Stock Exchange

binary search, flows, graphs

Pisces

data structures, flows, trees

Parametric Circulation

binary search, flows

Flow Optimality

constructive algorithms, flows, math

Projectors

flows, graphs

April Fools' Problem (hard)

binary search, data structures, flows

ALT

data structures, flows, graphs, trees

Pills

brute force, flows

Oleg and chess

data structures, divide and conquer, flows, graph matchings

Planar Graph

flows, geometry, graphs

New Year and Forgotten Tree

constructive algorithms, flows, graphs

Captain America

flows, greedy

Maximum Flow

flows, graphs

Red-Blue Graph

constructive algorithms, flows

Shake It!

combinatorics, dp, flows, graphs

Scaygerboss

flows

Incorrect Flow

flows

Biologist

flows

Goods transportation

dp, flows, greedy

Gosha is hunting

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

Chess Championship

constructive algorithms, flows, greedy, math

Last chance

data structures, flows, graph matchings, trees

Scaygerboss

flows

Nanami's Power Plant

flows

Politics

flows, graphs

Pumping Stations

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

k-Maximum Subsequence Sum

data structures, flows, graphs, implementation

Fox And Dinner

flows

Privatization

flows, graphs

The Doctor Meets Vader (Hard)

flows, shortest paths

World Evil

dp, flows

Four Melodies

flows, graphs

Beautiful League

constructive algorithms, flows, graph matchings

Heidi and Library (hard)

flows

Yet Another Maxflow Problem

data structures, flows, graphs

Buying Sets

flows, graph matchings

Vasya and Endless Credits

dp, flows, graph matchings, graphs, sortings

Petya and Pipes

flows, graphs, shortest paths

Two Melodies

dp, flows

Electric Scheme

flows, graph matchings

Gang Up

flows, graphs

Bits of merry old England

flows, graphs

Privatization of Roads in Berland

flows, graphs

Road Construction

flows, graphs

Zoning Restrictions

dp, flows, graphs

April Fools' Problem (medium)

binary search, flows, graphs

Minimal k-covering

flows, graphs

Evacuation

flows, graphs, shortest paths

Bear and Fair Set

flows

Allowed Letters

bitmasks, flows, graph matchings, graphs, greedy

Anti-Palindromize

flows, graphs, greedy

Card Game

binary search, flows, graphs

Economic Difficulties

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

Rectangle Painting 2

flows, graph matchings, graphs

Ann and Books

data structures, flows, hashing

Flawed Flow

constructive algorithms, flows, graphs, greedy

Deciphering

flows, graph matchings

Students Initiation

binary search, flows

Underfail

flows

Exploration plan

binary search, flows, graph matchings, shortest paths

Machine Programming

flows, graphs

Binary Tree on Plane

flows, trees

Petya and Graph

flows, graphs

Maximize Mex

flows, graph matchings, graphs

Array and Operations

flows, graph matchings, number theory

Cactusophobia

dfs and similar, flows

The Doctor Meets Vader (Medium)

flows, graph matchings, graphs, shortest paths, sortings

Tidying Up

flows, graph matchings

Almost Permutation

flows

One-Way Reform

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

Soldier and Traveling

flows, graphs, math

Tidying Up

flows

Olympiad in Programming and Sports

dp, flows, greedy

Build String

flows, graphs

Segments Removal

data structures, dsu, flows, implementation, two pointers

Delivery Bears

binary search, flows, graphs

Little C Loves 3 II

brute force, constructive algorithms, flows, graph matchings

Ciel and Duel

dp, flows, greedy

Single-use Stones

binary search, flows, greedy, two pointers

T-shirts Distribution

constructive algorithms, flows, greedy

Vasya And The Matrix

constructive algorithms, flows, math

Treasure Island

dfs and similar, dp, flows, hashing

Alyona and a Narrow Fridge

binary search, flows, greedy, sortings