Fairy

dfs and similar, divide and conquer, dsu

Ice cream coloring

constructive algorithms, dfs and similar, greedy

Berland and the Shortest Paths

brute force, dfs and similar, graphs, shortest paths

Cactus Wall

constructive algorithms, dfs and similar, graphs, shortest paths

Egor in the Republic of Dagestan

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

Fair Share

constructive algorithms, data structures, dfs and similar, graph matchings, graphs

Graph Transpositions

dfs and similar, graphs, greedy, shortest paths

Square Root of Permutation

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

Invariance of Tree

constructive algorithms, dfs and similar, greedy, trees

Little Pony and Summer Sun Celebration

constructive algorithms, dfs and similar, graphs

EKG

dfs and similar, dp

Tree Destruction

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

Treeland Tour

data structures, dfs and similar, dp, trees

Scheme

dfs and similar, graphs, trees

Wires

dfs and similar, graphs, greedy

Intersecting Subtrees

dfs and similar, interactive, trees

Unique Occurrences

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

Cactus

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

Prefix Enlightenment

dfs and similar, dsu, graphs

Vladik and Favorite Game

constructive algorithms, dfs and similar, graphs, interactive

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

Black and White Tree

dfs and similar, greedy, trees

Sasha and the Happy Tree Cutting

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

Session in BSU

binary search, dfs and similar, dsu, graph matchings, graphs

Noise Level

dfs and similar, implementation, math

Demiurges Play Again

dfs and similar, dp, math, trees

Shortest Path Problem?

dfs and similar, graphs, math

Vlad and Avoiding X

bitmasks, brute force, dfs and similar, dp, implementation

Road Improvement

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

Prime Gift

binary search, dfs and similar, math, meet-in-the-middle, number theory, two pointers

Looksery Party

constructive algorithms, dfs and similar, graphs, greedy

Wizard's Tour

constructive algorithms, dfs and similar, graphs

Omsk Metro (hard version)

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

Sum Balance

bitmasks, dfs and similar, dp, graphs

AND-MEX Walk

bitmasks, brute force, constructive algorithms, dfs and similar, dsu, graphs

Team-Building

data structures, dfs and similar, dsu, graphs

Spanning Tree Queries

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

Infinite Card Game

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

Plan of Lectures

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

Sereja and Periods

binary search, dfs and similar, strings

Divisors

brute force, dfs and similar, implementation, number theory

Graph Coloring

dfs and similar, graphs

Pairs of Pairs

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

Paint it really, really dark gray

dfs and similar

Complete the MST

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

Kirill and Company

bitmasks, brute force, dfs and similar, dp, flows, graphs, shortest paths

Purple Crayon

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

Knapsack

dfs and similar, dp, greedy

DFS Trees

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

Caisa and Tree

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

Johnny and Megan's Necklace

binary search, bitmasks, constructive algorithms, dfs and similar, dsu, graphs

Orientation of Edges

dfs and similar, graphs

Bear and Forgotten Tree 2

dfs and similar, dsu, graphs, trees

Compressed Tree

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

The Hidden Pair (Easy Version)

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

Routing

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

EKG

brute force, dfs and similar

Okabe and City

dfs and similar, graphs, shortest paths

Solitaire

dfs and similar, dp

Graph Cutting

dfs and similar, graphs

Distinctive Roots in a Tree

data structures, dfs and similar, dp, trees

Columns Swaps

2-sat, dfs and similar, dsu, graphs, implementation

Network Safety

dfs and similar, dsu, graphs, math, sortings

PermuTree (hard version)

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

Fast Travel Text Editor

data structures, dfs and similar, graphs, shortest paths

Divisors and Table

brute force, dfs and similar, dp, number theory

Weak Memory

dfs and similar, dsu

Koxia and Tree

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

Tree-String Problem

*special problem, dfs and similar, hashing, strings

Three Pieces

dfs and similar, dp, shortest paths

Circular Maze

brute force, dfs and similar, graphs, implementation

Dima and Trap Graph

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

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

LuoTianyi and XOR-Tree

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

Rollbacks (Easy Version)

brute force, data structures, dfs and similar, trees

Diameter Cuts

combinatorics, dfs and similar, dp, trees

The Hidden Pair (Hard Version)

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

Tree Folding

dfs and similar, dp, greedy, implementation, trees

Tenzing and Tree

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

Leaf Sets

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

Light Bulbs (Hard Version)

combinatorics, data structures, dfs and similar, dp, graphs, hashing

Drazil and Morning Exercise

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

Simple Cycles Edges

dfs and similar, graphs, trees

Break Up

dfs and similar, graphs

Move and Swap

dfs and similar, dp, greedy, trees

Jordan Smiley

*special problem, dfs and similar, geometry, implementation

Annual Ants' Gathering

dfs and similar, dp, greedy, trees

Falling Sand (Easy Version)

dfs and similar, graphs, greedy

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

You

dfs and similar, dp, math, number theory

Happy Tree Party

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

Almost Fault-Tolerant Database

brute force, constructive algorithms, dfs and similar, greedy, implementation

Decreasing Game

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

City Union

constructive algorithms, dfs and similar, dsu, geometry, greedy, implementation, math

ANDfinity

bitmasks, brute force, constructive algorithms, dfs and similar, dsu, graphs

Add on a Tree: Revolution

constructive algorithms, dfs and similar, implementation, trees

Disks

dfs and similar, geometry, graph matchings, graphs