Rearrange

brute force, constructive algorithms, graphs, greedy, sortings

String Transformation 2

bitmasks, dp, graphs, trees

String Transformation 1

dsu, graphs, greedy, sortings, strings, trees, two pointers

Tree Modification

brute force, constructive algorithms, dfs and similar, graph matchings, graphs, trees

The Hidden Pair (Hard Version)

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

The Hidden Pair (Easy Version)

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

TediousLee

dp, graphs, greedy, math, trees

Shifting Dominoes

data structures, geometry, graphs, trees

Ski Accidents

constructive algorithms, graphs, greedy

Necklace Assembly

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

Jog Around The Graph

binary search, dp, geometry, graphs

Solve The Maze

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

Ehab's Last Corollary

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

James and the Chase

dfs and similar, graphs, probabilities, trees

Johnny and Megan's Necklace

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

Johnny and Contribution

constructive algorithms, graphs, greedy, sortings

Polygon

dp, graphs, implementation, shortest paths

Graph Coloring

dfs and similar, dp, graphs

Orac and Game of Life

dfs and similar, graphs, implementation, shortest paths

Phoenix and Memory

data structures, dfs and similar, graphs, greedy

Magic Tricks

*special problem, dp, graphs

Constructing the Dungeon

*special problem, graphs, greedy

Quantifier Question

dfs and similar, dp, graphs, math

Monopole Magnets

constructive algorithms, dfs and similar, dsu, graphs

Weights Distributing

brute force, graphs, greedy, shortest paths, sortings

Nastya and Bees

graphs, interactive, probabilities

Nastya and Time Machine

constructive algorithms, dfs and similar, graphs, trees

Nastya and Unexpected Guest

dfs and similar, dp, graphs, shortest paths

Nastya and Scoreboard

bitmasks, dp, graphs, greedy

JYPnation

graphs

Journey

data structures, divide and conquer, graphs, trees

Robots on a Grid

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

Divisor Paths

combinatorics, graphs, greedy, math, number theory

Minimum Euler Cycle

constructive algorithms, graphs, greedy, implementation

Challenges in school №41

brute force, constructive algorithms, games, graphs, greedy, implementation, sortings

Tree Queries

dfs and similar, graphs, trees

Carousel

constructive algorithms, dp, graphs, greedy, math

Infinite Path

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

Princesses and Princes

brute force, graphs, greedy

Ehab's Last Theorem

constructive algorithms, dfs and similar, graphs, greedy

Ehab's REAL Number Theory Problem

brute force, dfs and similar, graphs, number theory, shortest paths

Maximum White Subtree

dfs and similar, dp, graphs, trees

Instant Noodles

graphs, hashing, math, number theory

Navigation System

dfs and similar, graphs, shortest paths

Nash Matrix

constructive algorithms, dfs and similar, graphs, implementation

Tourism

dp, graphs, probabilities

Cow and Exercise

flows, graphs, shortest paths

Cow and Fields

binary search, data structures, dfs and similar, graphs, greedy, shortest paths, sortings

Kuroni and Antihype

bitmasks, brute force, dp, dsu, graphs

Shortest and Longest LIS

constructive algorithms, graphs, greedy, two pointers

Super Jaber

dfs and similar, graphs, implementation, shortest paths

Time to Run

constructive algorithms, graphs, implementation

Around the World

bitmasks, combinatorics, dfs and similar, dp, graphs, graphs, math, trees

String Coloring (easy version)

constructive algorithms, dp, graphs, greedy, sortings

Chaotic V.

dp, graphs, greedy, math, number theory, trees

Coffee Varieties (easy version)

graphs, interactive

Coffee Varieties (hard version)

constructive algorithms, graphs, interactive

Prefix Enlightenment

dfs and similar, dsu, graphs

Numbers on Tree

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

Delete a Segment

brute force, constructive algorithms, data structures, dp, graphs, sortings, trees, two pointers

Seollal

graphs

New Year and Social Network

data structures, graph matchings, graphs, math, trees

Christmas Trees

graphs, greedy, shortest paths

The Cake Is a Lie

constructive algorithms, data structures, dfs and similar, graphs

Jeremy Bearimy

dfs and similar, graphs, greedy, trees

Segment Tree

data structures, dsu, graphs, trees

Two Fairs

combinatorics, dfs and similar, dsu, graphs

Nearest Opposite Parity

dfs and similar, graphs, shortest paths

Subset with Zero Sum

constructive algorithms, dfs and similar, graphs, math

Invertation in Tournament

brute force, divide and conquer, graphs, math

Foolprüf Security

graphs

Red-Blue Graph

dp, graphs, math, matrices, meet-in-the-middle

Almost Same Distance

dfs and similar, graphs

Decreasing Debts

constructive algorithms, data structures, graphs, greedy, implementation, math, two pointers

Economic Difficulties

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

Secret Passwords

dfs and similar, dsu, graphs

Fridge Lockers

graphs, implementation

Cheap Robot

binary search, dsu, graphs, shortest paths, trees

Harmonious Graph

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

Road Construction

flows, graphs

Wires

dfs and similar, graphs, greedy

Projectors

flows, graphs

The Coronation

graphs, implementation

Shichikuji and Power Grid

dsu, graphs, greedy, shortest paths, trees

Paint the Tree

brute force, constructive algorithms, dp, graphs, implementation, trees

Planar Perimeter

constructive algorithms, graphs

Sum Balance

bitmasks, dfs and similar, dp, graphs

0-1 MST

dfs and similar, dsu, graphs, sortings

Football

graphs

Swiper, no swiping!

graphs, implementation

Catowice City

2-sat, dfs and similar, graph matchings, graphs

The Maximum Subtree

dfs and similar, dp, graphs, trees

Alice and the Cactus

dfs and similar, graphs, math, probabilities

Complete Tripartite

brute force, constructive algorithms, graphs, hashing, implementation

Arson In Berland Forest

binary search, graphs, graphs, shortest paths

Tourism

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

Alpha planetary system

constructive algorithms, graphs, shortest paths

Xor Spanning Tree

divide and conquer, fft, graphs

BubbleReactor

dp, graphs

Forced Online Queries Problem

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