Balanced Unshuffle (Hard)

constructive algorithms, trees

Frequency Mismatch (Hard Version)

binary search, data structures, dfs and similar, hashing, probabilities, trees

My Beautiful Madness

data structures, trees

Min-Fund Prison (Medium)

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

Perpetual Motion Machine

constructive algorithms, dp, graphs, implementation, math, trees

Iron Man

data structures, geometry, trees

Train Tracks

data structures, trees

Send Tree to Charlie

combinatorics, dfs and similar, dsu, trees

Range Diameter Sum

data structures, trees

Ants

2-sat, data structures, trees

Mashtali vs AtCoder

games, trees

Santa's Gift

data structures, trees

Galaxy Union

dp, trees, two pointers

Furukawa Nagisa's Tree

binary search, divide and conquer, sortings, trees

Prefix Max Set Counting

data structures, dp, trees

Flower-like Pseudotree

constructive algorithms, graphs, greedy, implementation, trees

Two Subtrees

data structures, trees

Roads in E City

interactive, math, probabilities, trees

Ball-Stackable

constructive algorithms, data structures, dp, trees

Problem of offices

constructive algorithms, dfs and similar, dp, trees

Communism

bitmasks, dp, trees

Island Puzzle

dfs and similar, dsu, graphs, trees

Ember and Storm's Tree Game

combinatorics, dp, games, trees

Diverse Coloring

constructive algorithms, trees

Cheat and Win

bitmasks, data structures, games, trees

Tree

fft, graphs, trees

Evidence Board

*special problem, constructive algorithms, dfs and similar, graphs, trees

MEX Tree Manipulation

data structures, trees

Two Rooted Trees

data structures, implementation, trees

Harry Vs Voldemort

dfs and similar, dp, graphs, trees

Star Trek

*special problem, combinatorics, dfs and similar, dp, games, graphs, matrices, trees

Modernization of Treeland

*special problem, dfs and similar, trees

Thanos Snap

binary search, dp, games, greedy, trees

Journey

data structures, divide and conquer, graphs, trees

Euler tour

constructive algorithms, trees

Cactus to Tree

dp, graphs, trees

Baldman and the military

dfs and similar, graphs, trees

Imitating the Key Tree

combinatorics, dsu, trees

Iqea

data structures, dfs and similar, divide and conquer, dsu, shortest paths, trees

Tree and Permutation Game

dfs and similar, games, graphs, trees

ELCA

data structures, trees

Poachers

dp, games, graphs, trees

Tree LGM

constructive algorithms, divide and conquer, games, trees

Sloth

dfs and similar, dp, graph matchings, trees

Escaping on Beaveractor

data structures, implementation, trees

Tree and Table

dfs and similar, dp, implementation, trees

Moonwalk challenge

data structures, strings, trees

Trains and Airplanes

dfs and similar, graphs, shortest paths, trees

Build Railway Stations

*special problem, greedy, trees

New Year Running

number theory, trees

Alphabetic Tree

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

Min-Fund Prison (Hard)

bitmasks, dfs and similar, dp, graphs, trees

Strange device

binary search, interactive, math, trees

Restore the Tree

graphs, greedy, trees

Lost Nodes

constructive algorithms, dp, graphs, interactive, sortings, trees

Red Blue Tree

data structures, implementation, trees

Rap God

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

Optimizations From Chelsu

divide and conquer, dp, number theory, trees

Finding the Vertex

brute force, dfs and similar, dp, interactive, trees

Dušan's Railway

divide and conquer, graphs, trees

Tree Diameter

interactive, trees

Visible Black Areas

data structures, dsu, geometry, trees

LuoTianyi and Cartridge

data structures, trees

Upside Down

data structures, string suffix structures, strings, trees

Verifying Kingdom

binary search, divide and conquer, interactive, trees

Interactive Mex Tree

constructive algorithms, dfs and similar, interactive, trees

Clubstep

binary search, brute force, data structures, greedy, trees

Help King

implementation, probabilities, trees

Pisces

data structures, flows, trees

An easy problem about trees

dp, games, greedy, trees

Centroid Guess

interactive, probabilities, trees

Assigning Fares

dp, trees

Doremy's Swapping Trees

dfs and similar, graphs, trees

Tree of Life (medium)

constructive algorithms, hashing, trees

Standard Graph Problem

data structures, graphs, greedy, trees

Public Service

constructive algorithms, graphs, trees

Goldberg Machine 3

dp, trees

Spiderweb Trees

dp, geometry, trees

Redundant Routes

constructive algorithms, dp, trees

Doremy's Average Tree

data structures, dp, greedy, trees

King's Path

*special problem, math, trees

Farmer John's Favorite Intern

data structures, dp, flows, trees

Tree of Life (hard)

trees

Road Repair in Treeland

*special problem, binary search, dp, trees

Burenka and Pether

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