Caveman

combinatorics, graphs

Copper Squander

binary search, data structures, dsu, graphs, greedy, math, sortings, ternary search

XOR Problem

bitmasks, constructive algorithms, graphs, greedy, math

PLUSworld

constructive algorithms, graphs, greedy

Traveling the World

combinatorics, constructive algorithms, graphs, greedy, math

Come Be My Friend, Don't Be So Scared (Hard Version)

constructive algorithms, data structures, dsu, graphs, hashing, trees, two pointers

Edge Three-Coloring

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

Treasure Map Destruction (Counting Version)

dfs and similar, dp, dsu, graphs, math

Plus Minus Tree

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

Spying on the Beaver

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

4-beauty

bitmasks, dp, graphs, math, number theory

Diameter Intersections

brute force, dfs and similar, fft, graphs, implementation, trees

Even Simple Path

constructive algorithms, graphs, shortest paths

Construct an Array (Hard Version)

2-sat, constructive algorithms, dfs and similar, graphs, implementation

Fair and Square

combinatorics, dp, graphs, math, number theory, trees

The end of this world,

data structures, divide and conquer, dsu, graphs

Hunting the Beast

combinatorics, dp, graphs, math

Infinite Work

combinatorics, graphs, greedy, math, trees

Permutation Commutation

data structures, graphs, greedy

Shortest GCD Paths

dp, graphs, math, number theory, shortest paths, shortest paths

Deconstruction Tree

combinatorics, data structures, dp, graphs, trees

Simple Problem

brute force, graphs, greedy, number theory

Zhily and Cycle

graphs, greedy

Statistics on Tree

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

Building Tree

data structures, divide and conquer, dsu, graphs, graphs, implementation

Definitely Larger

binary search, constructive algorithms, data structures, graphs, greedy, sortings

Oriented Journey

bitmasks, brute force, communication, constructive algorithms, graphs, interactive, 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

Hanabi

binary search, data structures, dp, dsu, flows, graph matchings, graphs, greedy

Extra Transition

graphs

Simons and Reconstructing His Roads

constructive algorithms, constructive algorithms, constructive algorithms, constructive algorithms, data structures, data structures, dsu, graphs

Grid Path

dp, dp, graphs, matrices

Alternating Path

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

Indivisible

brute force, constructive algorithms, 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 and Queries

binary search, data structures, dp, graphs, trees

Parabola Independence

dp, graphs, greedy, math, sortings

The Turtle Strikes Back

dp, graphs, greedy, implementation

Remove the Grail Tree

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

Swap to Rearrange

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

Maximize Determinant

graphs

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

Knit the Grid

2-sat, constructive algorithms, graphs, matrices

Greta's Game

binary search, dp, graphs, greedy, math

Blackslex and Another RGB Walking

communication, constructive algorithms, graphs, interactive, number theory, trees

Numbers or Fireworks

bitmasks, combinatorics, dp, graphs

Create or Duplicate

bitmasks, graphs, number theory, shortest paths

Fibonacci Paths

data structures, dp, graphs, sortings

New Kingdom

constructive algorithms, graphs, implementation

Maximum Distance To Port

graphs, shortest paths

Cluster Computing System

graphs, greedy, math

Intercepting Butterflies

bitmasks, communication, constructive algorithms, graphs, interactive

Pointless Machine

constructive algorithms, graphs, interactive, trees

Chain Prefix Rank (Hard Version)

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

Journey

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

SubMST

combinatorics, graphs, trees

Distinct GCDs (Hard Version)

combinatorics, constructive algorithms, graphs, math, number theory, number theory

Distinct GCDs (Easy Version)

constructive algorithms, graphs, math, number theory

Sink

data structures, divide and conquer, dsu, graphs, implementation

Palindrome Flipping

brute force, constructive algorithms, graphs, implementation, shortest paths, strings

Best Time to Buy and Sell Stock

binary search, brute force, data structures, dp, games, graphs, greedy

Juan's Colorful Tree

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

Batteries

brute force, constructive algorithms, graph matchings, graphs, interactive, math

Abraham's Great Escape

constructive algorithms, graphs

Catshock

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

Monotone Subsequence

constructive algorithms, graphs, greedy, interactive, math

Cycle Closing

constructive algorithms, graphs, implementation, shortest paths, trees

Maxflow GCD Coloring

constructive algorithms, flows, graphs

Long Journey

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

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 (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

Flint and Steel

data structures, dp, graphs

The Nether

graphs, interactive

Rada and the Chamomile Valley

dfs and similar, graphs, shortest paths

Sea, You & copriMe

brute force, constructive algorithms, graphs, greedy, math, number theory

Arboris Contractio

data structures, graphs, greedy, trees

Induced Subgraph Queries

data structures, graphs, sortings

Double Perspective

constructive algorithms, dp, dsu, graphs, greedy, sortings

Strict Triangle

graphs, greedy, shortest paths

23 Rises Again

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

Inter Active (Hard Version)

binary search, bitmasks, constructive algorithms, graphs, implementation, interactive, math, probabilities

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

Traffic Lights

brute force, data structures, divide and conquer, dp, graphs, greedy, shortest paths

Eulerian Line Graph

graphs, greedy, math

Superb Graphs

2-sat, graphs

Shifts and Swaps

data structures, graphs, hashing, 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

Omg Graph

brute force, dsu, graphs, greedy, shortest paths, sortings

Gellyfish and Mayflower

dp, graphs

Gellyfish and Camellia Japonica

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

Two Arrays

constructive algorithms, dfs and similar, graphs, math