Dušan's Railway

divide and conquer, graphs, trees

Stock Exchange

binary search, flows, graphs

Journey

data structures, divide and conquer, graphs, trees

New Year and Snowy Grid

dfs and similar, dsu, graphs, interactive

JYPnation

graphs

Kuroni and Antihype

bitmasks, brute force, dp, dsu, graphs

Red-Blue Graph

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

Harder Satisfiability

2-sat, dfs and similar, graphs

Swiper, no swiping!

graphs, implementation

Fake bullions

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

Island Puzzle

dfs and similar, dsu, graphs, trees

Tree

fft, graphs, trees

Complete the Permutations

combinatorics, fft, graphs, math

Can Bash Save the Day?

data structures, divide and conquer, graphs, trees

Dynamic Shortest Path

graphs, shortest paths

Tanya is 5!

graph matchings, graphs, greedy, schedules

Hex Dyslexia

bitmasks, brute force, dp, graphs

Seollal

graphs

Kevin and Grid

fft, graphs, math

Finding satisfactory solutions

combinatorics, dp, graphs, greedy, math

One Billion Shades of Grey

flows, graphs

Gold Experience

constructive algorithms, graphs, math, number theory, probabilities

Harry Vs Voldemort

dfs and similar, dp, graphs, trees

Matvey's Birthday

bitmasks, graphs

Bear and Chemistry

data structures, dfs and similar, graphs, trees

Oppa Funcan Style Remastered

graphs, math, number theory, shortest paths

Public Service

constructive algorithms, graphs, trees

Roads Orientation Problem

graphs

Planar Perimeter

constructive algorithms, graphs

Special Edges

flows, graphs

Strange Permutation

binary search, combinatorics, data structures, dp, graphs, implementation, two pointers

Bimatching

graphs

Dirty Arkady's Kitchen

data structures, dp, graphs, shortest paths

New Year and Social Network

data structures, graph matchings, graphs, math, trees

Shifting Dominoes

data structures, geometry, graphs, trees

Pink Floyd

graphs, interactive

Invertation in Tournament

brute force, divide and conquer, graphs, math

Election Promises

games, graphs

ALT

data structures, flows, graphs, trees

New Year and Forgotten Tree

constructive algorithms, flows, graphs

Kyoya and Train

dp, fft, graphs, math, probabilities

Tourists

data structures, dfs and similar, graphs, trees

Distance Sum

graphs

Projectors

flows, graphs

Football

graphs

Perpetual Motion Machine

constructive algorithms, dp, graphs, implementation, math, trees

Cow and Exercise

flows, graphs, shortest paths

String Transformation 2

bitmasks, dp, graphs, trees

Flip and Reverse

data structures, graphs, greedy

Cycling City

dfs and similar, graphs

Unusual Graph

*special problem, graphs

Alpha planetary system

constructive algorithms, graphs, shortest paths

Nastya and Bees

graphs, interactive, probabilities

Spider

geometry, graphs

Gnomes of Might and Magic

data structures, graphs, implementation, shortest paths

Alice and the Cactus

dfs and similar, graphs, math, probabilities

Knightmare (hard)

graphs, interactive, shortest paths

Maximum Flow

flows, graphs

Privatization

flows, graphs

Planar Graph

flows, geometry, graphs

Wizards and Roads

data structures, divide and conquer, graph matchings, graphs, greedy

Mike and code of a permutation

constructive algorithms, data structures, graphs, sortings

James and the Chase

dfs and similar, graphs, probabilities, trees

Indecisive Taxi Fee

data structures, graphs, shortest paths

Graph Game

graphs

Coffee Varieties (hard version)

constructive algorithms, graphs, interactive

Abandoning Roads

brute force, dp, graphs, greedy

Points and Segments

graphs

The Classic Problem

data structures, graphs, shortest paths

Sergey's problem

constructive algorithms, graphs

Knightmare (easy)

graphs, interactive, shortest paths

Deja Vu

constructive algorithms, graphs, implementation

Restore the Tree

graphs, greedy, trees

Cactus to Tree

dp, graphs, trees

Take Metro

brute force, data structures, graphs

Shake It!

combinatorics, dp, flows, graphs

Almost Same Distance

dfs and similar, graphs

TOF

dfs and similar, graphs

Bear and Chase

brute force, dfs and similar, graphs, implementation, math, probabilities

Upgrading Cities

dfs and similar, graphs

Wizards and Bets

dfs and similar, graphs, math, matrices

Timofey and a flat tree

data structures, graphs, hashing, shortest paths, trees

Black Widow

dp, graphs, implementation, math

Shortest Path Queries

bitmasks, data structures, dsu, graphs

Pumping Stations

brute force, dfs and similar, divide and conquer, flows, graphs, greedy, trees

BubbleReactor

dp, graphs

Greedy Petya

*special problem, dfs and similar, graphs, greedy

The Overdosing Ubiquity

brute force, dfs and similar, graphs

Tree nesting

combinatorics, graphs, trees

Familiar Operations

brute force, graphs, math

Nikita and game

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

Directing Edges

dfs and similar, dp, graphs, trees

Coffee Varieties (easy version)

graphs, interactive

Tournament Construction

constructive algorithms, dp, graphs, greedy, math

Mister B and Flight to the Moon

constructive algorithms, graphs

Delivery Oligopoly

brute force, dp, graphs

Nezzar and Hidden Permutations

constructive algorithms, dfs and similar, graphs

Road Repairs

dfs and similar, graphs, greedy

Sherlock's bet to Moriarty

constructive algorithms, data structures, divide and conquer, geometry, graphs, implementation, trees

Big Problems for Organizers

data structures, graphs, trees