How Many Paths?

dfs and similar, dp, graphs, trees

Nene and the Mex Operator

bitmasks, brute force, constructive algorithms, divide and conquer, dp, greedy, implementation, math

Sum Graph

brute force, constructive algorithms, graphs, implementation, interactive, shortest paths, trees

Mahmoud and a xor trip

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

Funny Substrings

data structures, hashing, implementation, matrices, strings

OpenStreetMap

data structures, two pointers

Dima and Bacteria

dsu, graphs, shortest paths

Euclid's nightmare

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

Bear and Tree Jumps

dfs and similar, dp, trees

Red-Blue Operations (Easy Version)

binary search, greedy, implementation, math

Counting Rhyme

dp, math, number theory

Potion Brewing Class

dfs and similar, math, number theory, trees

Tree with Small Distances

dp, graphs, greedy

Drazil and Tiles

constructive algorithms, greedy

Ehab and another another xor problem

bitmasks, constructive algorithms, implementation, interactive

Rectangular Congruence

constructive algorithms, number theory

Portals

data structures, dp, greedy, implementation, sortings

Famil Door and Brackets

dp, strings

Segments Removal

data structures, dsu, flows, implementation, two pointers

Anya and Cubes

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

Queue

constructive algorithms, dp

Wet Shark and Blocks

dp, matrices

Rotate Columns (easy version)

bitmasks, brute force, dp, greedy, sortings

Petr#

brute force, data structures, hashing, strings

Levko and Array

binary search, dp

Destruction of a Tree

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

Games with Rectangle

combinatorics, dp

Ability To Convert

constructive algorithms, dp, greedy, math, strings

Choosing The Commander

bitmasks, data structures, trees

Array Collapse

data structures, divide and conquer, dp, trees

The LCMs Must be Large

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

Berland Beauty

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

Pathwalks

data structures, dp, graphs

Choosing Balls

dp

ConstructOR

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

Domino (hard version)

constructive algorithms, implementation, math

Graph Cost

dp, greedy, math, number theory

Preorder

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

Relay Race

dp

Doremy's Pegging Game

combinatorics, dp, math

The Great Equalizer

binary search, data structures, math, sortings

Game of Stones

bitmasks, dp, games

Lynyrd Skynyrd

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

Speedrun

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

Breaking Good

dfs and similar, dp, graphs, shortest paths

Hossam and (sub-)palindromic tree

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

Promising String (hard version)

data structures, implementation, math, strings

Special Permutations

math

Timofey and rectangles

constructive algorithms, geometry

Not Quite Lee

combinatorics, dp, math, number theory

Obsessive String

dp, strings

Fibonacci-ish

brute force, dp, hashing, implementation, math

Playlist for Polycarp (easy version)

bitmasks, combinatorics, dp

Editor

data structures, implementation

Gadgets for dollars and pounds

binary search, greedy, two pointers

MST Unification

binary search, dsu, graphs, greedy

Cycle

dfs and similar, graphs

Shovels Shop

dp, greedy, sortings

Flexible String Revisit

combinatorics, dp, math, probabilities

Clique Partition

brute force, constructive algorithms, graphs, greedy, implementation

Minimization

dp, greedy, sortings

Leaving Auction

binary search, data structures

Paint the Tree

dp, sortings, trees

Maximum Balanced Circle

constructive algorithms, dp, greedy, two pointers

New Year and Ancient Prophecy

dp, hashing, strings

Cards and Joy

dp

Petya and Construction Set

constructive algorithms, graphs, math, sortings, trees

Count Binary Strings

data structures, dp

Jeremy Bearimy

dfs and similar, graphs, greedy, trees

Multicolored Markers

binary search, brute force, math, number theory

PolandBall and Polygon

data structures

Guess Game

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

Stack Sorting

constructive algorithms, data structures, greedy, implementation

Sad powers

binary search, math, number theory

String

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

Sheikh (Hard Version)

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

Colorings and Dominoes

combinatorics, dp, greedy, math

Polycarp and Snakes

brute force, implementation

Grime Zoo

brute force, greedy, implementation, strings

Tree Constructing

constructive algorithms, graphs

Freedom of Choice

brute force, greedy, implementation

Perfect Groups

dp, math, number theory

One-Dimensional Puzzle

combinatorics, math, number theory

Range Deleting

binary search, combinatorics, data structures, two pointers

Messages

brute force, dp, greedy, probabilities, sortings

Remove Directed Edges

dfs and similar, dp, graphs

Pinball

binary search, data structures, implementation, math, two pointers

You Are Given a WASD-string...

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

Two strings

binary search, hashing, strings, two pointers

Rain

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

Learning to Paint

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

Sum over all Substrings (Hard Version)

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

Mars rover

dfs and similar, graphs, implementation, trees

Wi-Fi

data structures, dp, greedy

Counting Binary Strings

combinatorics, dp, math

Counting Shortcuts

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

Unstable String Sort

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

Neko and Aki's Prank

dp, greedy, trees

Red-Black Number

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

Misha and Permutations Summation

data structures