Almost All

constructive algorithms, trees

Magic Tree

*special problem, data structures, dp, trees

Dynamic Diameter

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

Daleks' Invasion (hard)

data structures, dsu, graphs, trees

Daleks' Invasion (medium)

dfs and similar, graphs, shortest paths, trees

Daleks' Invasion (easy)

graphs, trees

Add on a Tree: Revolution

constructive algorithms, dfs and similar, implementation, trees

Add on a Tree

trees

Tree Painting

dfs and similar, dp, trees

Fedor Runs for President

data structures, dp, trees

Serge and Dining Room

binary search, data structures, graph matchings, greedy, implementation, math, trees

Irrigation

binary search, data structures, implementation, sortings, trees, two pointers

Complete Mirror

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

Cover it!

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

Nauuo and Circle

combinatorics, dfs and similar, dp, trees

Minimal Segment Cover

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

Ehab and the Big Finale

constructive algorithms, divide and conquer, graphs, implementation, interactive, trees

Anagram Paths

dp, implementation, trees

Strange device

binary search, interactive, math, trees

0-1-Tree

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

Tree Generator™

data structures, implementation, trees

Neko and Aki's Prank

dp, greedy, trees

Leaf Partition

dp, trees

Serval and Rooted Tree

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

Niyaz and Small Degrees

data structures, dp, trees

Queen

dfs and similar, trees

Lynyrd Skynyrd

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

Double Tree

data structures, divide and conquer, shortest paths, trees

Edgy Trees

dfs and similar, dsu, graphs, math, trees

Privatization of Roads in Treeland

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

Matches Are Not a Child's Play

data structures, trees

Greedy Subsequences

data structures, dp, trees

Power Tree

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

Legendary Tree

binary search, interactive, trees

Tree Cutting (Hard Version)

combinatorics, dfs and similar, dp, trees

Tree Cutting (Easy Version)

dfs and similar, trees

Sasha and Algorithm of Silence's Sounds

data structures, trees

Sasha and Interesting Fact from Graph Theory

brute force, combinatorics, dp, math, trees

Tree-Tac-Toe

constructive algorithms, games, trees

Nearest Leaf

data structures, trees

Tree

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

GCD Counting

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

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

Vladislav and a Great Legend

combinatorics, dp, trees

Minimum Diameter Tree

constructive algorithms, implementation, trees

Tree with Maximum Cost

dfs and similar, dp, trees

Minimal Diameter Forest

constructive algorithms, dfs and similar, greedy, trees

Max Mex

data structures, trees

The Fair Nut and the Best Path

data structures, dp, trees

Ehab and a weird weight formula

data structures, trees

Ehab and a component choosing problem

dp, greedy, math, trees

Decorate Apple Tree

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

Vasya and Maximum Matching

dp, trees

Company

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

Vasya and a Tree

data structures, trees

Tree and XOR

strings, trees

Intersecting Subtrees

dfs and similar, interactive, trees

Choosing Two Paths

dfs and similar, dp, greedy, trees

Random Forest Rank

dp, graph matchings, math, trees

Bmail Computer Network

*special problem, dfs and similar, trees

Up and Down the Tree

dfs and similar, dp, trees

Split the Tree

binary search, data structures, dp, greedy, trees

Sergey and Subway

dfs and similar, dp, trees

Euler tour

constructive algorithms, trees

Moonwalk challenge

data structures, strings, trees

Interstellar battle

math, probabilities, trees

Hyperspace Highways

dfs and similar, graphs, trees

Last chance

data structures, flows, graph matchings, trees

Region Separation

combinatorics, dp, number theory, trees

The Shortest Statement

graphs, shortest paths, trees

Leaf Sets

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

You Are Given a Tree

data structures, dp, trees

Valid BFS?

dfs and similar, graphs, shortest paths, trees

Recovering BST

brute force, dp, math, number theory, trees

Pisces

data structures, flows, trees

Mobile Phone Network

dfs and similar, dsu, graphs, trees

Raining season

data structures, divide and conquer, trees

Road Projects

dfs and similar, dp, trees

Tree

fft, graphs, trees

Mars rover

dfs and similar, graphs, implementation, trees

Military Problem

dfs and similar, graphs, trees

Dominant Indices

data structures, dsu, trees

Ants

2-sat, data structures, trees

Sonya and Ice Cream

binary search, data structures, dp, greedy, shortest paths, trees

Cycles in product

combinatorics, divide and conquer, trees

Two-Paths

data structures, dp, trees

We Need More Bosses

dfs and similar, graphs, trees

Cowmpany Cowmpensation

combinatorics, dp, math, trees

GCD Counting

divide and conquer, dp, dsu, number theory, trees

Flow Control

dfs and similar, dp, greedy, trees

Prince's Problem

brute force, data structures, math, number theory, trees

Useful Decomposition

implementation, trees

Shark

brute force, data structures, dsu, trees

Cut 'em all!

dfs and similar, dp, graphs, greedy, trees

NN country

binary search, data structures, trees

Kuro and GCD and XOR and SUM

binary search, bitmasks, brute force, data structures, dp, dsu, greedy, math, number theory, strings, trees

Kuro and Walking Route

dfs and similar, trees

Cactus to Tree

dp, graphs, trees