MEX vs MED

math, two pointers

Divisible Numbers (hard version)

brute force, math, number theory

Multi-Colored Segments

binary search, data structures, math, sortings

Reset K Edges

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

Permutation Addicts

constructive algorithms, data structures, dfs and similar, dsu, graphs, trees

Rectangular Congruence

constructive algorithms, number theory

Zero-One (Hard Version)

dp, greedy

Sheikh (Hard Version)

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

Graph Cost

dp, greedy, math, number theory

Cut Substrings

combinatorics, dp, hashing, strings, two pointers

Kirei and the Linear Function

hashing, math

Edge Split

brute force, constructive algorithms, dfs and similar, dsu, graphs, probabilities, trees

Field Photography

bitmasks, data structures, sortings

Circular Mirror

binary search, combinatorics, geometry, math, two pointers

Fibonacci Strings

greedy, implementation, math, number theory

Burenka and Traditions (hard version)

data structures, dp, greedy

Madoka and The Corruption Scheme

combinatorics, constructive algorithms, greedy, math

Chip Move

brute force, dp, math

Robot in a Hallway

data structures, dp, greedy, implementation, ternary search

2+ doors

2-sat, bitmasks, graphs, greedy

Build a Tree and That Is It

constructive algorithms, implementation, trees

Empty Graph

binary search, constructive algorithms, data structures, greedy, shortest paths

Rain

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

Difference Array

brute force, data structures, implementation, sortings

Magical Array

constructive algorithms, hashing, implementation, math

Passable Paths (hard version)

data structures, dfs and similar, trees

Passable Paths (easy version)

dfs and similar, trees

Permutation Restoration

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

River Locks

binary search, dp, greedy, math

Guess The String

binary search, constructive algorithms, interactive

Placing Jinas

combinatorics, math

Permutation Graph

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

Count the Trains

binary search, data structures, greedy, sortings

Lena and Matrix

data structures, dp, geometry, shortest paths

Linguistics

greedy, implementation, sortings, strings

MEX vs DIFF

binary search, brute force, constructive algorithms, data structures, greedy, two pointers

Circular Spanning Tree

constructive algorithms, implementation, trees

Moving Chips

bitmasks, dp, greedy

Toss a Coin to Your Graph...

binary search, dfs and similar, dp, graphs

Tokitsukaze and Two Colorful Tapes

constructive algorithms, dfs and similar, graphs, greedy

Remove Directed Edges

dfs and similar, dp, graphs

Breaking the Wall

binary search, brute force, constructive algorithms, greedy, math

Lost Arithmetic Progression

combinatorics, math, number theory

Array Shuffling

constructive algorithms, graphs, greedy

Preorder

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

Optimal Partition

data structures, dp

Job Lookup

constructive algorithms, dp, shortest paths, trees

GCD Guess

bitmasks, chinese remainder theorem, constructive algorithms, games, interactive, math, number theory

Progressions Covering

data structures, greedy

Promising String (hard version)

data structures, implementation, math, strings

Reverse Sort Sum

constructive algorithms, data structures, greedy, implementation, math, two pointers

For Gamers. By Gamers.

binary search, brute force, greedy, math, sortings

K-good

constructive algorithms, math, number theory

Potion Brewing Class

dfs and similar, math, number theory, trees

Nearest Excluded Points

binary search, data structures, dfs and similar, graphs, shortest paths

Counting Shortcuts

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

Rescheduling the Exam

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

Tyler and Strings

combinatorics, data structures, implementation

Madoka and the Best School in Russia

constructive algorithms, dp, math, number theory

Weight the Tree

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

Expand the Path

brute force, combinatorics, data structures, implementation, math

Repetitions Decoding

constructive algorithms, implementation, sortings

Big Brush

constructive algorithms, data structures, greedy, implementation

Best Pair

binary search, brute force, implementation

Finding Zero

constructive algorithms, interactive, math

New Year Concert

binary search, data structures, greedy, math, number theory, two pointers

Game on Sum (Easy Version)

combinatorics, dp, games, math

Not Adding

brute force, dp, math, number theory

Martial Arts Tournament

binary search, brute force, greedy, math

MinOr Tree

bitmasks, dfs and similar, dsu, graphs, greedy

Interacdive Problem

binary search, constructive algorithms, interactive

Masha-forgetful

brute force, constructive algorithms, dp, hashing, implementation, strings

Shuffle

combinatorics, math, two pointers

The Winter Hike

constructive algorithms, greedy, math

Replace the Numbers

constructive algorithms, data structures, dsu, implementation

Exact Change

brute force, constructive algorithms, greedy

Unusual Minesweeper

binary search, dfs and similar, dsu, greedy, sortings

Let's Play the Hat?

brute force, constructive algorithms, greedy, math

Reverse

bitmasks, constructive algorithms, dfs and similar, implementation, math, strings

Keep the Average High

dp, greedy, math

Divan and Kostomuksha (easy version)

dp, number theory

Crazy Robot

dfs and similar, graphs

MEX Sequences

dp, math

Messages

brute force, dp, greedy, probabilities, sortings

Escape The Maze (hard version)

dfs and similar, dp, greedy, shortest paths, trees

Not Quite Lee

combinatorics, dp, math, number theory

Arena

combinatorics, dp, math

Treelabeling

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

Frog Traveler

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

Array Game

games, greedy, two pointers

Hidden Fortress

interactive, math

Bubble Strike

combinatorics, math, probabilities, ternary search

Staircases

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

Red-Black Number

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

Half of Same

brute force, math, number theory

Yet Another Sorting Problem

data structures, math

Guess the Permutation

binary search, combinatorics, interactive, math

Pchelyonok and Segments

binary search, data structures, dp, greedy, math

Longest Array Deconstruction

data structures, divide and conquer, dp, sortings

The Strongest Build

binary search, brute force, data structures, dfs and similar, graphs, greedy, hashing, implementation