Square-free division (hard version)

data structures, dp, greedy, math, number theory, two pointers

LaIS

data structures, dp, greedy

Letters Removing

data structures, strings

Beard Graph

data structures, dsu, trees

Long Way Home

data structures, divide and conquer, dp, geometry, graphs, greedy, shortest paths

Fair Share

constructive algorithms, data structures, dfs and similar, graph matchings, graphs

Sasha and the Wedding Binary Search Tree

brute force, combinatorics, data structures, dfs and similar, math, trees

Ann and Books

data structures, flows, hashing

Vlad and the Nice Paths (hard version)

binary search, combinatorics, data structures, dp, math, two pointers

Frequency Problem (Easy Version)

data structures, greedy

AND Segments

bitmasks, combinatorics, data structures, dp, two pointers

Lucky Array

data structures

DNA Evolution

data structures, strings

Changing Brackets

constructive algorithms, data structures, dp, greedy

Artem and Array

data structures, greedy

Network Coverage

binary search, constructive algorithms, data structures, greedy

Mister B and PR Shifts

data structures, implementation, math

Arthur and Walls

constructive algorithms, data structures, graphs, greedy, shortest paths

You Are Given a Tree

data structures, dp, trees

Yet Another Inversions Problem

combinatorics, data structures, dp, implementation, math, number theory

Sum Queries?

data structures, greedy, implementation, math

Alice and the Doll

brute force, data structures, greedy, implementation

Red-Black Pepper

brute force, data structures, greedy, math, number theory

Insertion Sort

data structures, dp, implementation, math

Chopping Carrots (Hard Version)

brute force, constructive algorithms, data structures, dp, greedy, math, number theory, two pointers

Subtree Minimum Query

data structures, trees

GukiZ and GukiZiana

binary search, data structures, implementation

A-Z Graph

constructive algorithms, data structures, graphs, hashing

Delete a Segment

brute force, constructive algorithms, data structures, dp, graphs, sortings, trees, two pointers

Train Maintenance

brute force, data structures, implementation

K Integers

binary search, data structures

String Set Queries

brute force, data structures, hashing, interactive, string suffix structures, strings

Greedy Shopping

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

Colorful Points

data structures, greedy, implementation

Nearest Leaf

data structures, trees

Kuro and GCD and XOR and SUM

binary search, bitmasks, brute force, data structures, dp, dsu, greedy, math, number theory, strings, trees

Permutation recovery

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

Yet Another Array Counting Problem

binary search, data structures, divide and conquer, dp, flows, math, trees

Company

binary search, data structures, dfs and similar, greedy, trees

Order book

combinatorics, data structures, greedy

New School

binary search, data structures, dp, greedy, implementation, sortings

Beaver

data structures, dp, greedy, hashing, strings, two pointers

Big Maximum Sum

data structures, dp, greedy, implementation, math, trees

Two Strings

data structures, dp, strings

Xor-Subsequence (hard version)

bitmasks, data structures, dp, strings, trees

Leaving the Bar

brute force, data structures, geometry, greedy, math, sortings

Count The Rectangles

bitmasks, brute force, data structures, geometry, sortings

Number of Groups

data structures, dfs and similar, dsu, graphs, greedy, sortings

Range Sorting (Hard Version)

binary search, data structures, dp, greedy

Broken BST

data structures, dfs and similar

Sereja and Subsequences

data structures, dp

Colors and Intervals

constructive algorithms, data structures, greedy, sortings

Encrypting Messages

data structures

TorCoder

data structures

Anton and Permutation

brute force, data structures

Addition Robot

data structures, math, matrices

Colorful Operations

brute force, data structures, implementation

Nastia Plays with a Tree

constructive algorithms, data structures, dfs and similar, dp, dsu, greedy, implementation, trees

The Number Games

data structures, greedy, trees

Mike and Geometry Problem

combinatorics, data structures, dp, geometry, implementation

Please, another Queries on Array?

bitmasks, data structures, divide and conquer, math, number theory

Santa Claus and a Palindrome

constructive algorithms, data structures, greedy

Rooter's Song

constructive algorithms, data structures, geometry, implementation, sortings, two pointers

Graph and Queries

data structures, dsu, graphs, implementation, trees

Multidimensional Queries

bitmasks, data structures

Accumulator Apex

data structures, implementation, sortings

William The Oblivious

bitmasks, data structures, dp, matrices

Souvenirs

data structures

Copy or Prefix Sum

combinatorics, data structures, dp, sortings

Card Game Again

binary search, data structures, number theory, two pointers

Boxes And Balls

data structures, greedy

Fill the Matrix

data structures, greedy, math

Avoid Rainbow Cycles

data structures, dsu, graphs, greedy, sortings, trees

Castle Defense

binary search, data structures, greedy, two pointers

Merging Towers

data structures, dsu, implementation, trees

Explosions?

binary search, data structures, dp, greedy, math

Sum of Medians

binary search, brute force, data structures, implementation

Optimal Insertion

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

Sum

data structures, divide and conquer, dp, greedy

Mike and Friends

data structures, string suffix structures, strings, trees

Kefa and Watch

data structures, hashing, strings

Fishes

data structures, graphs, greedy, probabilities, shortest paths

Omkar and Landslide

binary search, constructive algorithms, data structures, greedy, math

Stack Exterminable Arrays

data structures, divide and conquer, dp, hashing

Case of Chocolate

data structures

Ball

data structures, sortings

Serge and Dining Room

binary search, data structures, graph matchings, greedy, implementation, math, trees

Running with Obstacles

*special problem, data structures, dp, greedy

Bombs

data structures, two pointers

Let Them Slide

data structures, implementation

Robots on a Grid

data structures, dfs and similar, dsu, graphs, greedy, matrices

Check Transcription

brute force, data structures, hashing, strings

Welcome home, Chtholly

data structures, dsu

Time to Raid Cowavans

brute force, data structures, sortings

Binary Spiders

bitmasks, data structures, implementation, math, sortings, trees

High Cry

binary search, bitmasks, combinatorics, data structures, divide and conquer

Mark and Professor Koro

binary search, bitmasks, brute force, combinatorics, data structures, greedy

Preparing for the Contest

binary search, data structures, greedy, sortings

Messenger

data structures, hashing, implementation, string suffix structures, strings

Cyclical Quest

data structures, string suffix structures, strings