Hard Way

geometry

Covering Circle

geometry

Special Positions

combinatorics, divide and conquer, fft, math

Two Arrays

bitmasks, brute force, combinatorics, greedy, hashing, math, two pointers

Anonymity Is Important

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

Repetitions Decoding

constructive algorithms, implementation, sortings

Great Sequence

brute force, greedy, sortings

Treasure Hunt

graphs, interactive

Treasure Hunt

graphs, interactive

Treasure Hunt

graphs, interactive

Treasure Hunt

graphs, interactive

Treasure Hunt

graphs, interactive

Treasure Hunt

graphs, interactive

Treasure Hunt

graphs, interactive

Treasure Hunt

graphs, interactive

Treasure Hunt

graphs, interactive

Treasure Hunt

graphs, interactive

Treasure Hunt

graphs, interactive

Two Posters

brute force, data structures, greedy, two pointers

Colorful Operations

brute force, data structures, implementation

Big Brush

constructive algorithms, data structures, greedy, implementation

Inversion Graph

data structures, dsu, graphs, math

Odd Swap Sort

data structures, math, sortings

Reverse

constructive algorithms, greedy, math

Minimize Inversions Number

data structures, greedy, math, sortings

Birthday

constructive algorithms, greedy, math

Towers

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

Best Pair

binary search, brute force, implementation

Yet Another Minimization Problem

dp, greedy, math

Andrew and Stones

greedy, implementation

MEX and Array

brute force, dp, greedy, math

Sorting Parts

brute force, sortings

Closest Pair

data structures, greedy

Cars

2-sat, constructive algorithms, dfs and similar, dsu, graphs, greedy, sortings

Infinite Set

bitmasks, dp, math, matrices, number theory, strings

Differential Sorting

constructive algorithms, greedy

Avoid Local Maximums

greedy

Min Or Sum

bitmasks, greedy

Fibonacci Additions

brute force, data structures, hashing, implementation, math

Fair Share

constructive algorithms, data structures, dfs and similar, graph matchings, graphs

Finding Zero

constructive algorithms, interactive, math

OKEA

constructive algorithms

Fortune Telling

bitmasks, math

Reverse and Concatenate

greedy, strings

Perfect Matching

data structures, divide and conquer, interactive, trees

Spanning Tree Queries

binary search, data structures, dfs and similar, dsu, graphs, greedy, math, sortings, trees

Make Them Equal

dp, greedy

Kill the Monster

brute force, math

Minority

greedy

Div. 7

brute force

Distance Tree (hard version)

binary search, dfs and similar, shortest paths, trees

Distance Tree (easy version)

binary search, data structures, dfs and similar, graphs, shortest paths, trees

New Year Concert

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

Strange Test

binary search, bitmasks, brute force, dp, math

Roof Construction

bitmasks, constructive algorithms

ABC

implementation

Fun with Even Subarrays

dp, greedy

Min Max Swap

greedy

Making It Bipartite

flows, graph matchings, graphs, number theory

Expected Components

combinatorics, math, number theory, probabilities

Flipping Range

constructive algorithms, dp, greedy, number theory

Paint the Middle

dp, greedy, sortings, two pointers

Range and Partition

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

And Matching

bitmasks, constructive algorithms

GCD Arrays

greedy, math, number theory

Download More RAM

brute force, greedy, sortings

Spaceship Crisis Management

binary search, data structures, geometry, sortings

Groceries in Meteor Town

binary search, data structures, dsu, trees

Game on Sum (Hard Version)

combinatorics, dp, games, math

Game on Sum (Easy Version)

combinatorics, dp, games, math

Grid Xor

constructive algorithms, greedy, implementation, interactive, math

Peculiar Movie Preferences

greedy, strings

Meximum Array

binary search, constructive algorithms, greedy, implementation, math, two pointers

Not Splitting

geometry, graphs, greedy, implementation, shortest paths

Not Escaping

data structures, dp, implementation, shortest paths, two pointers

Not Adding

brute force, dp, math, number theory

Not Assigning

constructive algorithms, dfs and similar, number theory, trees

Not Sitting

games, greedy, sortings

Not Shading

constructive algorithms, implementation

A Random Code Problem

combinatorics, dp, math, number theory, probabilities

Black and White Tree

dfs and similar, greedy, trees

Martial Arts Tournament

binary search, brute force, greedy, math

Monsters And Spells

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

Minor Reduction

greedy, strings

Equidistant Letters

constructive algorithms, sortings

Cats on the Upgrade (hard version)

binary search, data structures, dfs and similar, graphs, trees

Cats on the Upgrade (easy version)

brute force, data structures, dfs and similar, divide and conquer, dp, graphs, trees

Binary Spiders

bitmasks, data structures, implementation, math, sortings, trees

Road Optimization

dp

Elementary Particles

brute force, greedy, sortings

Ancient Civilization

bitmasks, greedy, math

MinOr Tree

bitmasks, dfs and similar, dsu, graphs, greedy

Interacdive Problem

binary search, constructive algorithms, interactive

Masha-forgetful

brute force, constructive algorithms, dp, hashing, implementation, strings

Palindromes Coloring

binary search, greedy, sortings, strings

Division by Two and Permutation

constructive algorithms, flows, graph matchings, greedy, math

Make AP

implementation, math

Plus One on the Subset

math

Middle Duplication

data structures, dfs and similar, greedy, strings, trees

Robot Cleaner Revisit

implementation, math, probabilities