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

NN country

binary search, data structures, trees

Shark

brute force, data structures, dsu, trees

Cut 'em all!

dfs and similar, dp, graphs, greedy, trees

Useful Decomposition

implementation, trees

Cactus to Tree

dp, graphs, trees

The Number Games

data structures, greedy, 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

Short Code

data structures, dp, greedy, strings, trees

Destruction of a Tree

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

Visible Black Areas

data structures, dsu, geometry, trees

Simple Cycles Edges

dfs and similar, graphs, trees

Santa's Gift

data structures, trees

Alternating Tree

combinatorics, dfs and similar, divide and conquer, dp, probabilities, trees

Full Binary Tree Queries

brute force, implementation, trees

Mahmoud and Ehab and the wrong algorithm

constructive algorithms, trees

Maximum Control (medium)

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

Heaps

dp, trees

Iqea

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

Fafa and Ancient Mathematics

dfs and similar, dp, trees

Tree

binary search, dp, trees

Peculiar apple-tree

dfs and similar, graphs, trees

Autocompletion

*special problem, strings, trees

May Holidays

data structures, trees

Public Service

constructive algorithms, graphs, trees

Perfect Security

data structures, greedy, strings, trees

Upside Down

data structures, string suffix structures, strings, trees

Stranger Trees

dp, math, matrices, trees

Jamie and Tree

data structures, trees

Jamie and To-do List

data structures, interactive, trees

Imbalance Value of a Tree

data structures, dsu, graphs, trees

Ember and Storm's Tree Game

combinatorics, dp, games, trees

Palindromes in a Tree

bitmasks, data structures, divide and conquer, trees

Christmas Spruce

implementation, trees

Tree Destruction

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

Hashing Trees

constructive algorithms, trees

Ralph And His Tour in Binary Country

brute force, data structures, trees

Subtree Minimum Query

data structures, trees

Sloth

dfs and similar, dp, graph matchings, trees

Petya and Catacombs

dsu, greedy, implementation, trees

Danil and a Part-time Job

bitmasks, data structures, trees

Restore the Tree

graphs, greedy, trees

Points, Lines and Ready-made Titles

dfs and similar, dsu, graphs, trees

Policeman and a Tree

dp, graphs, trees

Cities Excursions

dfs and similar, graphs, trees

Mahmoud and Ehab and the bipartiteness

dfs and similar, graphs, trees

Arkady and a Nobody-men

data structures, dfs and similar, trees

Desk Disorder

combinatorics, dfs and similar, dsu, graphs, trees

Third Month Insanity

dp, probabilities, trees

Masha and Cactus

dp, trees

Similar Words

dp, hashing, strings, trees

Harry Vs Voldemort

dfs and similar, dp, graphs, trees

Rowena Ravenclaw's Diadem

trees

Helga Hufflepuff's Cup

dp, trees

Dating

brute force, dfs and similar, graphs, trees

Berland SU Computer Network

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

Chemistry in Berland

dfs and similar, greedy, trees

Upgrading Tree

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

Nikita and game

binary search, dfs and similar, divide and conquer, graphs, trees

Ilya And The Tree

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

In a Trap

trees

Journey

dfs and similar, dp, graphs, probabilities, trees

Diverging Directions

data structures, dfs and similar, trees

Roads in the Kingdom

dfs and similar, dp, graphs, trees

Red-Black Cobweb

data structures, divide and conquer, implementation, trees

Misha, Grisha and Underground

dfs and similar, graphs, trees

Perpetual Motion Machine

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

Singer House

combinatorics, dp, graphs, trees

Best Edge Weight

data structures, dfs and similar, graphs, trees

High Load

constructive algorithms, greedy, implementation, trees

Tree Queries

dfs and similar, graphs, trees

Madness

constructive algorithms, dfs and similar, trees

Okabe and Boxes

data structures, greedy, trees

MEX Queries

binary search, data structures, trees

Choosing The Commander

bitmasks, data structures, trees

Karen and Supermarket

brute force, dp, trees

An overnight dance in discotheque

dfs and similar, dp, geometry, greedy, trees

Sagheer and Apple Tree

games, trees

Sagheer and Kindergarten

dfs and similar, graphs, implementation, trees

Surprise me!

divide and conquer, math, number theory, trees

Expected diameter of a tree

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

Send the Fool Further! (hard)

dfs and similar, dp, math, trees

Send the Fool Further! (medium)

dp, trees

Send the Fool Further! (easy)

dfs and similar, graphs, trees

Police Stations

constructive algorithms, dfs and similar, dp, graphs, shortest paths, trees

Bank Hacking

constructive algorithms, data structures, dp, trees

Problem of offices

constructive algorithms, dfs and similar, dp, trees

Paths in a Complete Binary Tree

bitmasks, trees

ALT

data structures, flows, graphs, trees

Rap God

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

Andryusha and Colored Balloons

dfs and similar, graphs, greedy, trees

Peterson Polyglot

brute force, dfs and similar, dsu, hashing, strings, trees

Sherlock's bet to Moriarty

constructive algorithms, data structures, divide and conquer, geometry, graphs, implementation, trees

Verifying Kingdom

binary search, divide and conquer, interactive, trees

Bear and Tree Jumps

dfs and similar, dp, trees

Garland

dfs and similar, graphs, greedy, trees

Mahmoud and a xor trip

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