Forced Online Queries Problem

data structures, divide and conquer, dsu, graphs, trees

Tiles Placement

constructive algorithms, dfs and similar, trees

Petya and Construction Set

constructive algorithms, graphs, math, sortings, trees

Path Queries

divide and conquer, dsu, graphs, sortings, trees

Road Repair in Treeland

*special problem, binary search, dp, trees

King's Path

*special problem, math, trees

Kamil and Making a Stream

math, number theory, trees

Koala and Notebook

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

Red Blue Tree

data structures, implementation, trees

Indie Album

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

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

Add on a Tree: Revolution

constructive algorithms, dfs and similar, implementation, trees

Add on a Tree

trees

Tree Painting

dfs and similar, dp, trees

Daleks' Invasion (hard)

data structures, dsu, graphs, trees

Daleks' Invasion (medium)

dfs and similar, graphs, shortest paths, trees

Daleks' Invasion (easy)

graphs, trees

Complete Mirror

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

Irrigation

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

Fedor Runs for President

data structures, dp, trees

Serge and Dining Room

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

Cover it!

dfs and similar, dsu, graphs, shortest paths, 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

Nauuo and Circle

combinatorics, dfs and similar, dp, 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

Serval and Rooted Tree

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

Neko and Aki's Prank

dp, greedy, trees

Tree Generator™

data structures, implementation, trees

Leaf Partition

dp, trees

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

Double Tree

data structures, divide and conquer, shortest paths, trees

Edgy Trees

dfs and similar, dsu, graphs, math, trees

Matches Are Not a Child's Play

data structures, trees

Greedy Subsequences

data structures, dp, trees

Legendary Tree

binary search, interactive, trees

Power Tree

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

Niyaz and Small Degrees

data structures, dp, 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

Tree-Tac-Toe

constructive algorithms, games, trees

Nearest Leaf

data structures, trees

Sasha and Algorithm of Silence's Sounds

data structures, trees

Sasha and Interesting Fact from Graph Theory

brute force, combinatorics, dp, math, 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

Tree with Maximum Cost

dfs and similar, dp, trees

Minimal Diameter Forest

constructive algorithms, dfs and similar, greedy, trees

Ehab and a weird weight formula

data structures, trees

Ehab and a component choosing problem

dp, greedy, math, trees

Minimum Diameter Tree

constructive algorithms, implementation, trees

Max Mex

data structures, trees

The Fair Nut and the Best Path

data structures, dp, trees

Speed Dial

dp, strings, trees

Vasya and a Tree

data structures, trees

Choosing Two Paths

dfs and similar, dp, greedy, trees

Random Forest Rank

dp, graph matchings, math, trees

Up and Down the Tree

dfs and similar, dp, trees

Company

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

Sergey and Subway

dfs and similar, dp, trees

Split the Tree

binary search, data structures, dp, greedy, trees

Bmail Computer Network

*special problem, dfs and similar, trees

Decorate Apple Tree

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

Tree and XOR

strings, trees

Euler tour

constructive algorithms, trees

The Shortest Statement

graphs, shortest paths, 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, graphs, trees

Intersecting Subtrees

dfs and similar, interactive, 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

Region Separation

combinatorics, dp, number theory, trees

Vasya and Maximum Matching

dp, 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

Dominant Indices

data structures, dsu, trees

Ants

2-sat, data structures, trees

Military Problem

dfs and similar, graphs, trees

Sonya and Ice Cream

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

Two-Paths

data structures, dp, trees

We Need More Bosses

dfs and similar, graphs, trees

Cycles in product

combinatorics, divide and conquer, trees