Lenient Vertex Cover

dfs and similar, divide and conquer, dsu, graphs, trees

Maximum Crossings (Hard Version)

data structures, divide and conquer, sortings

Anti-Theft Road Planning

bitmasks, constructive algorithms, divide and conquer, greedy, interactive, math

Preorder

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

MinimizOR

bitmasks, brute force, data structures, divide and conquer, greedy, implementation, two pointers

Mike's Sequence

divide and conquer, implementation, math

Three Minimums

combinatorics, constructive algorithms, divide and conquer, dp, fft, math

Minimal String Xoration

bitmasks, data structures, divide and conquer, greedy, hashing, sortings, strings

Air Reform

data structures, dfs and similar, divide and conquer, dsu, graphs, implementation, trees

Serious Business

data structures, divide and conquer, dp, implementation, shortest paths

Special Positions

combinatorics, divide and conquer, fft, math

Perfect Matching

data structures, divide and conquer, interactive, trees

Cats on the Upgrade (easy version)

brute force, data structures, dfs and similar, divide and conquer, dp, graphs, trees

Permutation and Queries

brute force, data structures, divide and conquer, two pointers

Keep XOR Low

bitmasks, combinatorics, data structures, divide and conquer, dp, math

Reindeer Games

binary search, constructive algorithms, data structures, divide and conquer, flows, graphs, shortest paths

Tree Coloring

combinatorics, divide and conquer, fft

Interesting Sections

data structures, divide and conquer, meet-in-the-middle, two pointers

Artistic Partition

divide and conquer, dp, number theory

Optimal Insertion

data structures, divide and conquer, dp, greedy, sortings

Omkar and Tours

data structures, divide and conquer, sortings, trees

Defender of Childhood Dreams

bitmasks, constructive algorithms, divide and conquer

Subsequence

brute force, divide and conquer, dp, greedy, trees

Longest Array Deconstruction

data structures, divide and conquer, dp, sortings

Non-Decreasing Dilemma

data structures, divide and conquer, math

Stairs

combinatorics, divide and conquer, dp, fft, math

XOR and Distance

bitmasks, divide and conquer, trees

Jumping Around

binary search, data structures, divide and conquer, dp, dsu, graphs, shortest paths

Gregor and the Two Painters

data structures, divide and conquer, graphs, greedy, math

Integers Have Friends

binary search, data structures, divide and conquer, math, number theory, two pointers

Array Stabilization (GCD version)

binary search, brute force, data structures, divide and conquer, number theory, two pointers

The Final Pursuit

bitmasks, constructive algorithms, divide and conquer, graphs, greedy, math

Parsa's Humongous Tree

dfs and similar, divide and conquer, dp, greedy, trees

Partition Game

binary search, data structures, divide and conquer, dp

Try Booking

data structures, divide and conquer

Balance the Cards

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

Dogeforces

constructive algorithms, data structures, dfs and similar, divide and conquer, dsu, greedy, sortings, trees

Fib-tree

brute force, dfs and similar, divide and conquer, number theory, trees

Permutation Transformation

dfs and similar, divide and conquer, implementation

Skyline Photo

data structures, divide and conquer, dp

Strange Covering

divide and conquer

Song of the Sirens

combinatorics, divide and conquer, hashing, math, string suffix structures, strings

Divide and Summarize

binary search, brute force, data structures, divide and conquer, implementation, sortings

Xor Tree

binary search, bitmasks, data structures, divide and conquer, dp, trees

Sum

data structures, divide and conquer, dp, greedy

Greedy Shopping

binary search, data structures, divide and conquer, greedy, implementation

Yurii Can Do Everything

binary search, bitmasks, brute force, constructive algorithms, divide and conquer, two pointers

Fruit Sequences

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

Blue and Red of Our Faculty!

divide and conquer, dp

Virus

data structures, divide and conquer, dsu, graphs

Dušan's Railway

divide and conquer, graphs, trees

Pokémon Army (hard version)

data structures, divide and conquer, dp, greedy, implementation

Three Occurrences

data structures, divide and conquer, hashing, two pointers

XOR Inverse

bitmasks, data structures, divide and conquer, dp, greedy, math, sortings, strings, trees

Two Different

constructive algorithms, divide and conquer

Clear the Multiset

data structures, divide and conquer, dp, greedy

Joker

*special problem, bitmasks, data structures, divide and conquer, dsu

a-Good String

bitmasks, brute force, divide and conquer, dp, implementation

Chess Strikes Back (hard version)

data structures, divide and conquer

Inverse Genealogy

constructive algorithms, divide and conquer, dp, math, trees

Set Merging

constructive algorithms, divide and conquer

Pawns

data structures, divide and conquer, greedy

Maximum Sum on Even Positions

divide and conquer, dp, greedy, implementation

Omkar and Modes

binary search, divide and conquer, interactive

Raging Thunder

data structures, divide and conquer, implementation

X-OR

bitmasks, constructive algorithms, divide and conquer, interactive, probabilities

Perfect Triples

bitmasks, brute force, constructive algorithms, divide and conquer, math

Journey

data structures, divide and conquer, graphs, trees

Battalion Strength

data structures, divide and conquer, probabilities

Moving Points

data structures, divide and conquer, implementation, sortings

Sum of Prefix Sums

data structures, divide and conquer, geometry, trees

Permutation Separation

data structures, divide and conquer

Dr. Evil Underscores

bitmasks, brute force, dfs and similar, divide and conquer, dp, greedy, strings, trees

Tests for problem D

constructive algorithms, dfs and similar, divide and conquer, trees

Invertation in Tournament

brute force, divide and conquer, graphs, math

Xor-Set

bitmasks, divide and conquer, math

Divisor Set

divide and conquer, fft, greedy, math, number theory

SmartGarden

constructive algorithms, divide and conquer

Balanced Removals (Harder)

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

Stack Exterminable Arrays

data structures, divide and conquer, dp, hashing

Product Tuples

divide and conquer, fft

Xor Spanning Tree

divide and conquer, fft, graphs

Forced Online Queries Problem

data structures, divide and conquer, dsu, graphs, trees

Path Queries

divide and conquer, dsu, graphs, sortings, trees

Dynamic Diameter

*special problem, data structures, dfs and similar, divide and conquer, trees

Tokitsukaze and Strange Rectangle

data structures, divide and conquer, sortings, two pointers

Vus the Cossack and a Field

divide and conquer, implementation, math

A Story of One Country (Easy)

brute force, divide and conquer, sortings

Alesya and Discrete Math

divide and conquer, interactive

Digits Sequence (Hard Edition)

binary search, divide and conquer, implementation

Yet Another Partiton Problem

data structures, divide and conquer, dp, geometry, two pointers

The Number of Subpermutations

brute force, data structures, divide and conquer, hashing, math

Minimal Segment Cover

data structures, dfs and similar, divide and conquer, dp, greedy, implementation, trees

Ehab and the Big Finale

constructive algorithms, divide and conquer, graphs, implementation, interactive, trees

Lost Numbers

brute force, divide and conquer, interactive, math

Special Segments of Permutation

data structures, divide and conquer, dsu, two pointers

0-1-Tree

dfs and similar, divide and conquer, dp, dsu, trees

Beautiful Array

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

Hot is Cold

bitmasks, data structures, divide and conquer, implementation

Double Tree

data structures, divide and conquer, shortest paths, trees