Marvolo Gaunt's Ring

brute force, data structures, dp

Lada Malina

data structures, geometry

Boredom

data structures

Goodbye Souvenir

data structures, divide and conquer

Rooter's Song

constructive algorithms, data structures, geometry, implementation, sortings, two pointers

Dog Show

constructive algorithms, data structures, greedy

Preparing for Merge Sort

binary search, data structures

Random Query

data structures, math, probabilities, two pointers

Monitor

binary search, data structures

Four Segments

brute force, data structures, dp

Fire in the City

binary search, data structures

Driving Test

data structures, dp, greedy

Two TVs

data structures, greedy, sortings

Vitya and Strange Lesson

binary search, data structures

Destiny

data structures, probabilities

Leha and another game about graph

constructive algorithms, data structures, dfs and similar, dp, graphs

Diverging Directions

data structures, dfs and similar, trees

Functions On The Segments

data structures

The Festive Evening

data structures, implementation

Caramel Clouds

data structures, dp, sortings

Red-Black Cobweb

data structures, divide and conquer, implementation, trees

The Bakery

binary search, data structures, divide and conquer, dp, two pointers

Bamboo Partition

brute force, data structures, implementation, math, number theory, sortings, two pointers

Cards Sorting

data structures, implementation, sortings

Dirty Arkady's Kitchen

data structures, dp, graphs, shortest paths

Best Edge Weight

data structures, dfs and similar, graphs, trees

DNA Evolution

data structures, strings

String Reconstruction

data structures, greedy, sortings, strings

Minimal Labels

data structures, dfs and similar, graphs, greedy

Okabe and Boxes

data structures, greedy, trees

Mister B and PR Shifts

data structures, implementation, math

Card Game Again

binary search, data structures, number theory, two pointers

Multicolored Cars

data structures, implementation

MEX Queries

binary search, data structures, trees

Choosing The Commander

bitmasks, data structures, trees

Imbalanced Array

data structures, divide and conquer, dsu, sortings

Karen and Coffee

binary search, data structures, implementation

Karen and Cards

binary search, combinatorics, data structures, geometry

Bipartite Checking

data structures, dsu, graphs

Army Creation

binary search, data structures

Vladik and Entertaining Flags

data structures, dsu, graphs

Hitchhiking in the Baltic States

data structures, dp

Array Division

binary search, data structures, implementation

Average Sleep Time

data structures, implementation, math

Periodic RMQ Problem

data structures

April Fools' Problem (hard)

binary search, data structures, flows

Heidi and Library (medium)

data structures, greedy

Cut the pie

binary search, data structures, geometry

Beautiful fountains rows

data structures

Aquarium decoration

data structures, greedy, two pointers

Fountains

binary search, data structures, implementation

T-shirt buying

data structures, implementation

Mike and code of a permutation

constructive algorithms, data structures, graphs, sortings

Mice and Holes

data structures, dp, greedy, sortings

Array Queries

brute force, data structures, dp

Broken BST

data structures, dfs and similar

Minimal string

data structures, greedy, strings

Sequence Recovery

bitmasks, data structures, greedy

Bank Hacking

constructive algorithms, data structures, dp, trees

Leha and security system

data structures

Oleg and chess

data structures, divide and conquer, flows, graph matchings

Julia the snail

data structures, divide and conquer, dp

Mages and Monsters

data structures, geometry

New task

data structures

ALT

data structures, flows, graphs, trees

Rap God

data structures, dfs and similar, hashing, strings, trees

Till I Collapse

data structures, divide and conquer

Legacy

data structures, graphs, shortest paths

Anton and Permutation

brute force, data structures

Andryusha and Nervous Barriers

data structures, dp

Hanoi Factory

brute force, data structures, dp, greedy, sortings

Alyona and Spreadsheet

binary search, data structures, dp, greedy, implementation, two pointers

Game of Credit Cards

data structures, dp, greedy, sortings

Sherlock's bet to Moriarty

constructive algorithms, data structures, divide and conquer, geometry, graphs, implementation, trees

Molly's Chemicals

binary search, brute force, data structures, implementation, math

Significant Cups

*special problem, binary search, data structures, two pointers

Blog Post Rating

data structures, sortings

The Winds of Winter

binary search, data structures

Cartons of milk

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

Snacktower

data structures, implementation

Mahmoud and a xor trip

bitmasks, constructive algorithms, data structures, dfs and similar, dp, math, trees

Mahmoud and a Dictionary

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

Souvenirs

data structures

Timofey and our friends animals

data structures, divide and conquer, dsu

Timofey and a flat tree

data structures, graphs, hashing, shortest paths, trees

Radio stations

binary search, data structures

Dasha and Photos

brute force, data structures, dp, implementation

Can Bash Save the Day?

data structures, divide and conquer, graphs, trees

Team Rocket Rises Again

data structures, graphs, shortest paths

Felicity is Coming!

data structures, hashing, sortings, strings

Nikita and stack

data structures

PolandBall and Polygon

data structures

PolandBall and Game

binary search, data structures, games, greedy, sortings, strings

Fedor and coupons

binary search, data structures, greedy, sortings

New Year and Old Subsequence

data structures, divide and conquer, dp, matrices

New Year and Fireworks

brute force, data structures, dfs and similar, dp, implementation

Inversions After Shuffle

data structures, probabilities

Leaving Auction

binary search, data structures

Santa Claus and Tangerines

binary search, data structures, greedy, two pointers

Santa Claus and a Palindrome

constructive algorithms, data structures, greedy