Red-White Fence

combinatorics, fft

Hobbits

binary search, geometry

XOR, Tree, and Queries

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

Tick, Tock

combinatorics, dfs and similar, dsu, graphs

Putting Boxes Together

data structures

Nobody is needed

2-sat, data structures, dfs and similar, dp

Board Game

data structures, dfs and similar

Caterpillar on a Tree

dfs and similar, graphs, greedy, implementation, sortings, trees

Marbles

hashing, strings

Brukhovich and Exams

brute force, greedy, implementation, math, sortings

Zeros and Ones

bitmasks, divide and conquer, dp, math

Serval and Music Game

brute force, dp, implementation, math, number theory

Codeword

combinatorics, strings

Library game

games, greedy, interactive, sortings

Cowslip Collections

combinatorics, math, number theory

Connecting Vertices

dp, graphs

DZY Loves Strings

binary search, hashing, strings, two pointers

Game

math

Smile House

binary search, graphs, matrices

Laboratory on Pluto

constructive algorithms, dp, greedy, math

Bear and Fair Set

flows, graphs

New Year and Entity Enumeration

bitmasks, combinatorics, dp, math

More Queries to Array...

data structures, math

Misha and Palindrome Degree

binary search, combinatorics, implementation

Attack on Red Kingdom

games, two pointers

Map

data structures, implementation, sortings

Maximum And Queries (hard version)

bitmasks, divide and conquer, dp, greedy

Traveling in Berland

binary search, data structures, graphs, greedy, implementation

Segments on the Line

binary search, dp

Colored Subgraphs

dfs and similar, dp, games, greedy, trees

Geometers Anonymous Club

data structures, geometry, math, sortings

Maze

dfs and similar, dp, probabilities, trees

The Child and Polygon

dp, geometry

Genetic engineering

dp, string suffix structures, trees

Even Split

binary search, constructive algorithms, greedy, math

Very simple problem

geometry, two pointers

Round Marriage

binary search, graph matchings, greedy

Degree Set

constructive algorithms, graphs, implementation

Binary Matrix

dsu

Hossam and a Letter

brute force, dp, implementation, two pointers

Power or XOR?

bitmasks, combinatorics, math, number theory

Function Sum

brute force, combinatorics, dp, fft, math

Inversion Composition

constructive algorithms, data structures, greedy

Number Table

combinatorics

Volcanoes

binary search, implementation, sortings, two pointers

Functions On The Segments

data structures

Minibuses on Venus (medium version)

combinatorics, divide and conquer, dp, matrices

Almost Increasing Array

data structures, dp

Yaroslav and Points

data structures

Recursive Queries

data structures

Spinach Pizza

games, geometry, greedy, interactive

Alice and the Unfair Game

binary search, data structures, dp, dsu

Cook and Porridge

binary search, constructive algorithms, data structures, implementation

Inverse Transformation

constructive algorithms, implementation, math

Magic multisets

data structures

Summer Practice Report

dp, greedy

CNF 2

constructive algorithms, dfs and similar, graphs, greedy

Italian Data Centers

graphs, shortest paths

Robot and Candies

data structures, graph matchings, greedy

Memory and Casinos

data structures, math, probabilities

Compute Power

binary search, dp, greedy

Tree

dp

Robot Arm

data structures, geometry

Igloo Skyscraper

data structures, geometry

Kingdom of Criticism

data structures, dsu

Rock-Paper-Scissors Champion

Babysitting

2-sat, binary search, data structures, graphs, trees

Minimal k-covering

flows, graphs

Path Counting

combinatorics, dp

Vus the Cossack and a Field

divide and conquer, implementation, math

Sereja and Sets

dp

Jeff and Brackets

dp, matrices

Multiset of Strings

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

Choosing Two Paths

dfs and similar, dp, greedy, trees

Crisp String

bitmasks, dp

AND-permutations

constructive algorithms

Sereja and Straight Lines

binary search, data structures, geometry, sortings, two pointers

Madoka and The First Session

constructive algorithms, flows, graph matchings, graphs, implementation

Virus

data structures, divide and conquer, dsu, graphs

Perun, Ult!

brute force, greedy, sortings

A Shade of Moonlight

binary search, geometry, math, sortings, two pointers

Gang Up

flows, graphs

Color the Carpet

constructive algorithms

Balance

constructive algorithms, dfs and similar, graphs, trees

Typewriter

brute force, math

Double Elimination

dp, implementation

Encryption (hard)

data structures, dp

L BREAK into program

*special problem

Candies and Stones

divide and conquer, dp

Rowena Ravenclaw's Diadem

trees

Max and Bike

binary search, geometry

Fetch the Treasure

brute force, data structures, graphs, shortest paths

String Transformation

hashing, strings

Tachibana Kanade's Tofu

dp

Plane Tiling

geometry, implementation, math

World of Darkraft

dp, games

Gifts from Grandfather Ahmed

dp, math, number theory

Write The Contest

binary search, dp, math

Polycarpus the Safecracker

brute force, dp

The Great Julya Calendar

dp