4-point polyline

brute force, constructive algorithms, geometry, trees

Infinite Inversions

binary search, data structures, implementation, sortings, trees

Irrigation

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

Apple Tree

dfs and similar, number theory, trees

Fib-tree

brute force, dfs and similar, divide and conquer, number theory, trees

Information Graph

dfs and similar, dsu, graphs, trees

Tree Queries (Easy Version)

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

Happy Life in University

data structures, dfs and similar, greedy, trees

Maximum Weight Subset

dp, trees

Playoff Fixing

combinatorics, trees

New Year Tree

data structures, divide and conquer, trees

Tourists

data structures, dfs and similar, graphs, trees

An overnight dance in discotheque

dfs and similar, dp, geometry, greedy, trees

Construct the Binary Tree

brute force, constructive algorithms, trees

Hemose in ICPC ?

binary search, dfs and similar, implementation, interactive, math, number theory, trees

Moment of Bloom

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

Privatization of Roads in Treeland

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

Case of Computer Network

dfs and similar, graphs, trees

Weights Division (hard version)

binary search, dfs and similar, greedy, sortings, trees, two pointers

Removing Leaves

data structures, greedy, implementation, trees

Shark

brute force, data structures, dsu, trees

Running Track

dp, greedy, strings, trees

Ant on the Tree

constructive algorithms, dfs and similar, trees

Imbalance Value of a Tree

data structures, dsu, graphs, trees

Work Group

dfs and similar, dp, graphs, strings, trees

Neko and Aki's Prank

dp, greedy, trees

Mars rover

dfs and similar, graphs, implementation, trees

Qpwoeirut and Vertices

binary search, data structures, dfs and similar, divide and conquer, dsu, greedy, trees

Super M

dfs and similar, dp, graphs, trees

MEX Queries

binary search, data structures, trees

XOR Tree

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

Arpa’s letter-marked tree and Mehrdad’s Dokhtar-kosh paths

data structures, dfs and similar, trees

Guess Game

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

Karen and Supermarket

brute force, dp, trees

Jeremy Bearimy

dfs and similar, graphs, greedy, trees

LuoTianyi and the Floating Islands (Hard Version)

combinatorics, dfs and similar, math, probabilities, trees

Tree Array

brute force, combinatorics, dp, graphs, math, probabilities, trees

Dogeforces

constructive algorithms, data structures, dfs and similar, divide and conquer, dsu, greedy, sortings, trees

Trees of Tranquillity

data structures, dfs and similar, greedy, trees

Petya and Construction Set

constructive algorithms, graphs, math, sortings, trees

Paint the Tree

dp, sortings, trees

Mocha and Diana (Hard Version)

brute force, constructive algorithms, dfs and similar, dsu, graphs, greedy, trees, two pointers

Road Improvement

dp, trees

Tourism

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

Dungeons and Candies

dsu, graphs, greedy, trees

Hossam and (sub-)palindromic tree

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

Gold Transfer

binary search, data structures, dp, greedy, interactive, trees

Preorder

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

Kingdom and its Cities

dfs and similar, divide and conquer, dp, graphs, sortings, trees

Lynyrd Skynyrd

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

The Shortest Statement

graphs, shortest paths, trees

Berland Beauty

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

Tree Master

brute force, data structures, dfs and similar, trees

Array Collapse

data structures, divide and conquer, dp, trees

Choosing The Commander

bitmasks, data structures, trees

Destruction of a Tree

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

Potion Brewing Class

dfs and similar, math, number theory, trees

Bear and Tree Jumps

dfs and similar, dp, trees

Mahmoud and a xor trip

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

Sum Graph

brute force, constructive algorithms, graphs, implementation, interactive, shortest paths, trees

Treelabeling

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

How Many Paths?

dfs and similar, dp, graphs, trees

Beautiful Subarrays

data structures, divide and conquer, strings, trees

Unusual Entertainment

data structures, dfs and similar, dsu, shortest paths, sortings, trees, two pointers

Vlad and Trouble at MIT

dfs and similar, dp, flows, graphs, greedy, implementation, trees

Paths in a Complete Binary Tree

bitmasks, trees

Vlad and the Mountains

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

Bank Hacking

constructive algorithms, data structures, dp, trees

Sergey and Subway

dfs and similar, dp, trees

Centroids

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

Exposition

binary search, data structures, dsu, trees, two pointers

Build a Tree and That Is It

constructive algorithms, implementation, trees

New Year Santa Network

combinatorics, dfs and similar, graphs, trees

Generating Sets

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

Pillars

binary search, data structures, dp, sortings, trees

Count Paths

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

Timofey and Black-White Tree

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

Circular Spanning Tree

constructive algorithms, implementation, trees

Minimal Segment Cover

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

Lucky Tree

dp, dsu, trees

Score of a Tree

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

Kamil and Making a Stream

math, number theory, trees

Equal Tree Sums

constructive algorithms, dfs and similar, math, trees

Recovering BST

brute force, dp, math, number theory, trees

Two Chess Pieces

dfs and similar, dp, greedy, trees

Permutation Addicts

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

Sausage Maximization

bitmasks, data structures, trees

A Growing Tree

data structures, dfs and similar, trees

Puzzles

dfs and similar, math, probabilities, trees

Xor Tree

binary search, bitmasks, data structures, divide and conquer, dp, trees

Ilya And The Tree

dfs and similar, graphs, math, number theory, trees

High Load

constructive algorithms, greedy, implementation, trees

Game on Tree

implementation, math, probabilities, trees

Spiders

dp, greedy, trees

Weight the Tree

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

Edge Split

brute force, constructive algorithms, dfs and similar, dsu, graphs, probabilities, trees

Tree Construction

data structures, trees

Brain Network (medium)

dfs and similar, graphs, trees

01 Tree

constructive algorithms, data structures, dsu, greedy, sortings, trees

Misha, Grisha and Underground

dfs and similar, graphs, trees