On Sum of Fractions

math, number theory

DZY Loves FFT

probabilities

Seller Bob

brute force, dp, greedy

Notepad

number theory

Maximum Questions

data structures, dp, strings

Teams Formation

data structures, implementation

XOR Counting

bitmasks, combinatorics, dp, math

Kicker

implementation

Little Elephant and Tree

data structures, dfs and similar, trees

Fractal Origami

geometry, math, matrices

Inversions After Shuffle

data structures, probabilities

Three strings

data structures, dsu, string suffix structures, strings

Divide, XOR, and Conquer

bitmasks, dp, math

Bandit Blues

combinatorics, dp, fft, math

House Planning

constructive algorithms, data structures, graph matchings, greedy

Minimal Product

Empire Strikes Back

binary search, math, number theory

Swap and Maximum Block

bitmasks, data structures, dfs and similar, divide and conquer, dp

Axel and Marston in Bitland

bitmasks, dp, graphs, matrices

World Eater Brothers

dfs and similar, dp, greedy, trees

Archaeology

data structures, dfs and similar, trees

Side Transmutations

combinatorics, strings

Magician and Pigs (Easy Version)

brute force, data structures, implementation

Oolimry and Suffix Array

combinatorics, constructive algorithms, math

TV Game

dp

Flag 2

dp

Game With String

games

Magic Matrix

brute force, divide and conquer, graphs, matrices, trees

Sagheer and Apple Tree

games, trees

Jeff and Removing Periods

data structures

Capitalism

constructive algorithms, dfs and similar, graphs, shortest paths

Dog Show

constructive algorithms, data structures, greedy

Number Transformation

dp, greedy, number theory

Online Meeting

implementation

Frequency Queries

data structures, dfs and similar, trees

Heidi and Library (medium)

data structures, greedy

Hidden Fortress

interactive, math

Sonya and Ice Cream

binary search, data structures, dp, greedy, shortest paths, trees

Good Contest

combinatorics, dp, probabilities

Lovely Matrix

dfs and similar, graphs, greedy, sortings

MST Company

binary search, graphs

Bulmart

binary search, dfs and similar

Divisor Tree

brute force, number theory, trees

Generate plus state or minus state

*special problem

Labeling the Tree with Distances

data structures, dp, greedy, hashing, implementation, trees

Gojou and Matrix Game

data structures, dp, games, hashing, implementation, math, number theory, sortings

Hongcow Buys a Deck of Cards

bitmasks, brute force, dp

Digits Permutations

greedy

Stranger Trees

dp, math, matrices, trees

Garlands

data structures

Rollbacks (Hard Version)

data structures, interactive, trees

Hiking

binary search, dp

Polycarp and the Language of Gods

*special problem, implementation, two pointers

Barrels and boxes

brute force, combinatorics, math, number theory, probabilities

Analyzing Polyline

geometry, math, sortings

Football Championship

brute force, implementation

Expression

*special problem, expression parsing

Array Equalizer

binary search, greedy, implementation, math, number theory, sortings, two pointers

Petya and File System

data structures, implementation

Dynamic Diameter

*special problem, data structures, dfs and similar, divide and conquer, trees

Demonstration

greedy

Bags with Balls

combinatorics, dp, math, number theory

Bad Days

*special problem, implementation

Xor-matic Number of the Graph

bitmasks, graphs, math, number theory, trees

Painting The Wall

dp, probabilities

Prime Problem

number theory

Travel to Bertown

*special problem, implementation, math

The Cake Is a Lie

constructive algorithms, data structures, dfs and similar, graphs

Crunching Numbers Just for You

*special problem, implementation

Roads in the Kingdom

dfs and similar, dp, graphs, trees

Flights

graphs, shortest paths

Il Derby della Madonnina

data structures, dp, math

Duff is Mad

data structures, strings

Zebra Tower

*special problem, data structures, greedy, sortings

Warehouse

implementation

Chocolate

dfs and similar, implementation

Vasya and Maximum Profit

binary search, constructive algorithms, data structures, dp, dsu

Martian Architecture

implementation

Interestring graph and Apples

dfs and similar, dsu, graphs

Parametric MST

binary search, constructive algorithms, graphs, greedy, math, sortings

Nauuo and Pictures (easy version)

dp, probabilities

Bulbo

dp, greedy

Game of Pairs

constructive algorithms, dfs and similar, interactive, math, number theory

Champions' League

implementation

Bath Queue

combinatorics, dp, probabilities

Closest Pair

data structures, greedy

Xor

brute force

Beavermuncher-0xFF

dfs and similar, dp, dsu, greedy, trees

Independent Set

dfs and similar, dp, trees

Runner's Problem

dp, matrices, sortings

New Year and the Acquaintance Estimation

binary search, data structures, graphs, greedy, implementation, math, sortings

Points, Lines and Ready-made Titles

dfs and similar, dsu, graphs, trees

Bacterial Melee

brute force, combinatorics, dp, string suffix structures

Cats on the Upgrade (easy version)

brute force, data structures, dfs and similar, divide and conquer, dp, graphs, trees

Summoning Minions

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

Choose a Square

binary search, data structures, sortings

Necklace

constructive algorithms, math

Variable, or There and Back Again

dfs and similar, graphs

Maximum Element

combinatorics, dp, math

Nudist Beach

binary search, graphs, greedy