Division by Two and Permutation

constructive algorithms, flows, graph matchings, greedy, math

Gregor and the Pawn Game

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

Li Hua and Maze

constructive algorithms, flows, graphs, greedy, implementation

Qpwoeirut And The City

dp, flows, greedy, implementation

Engineer Artem

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

Chef Monocarp

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

Alyona and a Narrow Fridge

binary search, flows, greedy, sortings

Armchairs

dp, flows, graph matchings, greedy

Secret Santa

constructive algorithms, flows, graphs, greedy, math

Rock, Paper, Scissors

brute force, constructive algorithms, flows, greedy, math

Treasure Island

dfs and similar, dp, flows, hashing

Vasya And The Matrix

constructive algorithms, flows, math

Koxia and Game

constructive algorithms, data structures, dfs and similar, dsu, flows, games, graph matchings, graphs, implementation

Soldier and Traveling

flows, graphs, math

Array and Operations

flows, graph matchings, number theory

Single-use Stones

binary search, flows, greedy, two pointers

Vlad and Trouble at MIT

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

Ciel and Duel

dp, flows, greedy

Paired Payment

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

Segments Removal

data structures, dsu, flows, implementation, two pointers

Delivery Bears

binary search, flows, graphs

Fox And Dinner

flows

Little C Loves 3 II

brute force, constructive algorithms, flows, graph matchings

Gosha is hunting

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

Petya and Graph

flows, graphs

Olympiad in Programming and Sports

dp, flows, graphs, greedy

One-Way Reform

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

T-shirts Distribution

constructive algorithms, flows, greedy

Valuable Paper

binary search, flows, graph matchings, graphs

Yet Another Array Counting Problem

binary search, data structures, divide and conquer, dp, flows, math, trees

Maximize Mex

flows, graph matchings, graphs

Ann and Books

data structures, flows, hashing

Flawed Flow

constructive algorithms, flows, graphs, greedy

Build String

flows, graphs

Grouped Carriages

binary search, data structures, dp, flows, greedy

Four Points

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

Kirill and Company

bitmasks, brute force, dfs and similar, dp, flows, graphs, shortest paths

Goods transportation

dp, flows, greedy

Binary Tree on Plane

flows, trees

k-Maximum Subsequence Sum

data structures, flows, graphs, implementation

Almost Permutation

flows

Rectangle Painting 2

flows, graph matchings, graphs

April Fools' Problem (medium)

binary search, flows, graphs

Bricks

flows, graph matchings, graphs

Card Game

binary search, flows, graphs

Biologist

flows

The Most Reckless Defense

bitmasks, brute force, constructive algorithms, dp, flows, graph matchings, shortest paths

Summoning Minions

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

Double Sort II

dfs and similar, flows, graph matchings, graphs

Two Melodies

dp, flows

Exploration plan

binary search, flows, graph matchings, shortest paths

Anti-Palindromize

flows, graphs, greedy

Strange Set

flows, math

Matrix Problem

flows, graphs

Machine Programming

flows, graphs

Economic Difficulties

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

April Fools' Problem (hard)

binary search, data structures, flows

Buying Sets

flows, graph matchings

Petya and Pipes

flows, graphs, shortest paths

Zoning Restrictions

dp, flows, graphs

Captain America

flows, greedy

Allowed Letters

bitmasks, flows, graph matchings, graphs, greedy

Beautiful League

constructive algorithms, flows, graph matchings

Wine Factory (Hard Version)

data structures, dp, flows, greedy, matrices

Bear and Fair Set

flows, graphs

Vasya and Endless Credits

dp, flows, graph matchings, graphs, sortings

Button Lock

flows, graph matchings, graphs

Incorrect Flow

flows

Pumping Stations

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

Access Levels

bitmasks, dsu, flows, graph matchings

Alice and Recoloring 2

constructive algorithms, flows, graph matchings, greedy

Yet Another DAG Problem

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

Four Melodies

flows, graphs

Underfail

flows

Students Initiation

binary search, flows, graphs

Tidying Up

flows, graph matchings

ALT

data structures, flows, graphs, trees

Euclid Guess

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

New Year and Forgotten Tree

constructive algorithms, flows, graphs

Horseback Riding

flows, graphs

Road Construction

flows, graphs

The Doctor Meets Vader (Medium)

flows, graph matchings, graphs, shortest paths, sortings

Minimal k-covering

flows, graphs

Tidying Up

flows

Multiset of Strings

bitmasks, brute force, dp, fft, flows, graphs, math, meet-in-the-middle, trees

Privatization of Roads in Berland

flows, graph matchings, graphs

Heidi and Library (hard)

flows

Evacuation

flows, graphs, shortest paths

Bits of merry old England

flows, graphs

Madoka and The First Session

constructive algorithms, flows, graph matchings, graphs, implementation

Politics

flows, graphs

Yet Another Maxflow Problem

data structures, flows, graphs

Making It Bipartite

flows, graph matchings, graphs, number theory

Gang Up

flows, graphs

Cow and Exercise

flows, graphs, shortest paths

Bridge Club

flows, graph matchings, graphs, greedy

Red-Blue Graph

constructive algorithms, flows

Dominoes

combinatorics, flows, graph matchings, greedy

Starry Night Camping

constructive algorithms, flows, graphs

Fishermen

flows, graph matchings, greedy