Xenon's Attack on the Gangs

combinatorics, dfs and similar, dp, greedy, trees

Prefix Enlightenment

dfs and similar, dsu, graphs

Numbers on Tree

constructive algorithms, data structures, dfs and similar, graphs, greedy, trees

Dr. Evil Underscores

bitmasks, brute force, dfs and similar, divide and conquer, dp, greedy, strings, trees

The Cake Is a Lie

constructive algorithms, data structures, dfs and similar, graphs

Jeremy Bearimy

dfs and similar, graphs, greedy, trees

Tests for problem D

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

Two Fairs

combinatorics, dfs and similar, dsu, graphs

Nearest Opposite Parity

dfs and similar, graphs, shortest paths

Subset with Zero Sum

constructive algorithms, dfs and similar, graphs, math

Almost Same Distance

dfs and similar, graphs

Economic Difficulties

data structures, dfs and similar, dp, flows, graphs, trees

Secret Passwords

dfs and similar, dsu, graphs

Send Tree to Charlie

combinatorics, dfs and similar, dsu, trees

Harmonious Graph

constructive algorithms, dfs and similar, dsu, graphs, greedy, sortings

Wires

dfs and similar, graphs, greedy

Books Exchange (hard version)

dfs and similar, dsu, math

Sum Balance

bitmasks, dfs and similar, dp, graphs

0-1 MST

dfs and similar, dsu, graphs, sortings

Catowice City

2-sat, dfs and similar, graph matchings, graphs

The Maximum Subtree

dfs and similar, dp, graphs, trees

Alice and the Cactus

dfs and similar, graphs, math, probabilities

Tourism

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

The Light Square

2-sat, dfs and similar, greedy

Function Composition

dfs and similar

Coloring Edges

constructive algorithms, dfs and similar, graphs

Tiles Placement

constructive algorithms, dfs and similar, trees

Treasure Island

dfs and similar, dp, flows, hashing

Unstable String Sort

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

Koala and Notebook

data structures, dfs and similar, graphs, shortest paths, strings, trees

Cow and Snacks

dfs and similar, dsu, graphs

Bits And Pieces

bitmasks, dfs and similar, dp, greedy

Indie Album

data structures, dfs and similar, hashing, string suffix structures, strings, trees

Graph Traveler

brute force, data structures, dfs and similar, dp, graphs, implementation, math, number theory

Dynamic Diameter

*special problem, data structures, dfs and similar, divide and conquer, trees

Add on a Tree: Revolution

constructive algorithms, dfs and similar, implementation, trees

Tree Painting

dfs and similar, dp, trees

Vus the Cossack and a Graph

dfs and similar, graphs, greedy, implementation

Daleks' Invasion (medium)

dfs and similar, graphs, shortest paths, trees

Complete Mirror

constructive algorithms, dfs and similar, dp, hashing, implementation, trees

Plus from Picture

dfs and similar, implementation, strings

The Awesomest Vertex

data structures, dfs and similar

Short Colorful Strip

combinatorics, dfs and similar, dp

Cover it!

dfs and similar, dsu, graphs, shortest paths, trees

Recover it!

dfs and similar, graphs, greedy, number theory, sortings

Minimal Segment Cover

data structures, dfs and similar, divide and conquer, dp, greedy, implementation, trees

Nauuo and Circle

combinatorics, dfs and similar, dp, trees

News Distribution

dfs and similar, dsu, graphs

Permutation recovery

constructive algorithms, data structures, dfs and similar, graphs, greedy, math, sortings

0-1-Tree

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

Ugly Pairs

dfs and similar, greedy, implementation, sortings, strings

Serval and Rooted Tree

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

Neko and Flashback

constructive algorithms, dfs and similar, graphs

Neko Performs Cat Furrier Transform

bitmasks, constructive algorithms, dfs and similar, math

Palindrome XOR

dfs and similar, graphs

Frog Jumping

dfs and similar, math, number theory

Graph Without Long Directed Paths

dfs and similar, graphs

Queen

dfs and similar, trees

Lynyrd Skynyrd

data structures, dfs and similar, dp, math, trees

Privatization of Roads in Treeland

binary search, constructive algorithms, dfs and similar, graphs, greedy, trees

Edgy Trees

dfs and similar, dsu, graphs, math, trees

Spanning Tree with One Fixed Degree

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

Knapsack

dfs and similar, dp, greedy

Gourmet choice

dfs and similar, dp, dsu, graphs, greedy

Connect

brute force, dfs and similar, dsu

Power Tree

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

Tree Cutting (Hard Version)

combinatorics, dfs and similar, dp, trees

Tree Cutting (Easy Version)

dfs and similar, trees

Tree

data structures, dfs and similar, dp, graphs, trees

Lunar New Year and a Wander

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

Kilani and the Game

dfs and similar, graphs, implementation, shortest paths

Johnny Solving

constructive algorithms, dfs and similar, graphs, math

GCD Counting

data structures, dfs and similar, dp, number theory, trees

Andrew and Taxi

binary search, dfs and similar, graphs

Cookies

binary search, data structures, dfs and similar, dp, games, trees

Construct a tree

binary search, constructive algorithms, dfs and similar, graphs, greedy, trees

Sum in the tree

constructive algorithms, dfs and similar, greedy, trees

Beautiful Graph

dfs and similar, graphs

Tree with Maximum Cost

dfs and similar, dp, trees

Minimal Diameter Forest

constructive algorithms, dfs and similar, greedy, trees

Harder Satisfiability

2-sat, dfs and similar, graphs

Choosing Two Paths

dfs and similar, dp, greedy, trees

Multihedgehog

dfs and similar, graphs, shortest paths

Up and Down the Tree

dfs and similar, dp, trees

Three Pieces

dfs and similar, dp, shortest paths

Upgrading Cities

dfs and similar, graphs

Company

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

Fun with Integers

dfs and similar, graphs, implementation, math

Sergey and Subway

dfs and similar, dp, trees

Bmail Computer Network

*special problem, dfs and similar, trees

Decorate Apple Tree

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

Hyperspace Highways

dfs and similar, graphs, trees

Intersecting Subtrees

dfs and similar, interactive, trees

Leaf Sets

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

Network Safety

dfs and similar, dsu, graphs, math, sortings

Maximum Matching

bitmasks, brute force, dfs and similar, dp, graphs

Valid BFS?

dfs and similar, graphs, shortest paths, trees

Sources and Sinks

bitmasks, brute force, dfs and similar

Hidden Bipartite Graph

binary search, constructive algorithms, dfs and similar, graphs, interactive

King Escape

dfs and similar, graphs, implementation