Police Stations

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

Civilization

dfs and similar, dp, dsu, ternary search, trees

Water Tree

data structures, dfs and similar, graphs, trees

Connected Components?

data structures, dfs and similar, dsu, graphs

Blood Cousins

binary search, data structures, dfs and similar, trees

A and B and Lecture Rooms

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

Ciel the Commander

constructive algorithms, dfs and similar, divide and conquer, greedy, trees

Minimum spanning tree for each edge

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

Tree Painting

dfs and similar, dp, trees

T-decomposition

dfs and similar, graphs, greedy, trees

Dominoes

dfs and similar, graphs

Sweets Game

bitmasks, dfs and similar, dp, games, implementation

General Mobilization

data structures, dfs and similar, sortings

Chocolate

dfs and similar, implementation

Circle of Numbers

brute force, dfs and similar, implementation

Dima and Trap Graph

binary search, data structures, dfs and similar, dsu, shortest paths, two pointers

Tree-String Problem

*special problem, dfs and similar, hashing, strings

Weak Memory

dfs and similar, dsu

Sereja and Periods

binary search, dfs and similar, strings

Wires

dfs and similar, graphs, greedy

Minimal Diameter Forest

constructive algorithms, dfs and similar, greedy, trees

Gifts by the List

constructive algorithms, dfs and similar, graphs, trees

Polycarp and Hay

dfs and similar, dsu, graphs, greedy, sortings

Giving Awards

dfs and similar

Dasha and Puzzle

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

An overnight dance in discotheque

dfs and similar, dp, geometry, greedy, trees

Infinite Maze

dfs and similar, graphs

Vitaly and Cycle

combinatorics, dfs and similar, graphs, math

Copy of a Copy of a Copy

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

Unusual Minesweeper

binary search, dfs and similar, dsu, greedy, sortings

Work Group

dfs and similar, dp, graphs, strings, trees

Berzerk

dfs and similar, dp, games

Ant on the Tree

constructive algorithms, dfs and similar, trees

Mars rover

dfs and similar, graphs, implementation, trees

Remove Directed Edges

dfs and similar, dp, graphs

Jeremy Bearimy

dfs and similar, graphs, greedy, trees

Cycle

dfs and similar, graphs

Destruction of a Tree

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

Lynyrd Skynyrd

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

Sergey and Subway

dfs and similar, dp, trees

Rudolf and Subway

constructive algorithms, dfs and similar, graphs, shortest paths

Gourmet choice

dfs and similar, dp, dsu, graphs, greedy

Nash Matrix

constructive algorithms, dfs and similar, graphs, implementation

Count Paths

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

Mahmoud and a Dictionary

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

A Growing Tree

data structures, dfs and similar, trees

Ilya And The Tree

dfs and similar, graphs, math, number theory, 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

Koxia and Game

constructive algorithms, data structures, dfs and similar, dsu, flows, games, graph matchings, graphs, implementation

Two Sets

2-sat, dfs and similar, dsu, graph matchings, greedy

Garland

dfs and similar, graphs, greedy, trees

Buds Re-hanging

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

Reverse

bitmasks, constructive algorithms, dfs and similar, implementation, math, strings

Orac and Game of Life

dfs and similar, graphs, implementation, shortest paths

Passable Paths (hard version)

data structures, dfs and similar, trees

The Strongest Build

binary search, brute force, data structures, dfs and similar, graphs, greedy, hashing, implementation

GCD Counting

data structures, dfs and similar, dp, number theory, trees

The Door Problem

2-sat, dfs and similar, dsu, graphs

1-Trees and Queries

data structures, dfs and similar, shortest paths, trees

Generate a String

dfs and similar, dp

Crazy Robot

dfs and similar, graphs

Appleman and Tree

dfs and similar, dp, trees

Three Paths on a Tree

dfs and similar, dp, greedy, trees

Choosing flowers

binary search, brute force, data structures, dfs and similar, dp, greedy, sortings, two pointers

Number of Simple Paths

combinatorics, dfs and similar, graphs, trees

Weights Division (easy version)

data structures, dfs and similar, greedy, trees

Monopole Magnets

constructive algorithms, dfs and similar, dsu, graphs

Book of Evil

dfs and similar, divide and conquer, dp, trees

Bertown roads

dfs and similar, graphs

Propagating tree

data structures, dfs and similar, trees

Captain Flint and Treasure

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

Reachability from the Capital

dfs and similar, graphs, greedy

Tree Shuffling

dfs and similar, dp, greedy, trees

Directing Edges

constructive algorithms, dfs and similar, graphs

Ice Cave

dfs and similar

Min-Fund Prison (Easy)

dfs and similar, trees

Game on Tree (Hard)

dfs and similar, dp, games, trees

Annual Ants' Gathering

dfs and similar, dp, greedy, trees

Solitaire

dfs and similar, dp

Orientation of Edges

dfs and similar, graphs

Paint it really, really dark gray

dfs and similar

Noise Level

dfs and similar, implementation, math

Intersecting Subtrees

dfs and similar, interactive, trees

Pairs of Numbers

brute force, dfs and similar, math, number theory

Data Center Maintenance

dfs and similar, graphs

Coprocessor

dfs and similar, dp, graphs, greedy

Chocolate

brute force, dfs and similar, math, meet-in-the-middle, number theory

Privatization of Roads in Treeland

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

Block Tower

constructive algorithms, dfs and similar, graphs

Connected Components

data structures, dfs and similar, dp, dsu

The Road to Berland is Paved With Good Intentions

2-sat, dfs and similar, dsu, graphs

Inna and Dima

dfs and similar, dp, graphs, implementation

Completely Searching for Inversions

dfs and similar, dp, graphs

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

New Year and Fireworks

brute force, data structures, dfs and similar, dp, implementation

New Year Santa Network

combinatorics, dfs and similar, graphs, trees

Generating Sets

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

Spanning Tree with One Fixed Degree

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