structures, greedy, shortest paths

Two Arrays

binary search, games, graph matchings

Recover the Tree

constructive algorithms, trees

XOR Triangle

bitmasks, brute force, constructive algorithms, dp, greedy, math

Rain

binary search, brute force, data structures, geometry, greedy, implementation, math

Color the Picture

constructive algorithms, greedy, math

Multiset of Strings

bitmasks, brute force, dp, fft, flows, graphs, math, meet-in-the-middle, trees

XOR Tree

bitmasks, data structures, dfs and similar, dsu, greedy, trees

Rorororobot

binary search, data structures, greedy, math

Recover an RBS

constructive algorithms, greedy, implementation, strings

Bugaboo

bitmasks, constructive algorithms, dp, number theory

Replace

binary search, data structures

Partial Virtual Trees

combinatorics, dfs and similar, dp, math, trees

DFS Trees

dfs and similar, dsu, graphs, greedy, sortings, trees

Difference Array

brute force, data structures, implementation, sortings

Doremy's IQ

binary search, constructive algorithms, greedy, implementation

Qpwoeirut and Vertices

binary search, data structures, dfs and similar, divide and conquer, dsu, greedy, trees

Chopping Carrots (Hard Version)

brute force, constructive algorithms, data structures, dp, greedy, math, number theory, two pointers

Chopping Carrots (Easy Version)

binary search, brute force, constructive algorithms, greedy, number theory

Qpwoeirut And The City

dp, flows, greedy, implementation

Mark and the Online Exam

bitmasks, constructive algorithms, interactive, probabilities

Mark and Professor Koro

binary search, bitmasks, brute force, combinatorics, data structures, greedy

Mark and Lightbulbs

combinatorics, constructive algorithms, greedy, math, sortings

Mark and His Unfinished Essay

brute force, implementation

Game of AI (hard version)

combinatorics, fft, math

Game of AI (easy version)

combinatorics, constructive algorithms, dp, fft, math

Mio and Lucky Array

constructive algorithms, fft, math, strings

Colouring Game

constructive algorithms, dp, games

Count Seconds

brute force, constructive algorithms, dp, graphs, implementation, math

Magical Array

constructive algorithms, hashing, implementation, math

Good Key, Bad Key

bitmasks, brute force, dp, greedy, math

Passable Paths (hard version)

data structures, dfs and similar, trees

Passable Paths (easy version)

dfs and similar, trees

Equate Multisets

constructive algorithms, data structures, greedy, math, number theory

Split Into Two Sets

dfs and similar, dsu, graphs

Points

combinatorics, data structures, implementation, math, matrices

Text Editor

brute force, dp, greedy, strings

Permutation Restoration

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

Schedule Management

binary search, greedy, implementation, two pointers

Puzzle

constructive algorithms, dp, greedy

Serega the Pirate

brute force, constructive algorithms

River Locks

binary search, dp, greedy, math

Helping the Nature

constructive algorithms, data structures, greedy

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