Fallen Leaves

dfs and similar, dp, dp, trees, trees

Statistics on Tree

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

Coloring a Red Black Tree

dfs and similar, dp, greedy, math, probabilities, trees, trees

Closer

dfs and similar, dp, trees

Tree Orientation (Hard Version)

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

Tree Orientation (Easy Version)

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

Toothless

constructive algorithms, dfs and similar, dsu

Boxed Like a Fish

dfs and similar, dp, games, shortest paths, trees

Upside Down Dijkstra

dfs and similar

Alternating Path

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

Interactive Graph (Hard Version)

combinatorics, dfs and similar, dp, graphs, interactive

Interactive Graph (Simple Version)

binary search, combinatorics, dfs and similar, dp, graphs, interactive

Idiot First Search

dfs and similar, dp, trees

Again Trees... (hard version)

bitmasks, data structures, dfs and similar, dp, fft, trees

Again Trees... (Easy Version)

bitmasks, dfs and similar, dp, trees

Remove the Grail Tree

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

Paths in a Tree

dfs and similar, interactive, sortings, trees

Swap to Rearrange

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

Zhora the Vacuum Cleaner

data structures, dfs and similar, dp, greedy, implementation, sortings, trees

Jerry and Tom

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

Cherry Tree

dfs and similar, dp, graphs, trees

Huge Pile

binary search, dfs and similar, dp, graphs, math

Jumping Man

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

Tree Coloring (Hard Version)

combinatorics, constructive algorithms, data structures, dfs and similar, greedy, implementation, trees

Tree Coloring (Easy Version)

constructive algorithms, dfs and similar, greedy, trees

Short Garland

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

Remove at the lowest cost

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

Game of Scientists (Version 2)

binary search, chinese remainder theorem, dfs and similar, interactive, math

Tree, TREE!!!

dfs and similar, dp, math, trees

Chain Prefix Rank (Hard Version)

binary search, combinatorics, data structures, dfs and similar, dp, graphs, math, trees

Chain Prefix Rank (Easy Version)

combinatorics, dfs and similar, dp, math, trees

Journey

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

Keygen 3

brute force, combinatorics, constructive algorithms, dfs and similar, math

Isaac's Queries

bitmasks, brute force, constructive algorithms, dfs and similar, divide and conquer, dp, greedy, interactive, math, probabilities

Juan's Colorful Tree

data structures, dfs and similar, dfs and similar, dsu, graphs, graphs, meet-in-the-middle, trees

Catshock

constructive algorithms, dfs and similar, graphs, trees, two pointers

Victorious Coloring (Easy Version)

dfs and similar, dp, greedy

Long Journey

dfs and similar, divide and conquer, dp, graphs, greedy, math, matrices, number theory

Inversion Value of a Permutation

constructive algorithms, dfs and similar, dp

Max Tree

constructive algorithms, dfs and similar, graphs, greedy

Merging Vertices in a Graph

*special problem, dfs and similar, dsu, graphs

Maple and Tree Beauty (Hard Version)

bitmasks, brute force, dfs and similar, dp, fft, trees

Maple and Tree Beauty (Easy Version)

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

Cry Me a River

dfs and similar, dp, games, graphs

By the Assignment

binary search, bitmasks, combinatorics, dfs and similar, dsu, graphs, math

Sliding Tree

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

I Yearned For The Mines

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

Rada and the Chamomile Valley

dfs and similar, graphs, shortest paths

Wafu!

bitmasks, brute force, data structures, dfs and similar, dp, math

23 Rises Again

brute force, dfs and similar, dp, flows, graph matchings, graphs, greedy, implementation, probabilities, trees

Ancient Tree

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

Root was Built by Love, Broken by Destiny

combinatorics, dfs and similar, graphs, trees

1-1-1, Free Tree!

brute force, data structures, dfs and similar, graphs, implementation, trees

Volcanic Eruptions

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

Red Light, Green Light (Hard version)

binary search, brute force, data structures, dfs and similar, dp, graphs, implementation, math, number theory

Red Light, Green Light (Easy version)

brute force, dfs and similar, dp, graphs, implementation, number theory

Wildflower

combinatorics, dfs and similar, trees

Gellyfish and Camellia Japonica

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

Small Operations

binary search, brute force, dfs and similar, dp, math, number theory, sortings

Kirei Attacks the Estate

dfs and similar, dp, greedy, trees

Two Arrays

constructive algorithms, dfs and similar, graphs, math

From Kazan with Love

dfs and similar, graphs, implementation, trees

Tree Colorings

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

Reachability and Tree

constructive algorithms, dfs and similar, graphs, trees

Melody

dfs and similar, graphs, implementation

Fewer Batteries

binary search, dfs and similar, dp, graphs, greedy, hashing

Penguin Steps

binary search, dfs and similar, flows, graphs, shortest paths

D/D/D

dfs and similar, graphs, greedy, shortest paths

Spruce Dispute

constructive algorithms, dfs and similar, graphs, greedy, implementation, shortest paths, trees

Apple Tree Traversing

brute force, dfs and similar, greedy, implementation, trees

Baudelaire (hard version)

binary search, dfs and similar, divide and conquer, implementation, interactive, trees

Goblin

dfs and similar, dp, dsu, greedy, math

Numbers and Strings

binary search, brute force, dfs and similar, dp, implementation, math

Local Construction

constructive algorithms, dfs and similar, implementation, two pointers

Clearing the Snowdrift

data structures, dfs and similar, dp, greedy

Baggage Claim

combinatorics, dfs and similar, dp, dsu, graphs, implementation, math, trees

Shorten the Array

binary search, bitmasks, data structures, dfs and similar, greedy, strings, trees, two pointers

Zebra-like Numbers

bitmasks, brute force, constructive algorithms, dfs and similar, dp, greedy, math

Disappearing Permutation

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

RGB Walking

bitmasks, chinese remainder theorem, dfs and similar, graphs, number theory

Trapmigiano Reggiano

constructive algorithms, data structures, dfs and similar, dp, greedy, sortings, trees

Tree Jumps

dfs and similar, dp, trees

Graph Inclusion

data structures, dfs and similar, divide and conquer, dsu, graphs

Porto Vs. Benfica

data structures, dfs and similar, dsu, graphs, shortest paths

Devyatkino

brute force, dfs and similar, greedy, math

Skibidus and Slay

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

Counting Is Not Fun (Hard Version)

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

Counting Is Not Fun (Easy Version)

combinatorics, data structures, dfs and similar, dp, dsu, graphs, hashing, implementation, math, trees

Triangle Tree

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

Remove Exactly Two

brute force, data structures, dfs and similar, dp, graphs, greedy, sortings, trees

The Game (Hard Version)

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

The Game (Easy Version)

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

Balanced Tree

dfs and similar, dp, graphs, greedy, trees

Graph Composition

dfs and similar, dsu, graphs, greedy

Secret Message

constructive algorithms, dfs and similar, math

Another Exercise on Graphs (hard version)

binary search, dfs and similar, dp, dsu, graphs, shortest paths, sortings

Nested Segments

combinatorics, dfs and similar, dp, dsu, math

Find the Permutation

brute force, dfs and similar, graphs, implementation, sortings

Resourceful Caterpillar Sequence

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

Tree Destruction

dfs and similar, dp, trees