Xor-Subsequence (hard version)

bitmasks, data structures, dp, strings, trees

Tree Compass

constructive algorithms, dfs and similar, greedy, trees

Make It Connected

binary search, brute force, constructive algorithms, dsu, graphs, greedy, matrices, trees, two pointers

GCD Counting

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

Gifts by the List

constructive algorithms, dfs and similar, graphs, trees

Big Maximum Sum

data structures, dp, greedy, implementation, math, trees

Company

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

Yet Another Array Counting Problem

binary search, data structures, divide and conquer, dp, flows, math, trees

Towers

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

Hamiltonian Spanning Tree

dfs and similar, dp, graph matchings, greedy, trees

The Maximum Subtree

dfs and similar, dp, graphs, trees

Edge Reverse

binary search, dfs and similar, graphs, trees

Kuro and GCD and XOR and SUM

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

Phoenix and Earthquake

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

Full Binary Tree Queries

brute force, implementation, trees

Nearest Leaf

data structures, trees

Hemose on the Tree

bitmasks, constructive algorithms, dfs and similar, trees

Delete a Segment

brute force, constructive algorithms, data structures, dp, graphs, sortings, trees, two pointers

IT Restaurants

dfs and similar, dp, trees

Subtree Minimum Query

data structures, trees

Light Bulbs (Easy Version)

brute force, combinatorics, dfs and similar, dp, dsu, graphs, math, trees

You Are Given a Tree

data structures, dp, trees

Tree

binary search, dp, trees

Desk Disorder

combinatorics, dfs and similar, dsu, graphs, trees

DIY Garland

constructive algorithms, greedy, trees

Tree Modification

brute force, constructive algorithms, dfs and similar, graph matchings, graphs, trees

Minimal Diameter Forest

constructive algorithms, dfs and similar, greedy, trees

Sasha and the Wedding Binary Search Tree

brute force, combinatorics, data structures, dfs and similar, math, trees

Beard Graph

data structures, dsu, trees

Cheap Robot

binary search, dsu, graphs, shortest paths, trees

Invariance of Tree

constructive algorithms, dfs and similar, greedy, trees

PermutationForces II

brute force, combinatorics, greedy, sortings, trees, two pointers

Daleks' Invasion (easy)

graphs, trees

Tree Destruction

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

Jamie and Tree

data structures, trees

Treeland Tour

data structures, dfs and similar, dp, trees

Intersecting Subtrees

dfs and similar, interactive, trees

Little Girl and Problem on Trees

data structures, graphs, trees

Cactus

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

Scheme

dfs and similar, graphs, trees

Unique Occurrences

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

On Changing Tree

data structures, graphs, trees

e-Government

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

There Should Be a Lot of Maximums

brute force, data structures, dfs and similar, dp, trees, two pointers

WTF?

*special problem, graph matchings, implementation, trees

Black and White Tree

dfs and similar, greedy, trees

Demiurges Play Again

dfs and similar, dp, math, trees

Old Berland Language

data structures, greedy, trees

Road Improvement

*special problem, dfs and similar, graphs, greedy, trees

Sasha and the Happy Tree Cutting

bitmasks, brute force, dfs and similar, dp, graphs, greedy, math, trees

Omsk Metro (hard version)

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

Spanning Tree Queries

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

Rubik's Cube Coloring (hard version)

brute force, dp, implementation, math, trees

Gift

dsu, graphs, sortings, trees

Plan of Lectures

constructive algorithms, dfs and similar, dsu, graphs, implementation, sortings, trees

Ehab and the Big Finale

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

Pairs of Pairs

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

Complete the MST

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

Ehab and a component choosing problem

dp, greedy, math, trees

Purple Crayon

data structures, dfs and similar, games, graphs, greedy, math, sortings, trees

The Fox and the Complete Tree Traversal

constructive algorithms, dp, implementation, math, trees

Caisa and Tree

brute force, dfs and similar, math, number theory, trees

DFS Trees

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

Palindromes in a Tree

bitmasks, data structures, divide and conquer, trees

Bear and Forgotten Tree 2

dfs and similar, dsu, graphs, trees

The Hidden Pair (Easy Version)

binary search, dfs and similar, graphs, interactive, shortest paths, trees

Split the Tree

binary search, data structures, dp, greedy, trees

Compressed Tree

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

Distinctive Roots in a Tree

data structures, dfs and similar, dp, trees

Short Code

data structures, dp, greedy, strings, trees

Black and White Tree

constructive algorithms, dsu, graphs, greedy, trees

New Roads

constructive algorithms, graphs, trees

Village (Minimum)

*special problem, dp, greedy, trees

PermuTree (hard version)

bitmasks, dfs and similar, dp, fft, greedy, implementation, math, trees

Koxia and Tree

combinatorics, dfs and similar, dp, dsu, math, probabilities, trees

Job Lookup

constructive algorithms, dp, shortest paths, trees

Sasha and Interesting Fact from Graph Theory

brute force, combinatorics, dp, math, trees

Close Vertices

data structures, divide and conquer, trees

Power Tree

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

Expected diameter of a tree

binary search, brute force, dfs and similar, dp, sortings, trees

Tree Folding

dfs and similar, dp, greedy, implementation, trees

Diameter Cuts

combinatorics, dfs and similar, dp, trees

Rollbacks (Easy Version)

brute force, data structures, dfs and similar, trees

LuoTianyi and XOR-Tree

data structures, dfs and similar, dp, dsu, greedy, trees

Tenzing and Tree

dfs and similar, greedy, shortest paths, sortings, trees

Leaf Sets

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

Binary Tree on Plane

flows, trees

The Hidden Pair (Hard Version)

binary search, dfs and similar, graphs, interactive, shortest paths, trees

Drazil and Morning Exercise

dfs and similar, dp, dsu, trees, two pointers

Xorcerer's Stones

bitmasks, constructive algorithms, dp, trees

Move and Swap

dfs and similar, dp, greedy, trees

Simple Cycles Edges

dfs and similar, graphs, trees

BFS Trees

combinatorics, dfs and similar, graphs, math, shortest paths, trees

Interactive Game with Coloring

brute force, constructive algorithms, dfs and similar, graphs, implementation, interactive, trees

Happy Tree Party

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

Tree Generator™

data structures, implementation, trees

Pastoral Oddities

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

Connectivity Addicts

constructive algorithms, dsu, graphs, greedy, interactive, shortest paths, trees

Tree Queries

dfs and similar, graphs, trees

Up and Down the Tree

dfs and similar, dp, trees