Balanced Removals (Harder)

binary search, constructive algorithms, divide and conquer, greedy, implementation, sortings

Special Permutations

math

Complete Tripartite

brute force, constructive algorithms, graphs, hashing, implementation

Paint the Tree

dp, sortings, trees

Sequence Sorting

dp, greedy, two pointers

Alex and Julian

bitmasks, math, number theory

Harvester

implementation

The Light Square

2-sat, dfs and similar, greedy

Coloring Edges

constructive algorithms, dfs and similar, graphs

Wi-Fi

data structures, dp, greedy

Numerical Sequence (easy version)

binary search, brute force, math

Petya and Construction Set

constructive algorithms, graphs, math, sortings, trees

Treasure Island

dfs and similar, dp, flows, hashing

Unstable String Sort

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

Two Small Strings

brute force, constructive algorithms

Double Permutation Inc.

*special problem, binary search, greedy

Teams

*special problem, binary search, greedy, math

Kamil and Making a Stream

math, number theory, trees

Into Blocks (easy version)

data structures, dsu, greedy, implementation, two pointers

Rotate Columns (easy version)

bitmasks, brute force, dp, greedy, sortings

Restore Permutation

binary search, data structures, greedy, implementation

Remainder Problem

brute force, data structures, implementation

XOR Guessing

bitmasks, interactive, math

Shortest Cycle

bitmasks, brute force, graphs, shortest paths

Kirk and a Binary String (hard version)

data structures, greedy, math, strings

Kirk and a Binary String (easy version)

brute force, greedy, strings

Complete the Projects (easy version)

greedy

Print a 1337-string...

combinatorics, constructive algorithms, math, strings

You Are Given a WASD-string...

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

Treasure Hunting

binary search, dp, greedy, implementation

Compress Words

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

White Lines

brute force, data structures, dp, implementation, two pointers

Matching vs Independent Set

constructive algorithms, graphs, greedy, sortings

Yet Another Subarray Problem

dp, greedy, math

OpenStreetMap

data structures, two pointers

Tokitsukaze and Strange Rectangle

data structures, divide and conquer, sortings, two pointers

Tree Painting

dfs and similar, dp, trees

Playlist for Polycarp (easy version)

bitmasks, combinatorics, dp

Two Pizzas

bitmasks, brute force

Polycarp and Snakes

brute force, implementation

Daleks' Invasion (medium)

dfs and similar, graphs, shortest paths, trees

Daleks' Invasion (easy)

graphs, trees

Heidi Learns Hashing (Medium)

brute force, number theory

Subsequences (hard version)

dp, strings

Candy Box (hard version)

greedy, implementation, sortings

Topforces Strikes Back

brute force, math, sortings

Subsequences (easy version)

dp, graphs, implementation, shortest paths

Flag

brute force, combinatorics, dp, implementation

Archaeology

brute force, constructive algorithms, greedy, strings

Destroy it!

dp, implementation, sortings

Array Splitting

greedy, sortings

Ehab and the Expected XOR Problem

bitmasks, constructive algorithms

Nauuo and Circle

combinatorics, dfs and similar, dp, trees

Good Triple

brute force, two pointers

Range Deleting

binary search, combinatorics, data structures, two pointers

The LCMs Must be Large

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

Microtransactions (hard version)

binary search, greedy, implementation

Microtransactions (easy version)

binary search, greedy

Mysterious Code

dp, strings

Power Transmission (Hard Edition)

data structures, geometry, implementation, math

Power Transmission (Easy Edition)

brute force, geometry

Permutation recovery

constructive algorithms, data structures, dfs and similar, graphs, greedy, math, sortings

Maximum Balanced Circle

constructive algorithms, dp, greedy, two pointers

N Problems During K Days

constructive algorithms, greedy, math

Match Points

binary search, greedy, sortings, ternary search, two pointers

Beautiful Array

brute force, data structures, divide and conquer, dp, greedy

Shovels Shop

dp, greedy, sortings

Serval and Rooted Tree

binary search, dfs and similar, dp, greedy, trees

Neko and Aki's Prank

dp, greedy, trees

Number of Components

combinatorics, data structures, dp, math

Thanos Nim

games

Chladni Figure

brute force, strings

Frog Jumping

dfs and similar, math, number theory

Median String

bitmasks, math, number theory, strings

Lynyrd Skynyrd

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

Privatization of Roads in Treeland

binary search, constructive algorithms, dfs and similar, graphs, greedy, trees

Same Sum Blocks (Hard)

data structures, greedy

Same Sum Blocks (Easy)

greedy

Spanning Tree with One Fixed Degree

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

Clear the String

dp

Gourmet choice

dfs and similar, dp, dsu, graphs, greedy

Wrong Answer

constructive algorithms

Compress String

dp, strings

Diana and Liana

greedy, implementation, two pointers

Pavel and Triangles

brute force, dp, fft, greedy, ternary search

Magic Gems

dp, math, matrices

Magic Ship

binary search

Flood Fill

dp

MST Unification

binary search, dsu, graphs, greedy

Array and Segments (Hard version)

data structures, implementation

Lunar New Year and Red Envelopes

data structures, dp

Kilani and the Game

dfs and similar, graphs, implementation, shortest paths

Game with modulo

binary search, constructive algorithms, interactive

Elongated Matrix

binary search, bitmasks, brute force, dp, graphs

GCD Counting

data structures, dfs and similar, dp, number theory, trees

Nice table

brute force, constructive algorithms, greedy, math

Make It Connected

dsu, graphs, greedy

Almost Regular Bracket Sequence

implementation

Tree with Maximum Cost

dfs and similar, dp, trees

Minimal Diameter Forest

constructive algorithms, dfs and similar, greedy, trees