Mishka and Interesting sum

data structures

Beautiful Mirrors

data structures, dp, math, probabilities

Complete the Projects (easy version)

greedy

Array and Operations

flows, graph matchings, number theory

Recovering BST

brute force, dp, math, number theory, trees

GCD Queries

constructive algorithms, interactive, number theory

Pencils and Boxes

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

Omkar and Duck

bitmasks, constructive algorithms, interactive, math

Permutation Shift

brute force, combinatorics, constructive algorithms, dfs and similar, dsu, graphs, math

Points on Plane

constructive algorithms, divide and conquer, geometry, greedy, sortings

Best Pair

binary search, brute force, implementation

Timofey and Black-White Tree

brute force, dfs and similar, divide and conquer, graphs, greedy, math, shortest paths, trees

Decryption

constructive algorithms, implementation, math, number theory

Common Number

binary search, combinatorics, dp, math

More Wrong

divide and conquer, interactive

Bracket Walk

data structures, greedy, strings

XOR Break --- Solo Version

bitmasks, constructive algorithms, greedy

Friends and Subsequences

binary search, data structures

Graph Coloring

dfs and similar, dp, graphs

MEX vs DIFF

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

Number of Components

combinatorics, data structures, dp, math

The Human Equation

greedy, implementation

Sleepy Game

dfs and similar, dp, games, graphs

Game on Sum (Easy Version)

combinatorics, dp, games, math

Flying Sort (Easy Version)

dp, greedy, two pointers

Vasya and Beautiful Arrays

brute force, dp, number theory

Monsters

brute force, data structures, dfs and similar, dsu, graphs, greedy

Kirk and a Binary String (hard version)

data structures, greedy, math, strings

Skyline Photo

data structures, divide and conquer, dp

New Year's Puzzle

brute force, dp, graph matchings, greedy, sortings

Send Boxes to Alice (Hard Version)

constructive algorithms, greedy, math, number theory, ternary search, two pointers

OpenStreetMap

data structures, two pointers

New Year and Conference

binary search, data structures, hashing, sortings

Minimax

constructive algorithms, greedy, strings

Pictures with Kittens (hard version)

data structures, dp

Beautiful Subarrays

data structures, divide and conquer, strings, trees

How Many Paths?

dfs and similar, dp, graphs, trees

Increase Sequence

combinatorics, dp

Treelabeling

bitmasks, constructive algorithms, dfs and similar, games, greedy, implementation, trees

Mahmoud and a xor trip

bitmasks, constructive algorithms, data structures, dfs and similar, dp, math, trees

Counting Rhyme

dp, math, number theory

Funny Substrings

data structures, hashing, implementation, matrices, strings

Red-Blue Operations (Easy Version)

binary search, greedy, implementation, math

Euclid's nightmare

bitmasks, dfs and similar, dsu, graphs, greedy, math, sortings

Bear and Tree Jumps

dfs and similar, dp, trees

The LCMs Must be Large

bitmasks, brute force, constructive algorithms, math, number theory

Potion Brewing Class

dfs and similar, math, number theory, trees

Tree with Small Distances

dp, graphs, greedy

Rectangular Congruence

constructive algorithms, number theory

Portals

data structures, dp, greedy, implementation, sortings

Anya and Cubes

binary search, bitmasks, brute force, dp, math, meet-in-the-middle

Array Collapse

data structures, divide and conquer, dp, trees

Pathwalks

data structures, dp, graphs

Berland Beauty

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

ConstructOR

bitmasks, chinese remainder theorem, combinatorics, constructive algorithms, math, number theory

Domino (hard version)

constructive algorithms, implementation, math

Preorder

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

Game of Stones

bitmasks, dp, games

Clique Partition

brute force, constructive algorithms, graphs, greedy, implementation

Speedrun

brute force, dfs and similar, dp, graphs, greedy, math, sortings, two pointers

Promising String (hard version)

data structures, implementation, math, strings

Hossam and (sub-)palindromic tree

brute force, data structures, dfs and similar, dp, strings, trees

Editor

data structures, implementation

Breaking Good

dfs and similar, dp, graphs, shortest paths

Timofey and rectangles

constructive algorithms, geometry

MST Unification

binary search, dsu, graphs, greedy

Flexible String Revisit

combinatorics, dp, math, probabilities

Playlist for Polycarp (easy version)

bitmasks, combinatorics, dp

Shovels Shop

dp, greedy, sortings

Range Deleting

binary search, combinatorics, data structures, two pointers

Paint the Tree

dp, sortings, trees

Count Binary Strings

data structures, dp

You Are Given a WASD-string...

brute force, data structures, dp, greedy, implementation, math, strings

Guess Game

bitmasks, data structures, games, math, probabilities, sortings, strings, trees

Sad powers

binary search, math, number theory

Colorings and Dominoes

combinatorics, dp, greedy, math

String

brute force, constructive algorithms, hashing, implementation, string suffix structures, strings

Sheikh (Hard Version)

binary search, bitmasks, brute force, greedy, implementation, two pointers

Tree Constructing

constructive algorithms, graphs

Grime Zoo

brute force, greedy, implementation, strings

Learning to Paint

binary search, data structures, dfs and similar, dp, greedy, implementation, sortings

Perfect Groups

dp, math, number theory

Neko and Aki's Prank

dp, greedy, trees

Sum over all Substrings (Hard Version)

bitmasks, divide and conquer, dp, dsu, greedy, implementation, strings

Two strings

binary search, hashing, strings, two pointers

Counting Binary Strings

combinatorics, dp, math

Rain

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

Red-Black Number

dfs and similar, dp, implementation, math, meet-in-the-middle

Counting Shortcuts

data structures, dfs and similar, dp, graphs, shortest paths

Unstable String Sort

data structures, dfs and similar, dsu, graphs, greedy, implementation, strings

Carry Bit

combinatorics, math

Wi-Fi

data structures, dp, greedy

Lunar New Year and Red Envelopes

data structures, dp

Underground Lab

constructive algorithms, dfs and similar, graphs

Treasure Hunting

binary search, dp, greedy, implementation

Weird journey

combinatorics, constructive algorithms, dfs and similar, dsu, graphs

Space Harbour

data structures, implementation, math, sortings

Subway Pursuit

binary search, interactive, probabilities

Candy Party (Hard Version)

bitmasks, constructive algorithms, dp, greedy, implementation, math

Hot Start Up (hard version)

data structures, dp