George and Cards

binary search, data structures

Tree Recovery

brute force, constructive algorithms, dfs and similar, dsu, graphs, trees

Lamps on a Circle

games, implementation, interactive, math

Expected Square Beauty

dp, math, probabilities

Berland Elections

greedy, sortings

bHTML Tables Analisys

expression parsing

Strange LCS

bitmasks, dp, graphs, greedy, strings

Tree

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

Restore a Number

brute force, constructive algorithms, strings

Beautiful Road

dfs and similar, dp, dsu, graphs, implementation, sortings, trees

Beautiful Bracket Sequence (hard version)

combinatorics, probabilities

Ostap and Tree

dp, trees

Путь Робота

constructive algorithms, dfs and similar, graphs

Inna and Sequence

binary search, data structures, dp, trees

Anniversary

data structures, implementation, math, matrices, number theory

Mushroom Gnomes - 2

binary search, data structures, probabilities, sortings

Algebra Flash

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

Illusions of the Desert

data structures, trees

Diverse Segments

data structures, two pointers

Economic Difficulties

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

Vladik and Entertaining Flags

data structures, dsu, graphs

Max Mex

data structures, trees

Conveyor Belts

data structures

Strange Array

data structures, greedy, sortings

Closing ceremony

greedy

Space Rescuers

geometry, ternary search

Christmas Chocolates

dfs and similar, dp, games, graphs, implementation, math, number theory, shortest paths, trees

Instant Messanger

data structures

Points and Segments

graphs

Letter A

geometry, implementation

Small Permutation Problem (Hard Version)

combinatorics, dp, math

New Year and Handle Change

binary search, dp

Dasha and Chess

constructive algorithms, games, interactive

Kids' Riddle

*special problem

Opening Portals

dsu, graphs, shortest paths

Zbazi in Zeydabad

data structures, implementation

Nested Rubber Bands

constructive algorithms, dfs and similar, dp, math, trees

Helping People

dp, probabilities

Furlo and Rublo and Game

games, implementation, math

Groceries in Meteor Town

binary search, data structures, dsu, trees

Good Graph

data structures, dsu, graphs, trees

Balanced Domino Placements

combinatorics, dp

Tree Queries

data structures, dfs and similar, graphs, implementation, trees

April Fools' Problem (hard)

binary search, data structures, flows

Hot is Cold

bitmasks, data structures, divide and conquer, implementation

Serega the Pirate

brute force, constructive algorithms

Lena and Queries

data structures, divide and conquer, geometry

Power Sockets

binary search, data structures, greedy

Parquet

combinatorics, constructive algorithms, greedy, implementation

Survival of the Weakest (easy version)

binary search, brute force, implementation, math, sortings

The Tree Has Fallen!

bitmasks, dfs and similar, math, trees

Indecisive Taxi Fee

data structures, graphs, shortest paths

Numbers

dp, math, number theory

Balancing Weapons

binary search, brute force, data structures, math, two pointers

Comfortably Numb

bitmasks, data structures, divide and conquer, strings, trees

Generate superposition of all basis states

Colorful Constructive

constructive algorithms, data structures, greedy

Split

binary search, data structures, divide and conquer, dsu, math, trees, two pointers

Slime and Biscuits

math, probabilities

Frog Jumping

*special problem, math

GCD Groups 2

greedy, number theory, probabilities

Buying Sets

flows, graph matchings

Lexichromatography

combinatorics, dfs and similar, dsu, graphs, two pointers

Code Review

*special problem

Airplane Arrangements

math, number theory

Ladies' Shop

constructive algorithms, fft, math

Balance

dp

Alphabet Permutations

data structures, strings

Max Sum Array

combinatorics, constructive algorithms, greedy, sortings

Monsters and Potions

brute force, dp, greedy, implementation

The Tree

data structures

Apprentice Learning Trajectory

Nauuo and Pictures (hard version)

dp, probabilities

Guess Divisors Count

constructive algorithms, interactive, number theory

Wise Men (Easy Version)

bitmasks, brute force, dp, meet-in-the-middle

The Supersonic Rocket

geometry, hashing, strings

Gotta Go Fast

binary search, dp

PolandBall and White-Red graph

constructive algorithms, graphs, shortest paths

Curfew

binary search, brute force, greedy, sortings

Baby Ehab Plays with Permutations

combinatorics, dp, math

Clearing Up

constructive algorithms, dp, dsu, graphs

Contact ATC

A Museum Robbery

data structures, dp

Divan and a Cottage

binary search, data structures

Abnormal Permutation Pairs (hard version)

combinatorics, dp, fft, math

Playing on Graph

graphs, shortest paths

Casinos and travel

dp

Singer House

combinatorics, dp, graphs, trees

E-mail Addresses

implementation

Table with Letters - 2

brute force, two pointers

Brand New Easy Problem

brute force

Off by One

constructive algorithms, dfs and similar, geometry, graphs, sortings, trees

Boboniu and Jianghu

dp, greedy, sortings, trees

Fibonacci Sums

dp, math

Even Harder

dp

Danger of Mad Snakes

combinatorics, dp, math

Thwarting Demonstrations

binary search, data structures, trees

Village (Maximum)

*special problem, dfs and similar, trees

Superset

constructive algorithms, divide and conquer

Nastya and Time Machine

constructive algorithms, dfs and similar, graphs, trees