Gregor and the Pawn Game

dfs and similar, dp, flows, graph matchings, graphs, greedy, implementation

Division by Two and Permutation

constructive algorithms, flows, graph matchings, greedy, math

Alyona and a Narrow Fridge

binary search, flows, greedy, sortings

Secret Santa

constructive algorithms, flows, graphs, greedy, math

Chef Monocarp

dp, flows, graph matchings, greedy, math, sortings

Armchairs

dp, flows, graph matchings, greedy

Rock, Paper, Scissors

brute force, constructive algorithms, flows, greedy, math

Vasya And The Matrix

constructive algorithms, flows, math

T-shirts Distribution

constructive algorithms, flows, greedy

Treasure Island

dfs and similar, dp, flows, hashing

Single-use Stones

binary search, flows, greedy, two pointers

Ciel and Duel

dp, flows, greedy

Valuable Paper

binary search, flows, graph matchings, graphs

Engineer Artem

2-sat, chinese remainder theorem, constructive algorithms, fft, flows

Segments Removal

data structures, dsu, flows, implementation, two pointers

Build String

flows, graphs

Olympiad in Programming and Sports

dp, flows, graphs, greedy

Soldier and Traveling

flows, graphs, math

Array and Operations

flows, graph matchings, number theory

Flawed Flow

constructive algorithms, flows, graphs, greedy

Exploration plan

binary search, flows, graph matchings, shortest paths

Paired Payment

binary search, brute force, constructive algorithms, dp, flows, graphs, shortest paths

Little C Loves 3 II

brute force, constructive algorithms, flows, graph matchings

Delivery Bears

binary search, flows, graphs

One-Way Reform

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

Almost Permutation

flows

Tidying Up

flows

The Doctor Meets Vader (Medium)

flows, graph matchings, graphs, shortest paths, sortings

Fox And Dinner

flows

Ann and Books

data structures, flows, hashing

Biologist

flows

Petya and Pipes

flows, graphs, shortest paths

Tidying Up

flows, graph matchings

Road Construction

flows, graphs

Horseback Riding

flows, graphs

Evacuation

flows, graphs, shortest paths

Deciphering

flows, graph matchings

Petya and Graph

flows, graphs

Four Points

brute force, constructive algorithms, flows, geometry, greedy, implementation, math, ternary search

Maximize Mex

flows, graph matchings, graphs

Binary Tree on Plane

flows, trees

Machine Programming

flows, graphs

Economic Difficulties

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

Card Game

binary search, flows, graphs

April Fools' Problem (medium)

binary search, flows, graphs

Allowed Letters

bitmasks, flows, graph matchings, graphs, greedy

Underfail

flows

Students Initiation

binary search, flows, graphs

Privatization of Roads in Berland

flows, graph matchings, graphs

Cactusophobia

dfs and similar, flows

Summoning Minions

constructive algorithms, dp, flows, graph matchings, greedy, sortings

Rectangle Painting 2

flows, graph matchings, graphs

Anti-Palindromize

flows, graphs, greedy

Bear and Fair Set

flows, graphs

Minimal k-covering

flows, graphs

Gang Up

flows, graphs

Last chance

data structures, flows, graph matchings, graphs, trees

Two Melodies

dp, flows

Vasya and Endless Credits

dp, flows, graph matchings, graphs, sortings

Button Lock

flows, graph matchings, graphs

Four Melodies

flows, graphs

Yet Another DAG Problem

bitmasks, dfs and similar, dp, flows, graphs, math

Politics

flows, graphs

Heidi and Library (hard)

flows

Strange Set

flows, math

Zoning Restrictions

dp, flows, graphs

Beautiful League

constructive algorithms, flows, graph matchings

Bits of merry old England

flows, graphs

Yet Another Maxflow Problem

data structures, flows, graphs

Electric Scheme

flows, graph matchings

Scaygerboss

flows

World Evil

dp, flows

The Doctor Meets Vader (Hard)

flows, shortest paths

k-Maximum Subsequence Sum

data structures, flows, graphs, implementation

Bricks

flows, graph matchings, graphs

Alice and Recoloring 2

constructive algorithms, flows, graph matchings, greedy

Bridge Club

flows, graph matchings, graphs, greedy

Euclid Guess

constructive algorithms, flows, graph matchings, math, number theory

Goblins And Gnomes

brute force, dp, flows, graph matchings

Scaygerboss

flows

Goods transportation

dp, flows, greedy

Buying Sets

flows, graph matchings

Incorrect Flow

flows

Pumping Stations

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

April Fools' Problem (hard)

binary search, data structures, flows

Nanami's Power Plant

flows

Red-Blue Graph

constructive algorithms, flows

Shake It!

combinatorics, dp, flows, graphs

Chess Championship

constructive algorithms, flows, greedy, math

Pills

brute force, flows

Gosha is hunting

brute force, data structures, dp, flows, math, probabilities, sortings

Reindeer Games

binary search, constructive algorithms, data structures, divide and conquer, flows, graphs, shortest paths

Privatization

flows, graphs

Planar Graph

flows, geometry, graphs

Maximum Flow

flows, graphs

Flow Optimality

constructive algorithms, flows, math

Captain America

flows, greedy

Cow and Exercise

flows, graphs, shortest paths

Projectors

flows, graphs

Parametric Circulation

binary search, flows