Wish I Knew How to Sort

dp, math, probabilities

Captain Marmot

brute force, geometry

Optimal Partition

data structures, dp

Watching Fireworks is Fun

data structures, dp, math

Weight the Tree

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

Recovering BST

brute force, dp, math, number theory, trees

Mishka and Interesting sum

data structures

We Need More Bosses

dfs and similar, graphs, trees

Array and Operations

flows, graph matchings, number theory

Cashback

data structures, dp, greedy, math

Mahmoud and a Dictionary

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

Robin Hood

binary search, greedy

Matching vs Independent Set

constructive algorithms, graphs, greedy, sortings

Sleepy Game

dfs and similar, dp, games, graphs

Triangular Paths

constructive algorithms, graphs, math, shortest paths, sortings

Complete the Projects (easy version)

greedy

Kirk and a Binary String (hard version)

data structures, greedy, math, strings

Best Pair

binary search, brute force, implementation

Common Number

binary search, combinatorics, dp, math

Bottom-Tier Reversals

constructive algorithms, greedy

Pencils and Boxes

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

Let's Play Osu!

dp, math, probabilities

Arena

combinatorics, dp, math

Equalizing Two Strings

constructive algorithms, sortings, strings

Counting Arrays

combinatorics, dp, math, number theory

Gourmet choice

dfs and similar, dp, dsu, graphs, greedy

Vasya and Good Sequences

bitmasks, dp

Inna and Pink Pony

greedy, implementation

Fox and Card Game

games, greedy, sortings

Graph Coloring

dfs and similar, dp, graphs

Interacdive Problem

binary search, constructive algorithms, interactive

Longest Subsequence

brute force, math, number theory

Circular Spanning Tree

constructive algorithms, implementation, trees

Looking for Order

bitmasks, dp

Vitya and Strange Lesson

binary search, data structures

Roman Digits

brute force, combinatorics, dp, greedy, math

Linguistics

greedy, implementation, sortings, strings

Points on Plane

constructive algorithms, divide and conquer, geometry, greedy, sortings

Kirk and a Binary String (easy version)

brute force, greedy, strings

Flying Sort (Easy Version)

dp, greedy, two pointers

Gluttony

constructive algorithms, greedy

Intercity Travelling

combinatorics, math, probabilities

Number of Components

combinatorics, data structures, dp, math

New Year's Puzzle

brute force, dp, graph matchings, greedy, sortings

Beautiful Mirrors

data structures, dp, math, probabilities

Drazil and Tiles

constructive algorithms, greedy

Send Boxes to Alice (Hard Version)

constructive algorithms, greedy, math, number theory, ternary search, two pointers

Euclid's nightmare

bitmasks, dfs and similar, dsu, graphs, greedy, math, sortings

Minimax

constructive algorithms, greedy, strings

Sergey and Subway

dfs and similar, dp, trees

MEX vs DIFF

binary search, brute force, constructive algorithms, data structures, greedy, two pointers

New Year and Conference

binary search, data structures, hashing, sortings

World of Darkraft: Battle for Azathoth

brute force, data structures, sortings

Vasya and Beautiful Arrays

brute force, dp, number theory

Pillars

binary search, data structures, dp, sortings, trees

Friends and Subsequences

binary search, data structures

Count the Trains

binary search, data structures, greedy, sortings

Dima and Bacteria

dsu, graphs, shortest paths

Famil Door and Brackets

dp, strings

Unusual Sequences

bitmasks, combinatorics, dp, math, number theory

Array Shuffling

constructive algorithms, graphs, greedy

Ability To Convert

constructive algorithms, dp, greedy, math, strings

Little Artem and Time Machine

data structures

OpenStreetMap

data structures, two pointers

Increase Sequence

combinatorics, dp

Thanos Nim

games

Bear and Tree Jumps

dfs and similar, dp, trees

Funny Substrings

data structures, hashing, implementation, matrices, strings

Skyline Photo

data structures, divide and conquer, dp

Treelabeling

bitmasks, constructive algorithms, dfs and similar, games, greedy, implementation, trees

Potion Brewing Class

dfs and similar, math, number theory, trees

GCD Queries

constructive algorithms, interactive, number theory

The LCMs Must be Large

bitmasks, brute force, constructive algorithms, math, number theory

Levko and Array

binary search, dp

Choosing Balls

dp

Queue

constructive algorithms, dp

Timofey and rectangles

constructive algorithms, geometry

Destruction of a Tree

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

Mahmoud and a xor trip

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

Into Blocks (easy version)

data structures, dsu, greedy, implementation, two pointers

Coprime Subsequences

bitmasks, combinatorics, number theory

Ehab and another another xor problem

bitmasks, constructive algorithms, implementation, interactive

Game on Sum (Easy Version)

combinatorics, dp, games, math

Breaking Good

dfs and similar, dp, graphs, shortest paths

Turn Off The TV

data structures, sortings

Shortest Path

graphs, shortest paths

Obsessive String

dp, strings

Segments Removal

data structures, dsu, flows, implementation, two pointers

How Many Paths?

dfs and similar, dp, graphs, trees

Berland Beauty

constructive algorithms, dfs and similar, greedy, sortings, trees

Editor

data structures, implementation

Domino (hard version)

constructive algorithms, implementation, math

Closest Equals

*special problem, data structures

Special Permutations

math

Rotate Columns (easy version)

bitmasks, brute force, dp, greedy, sortings

Games with Rectangle

combinatorics, dp

Portals

data structures, dp, greedy, implementation, sortings

Leaving Auction

binary search, data structures

Fibonacci-ish

brute force, dp, hashing, implementation, math

New Year and Ancient Prophecy

dp, hashing, strings