The Holmes Children

math, number theory

Towers

dp, greedy, two pointers

Random Task

binary search, bitmasks, combinatorics, dp, math

Yaroslav and Time

binary search, graphs, shortest paths

The Queue

brute force, greedy

Array and Segments (Hard version)

data structures, implementation

Autosynthesis

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

Polygons

geometry, sortings

Turtle Mission: Robot and the Earthquake

dfs and similar, dp, graphs, shortest paths

Petya, Petya, Petr, and Palindromes

binary search, brute force, data structures, two pointers

Fedor and coupons

binary search, data structures, greedy, sortings

Ralph and Mushrooms

dp, graphs

Treasure Hunting

binary search, dp, greedy, implementation

Ball Sorting

data structures, dp, sortings

Well played!

greedy, sortings

The Harmonization of XOR

bitmasks, constructive algorithms, greedy, math

Mashmokh and Reverse Operation

combinatorics, divide and conquer

Rain and Umbrellas

dp

Cartons of milk

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

Rearrange Brackets

brute force, dp, greedy, sortings, strings

Space Harbour

data structures, implementation, math, sortings

Staircases

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

Leha and another game about graph

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

Neko and Aki's Prank

dp, greedy, trees

Sand Fortress

binary search, constructive algorithms, math

Hot Start Up (hard version)

data structures, dp

Learning to Paint

binary search, data structures, dfs and similar, dp, greedy, implementation, sortings

Candy Party (Hard Version)

bitmasks, constructive algorithms, dp, greedy, implementation, math

Analysis of Pathes in Functional Graph

data structures, graphs

Subway Pursuit

binary search, interactive, probabilities

Weird journey

combinatorics, constructive algorithms, dfs and similar, dsu, graphs

Underground Lab

constructive algorithms, dfs and similar, graphs

Counting Binary Strings

combinatorics, dp, math

Unstable String Sort

data structures, dfs and similar, dsu, graphs, greedy, implementation, strings

Lunar New Year and Red Envelopes

data structures, dp

Sum over all Substrings (Hard Version)

bitmasks, divide and conquer, dp, dsu, greedy, implementation, strings

Carry Bit

combinatorics, math

Red-Black Number

dfs and similar, dp, implementation, math, meet-in-the-middle

Wi-Fi

data structures, dp, greedy

Counting Shortcuts

data structures, dfs and similar, dp, graphs, shortest paths

You Are Given a WASD-string...

brute force, data structures, dp, greedy, implementation, math, strings

Rain

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

Two strings

binary search, hashing, strings, two pointers

Range Deleting

binary search, combinatorics, data structures, two pointers

Perfect Groups

dp, math, number theory

Tree Constructing

constructive algorithms, graphs

Grime Zoo

brute force, greedy, implementation, strings

Sheikh (Hard Version)

binary search, bitmasks, brute force, greedy, implementation, two pointers

Clique Partition

brute force, constructive algorithms, graphs, greedy, implementation

Colorings and Dominoes

combinatorics, dp, greedy, math

Sad powers

binary search, math, number theory

String

brute force, constructive algorithms, hashing, implementation, string suffix structures, strings

Guess Game

bitmasks, data structures, games, math, probabilities, sortings, strings, trees

Count Binary Strings

data structures, dp

Paint the Tree

dp, sortings, trees

Flexible String Revisit

combinatorics, dp, math, probabilities

Shovels Shop

dp, greedy, sortings

Playlist for Polycarp (easy version)

bitmasks, combinatorics, dp

MST Unification

binary search, dsu, graphs, greedy

Editor

data structures, implementation

Timofey and rectangles

constructive algorithms, geometry

Hossam and (sub-)palindromic tree

brute force, data structures, dfs and similar, dp, strings, trees

Promising String (hard version)

data structures, implementation, math, strings

Speedrun

brute force, dfs and similar, dp, graphs, greedy, math, sortings, two pointers

Breaking Good

dfs and similar, dp, graphs, shortest paths

Game of Stones

bitmasks, dp, games

Berland Beauty

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

Preorder

combinatorics, divide and conquer, dp, dsu, hashing, sortings, trees

The LCMs Must be Large

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

Domino (hard version)

constructive algorithms, implementation, math

ConstructOR

bitmasks, chinese remainder theorem, combinatorics, constructive algorithms, math, number theory

Array Collapse

data structures, divide and conquer, dp, trees

Pathwalks

data structures, dp, graphs

Anya and Cubes

binary search, bitmasks, brute force, dp, math, meet-in-the-middle

Rectangular Congruence

constructive algorithms, number theory

Portals

data structures, dp, greedy, implementation, sortings

Counting Rhyme

dp, math, number theory

Tree with Small Distances

dp, graphs, greedy

How Many Paths?

dfs and similar, dp, graphs, trees

Potion Brewing Class

dfs and similar, math, number theory, trees

Red-Blue Operations (Easy Version)

binary search, greedy, implementation, math

Bear and Tree Jumps

dfs and similar, dp, trees

Euclid's nightmare

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

Funny Substrings

data structures, hashing, implementation, matrices, strings

OpenStreetMap

data structures, two pointers

Mahmoud and a xor trip

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

Increase Sequence

combinatorics, dp

Treelabeling

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

Pictures with Kittens (hard version)

data structures, dp

Beautiful Subarrays

data structures, divide and conquer, strings, trees

Minimax

constructive algorithms, greedy, strings

New Year and Conference

binary search, data structures, hashing, sortings

Skyline Photo

data structures, divide and conquer, dp

Send Boxes to Alice (Hard Version)

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

New Year's Puzzle

brute force, dp, graph matchings, greedy, sortings

Monsters

brute force, data structures, dfs and similar, dsu, graphs, greedy

XOR Break --- Solo Version

bitmasks, constructive algorithms, greedy

Vasya and Beautiful Arrays

brute force, dp, number theory

Kirk and a Binary String (hard version)

data structures, greedy, math, strings

Flying Sort (Easy Version)

dp, greedy, two pointers