Permutation Shift

brute force, combinatorics, constructive algorithms, dfs and similar, dsu, graphs, math

Organizing a Music Festival

dfs and similar, math

Guess the Perimeter

binary search, interactive, number theory

A Serious Referee

bitmasks, brute force, dfs and similar, sortings

Telepanting

binary search, data structures, dp, sortings

Colors and Intervals

constructive algorithms, data structures, greedy, sortings

Array Differentiation

bitmasks, brute force, constructive algorithms, dfs and similar, dp, graphs, math

Maximize the Intersections

combinatorics, constructive algorithms, geometry, greedy, sortings

Equidistant Vertices

brute force, combinatorics, dfs and similar, dp, trees

Fixed Points

binary search, brute force, dp

Domino (hard version)

constructive algorithms, implementation, math

Domino (easy version)

constructive algorithms, math

Jumping Around

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

Stringforces

binary search, bitmasks, brute force, dp, strings, two pointers

Excellent Arrays

binary search, combinatorics, constructive algorithms, implementation, math, sortings, two pointers

Manhattan Subarrays

brute force, geometry, greedy, implementation

Gregor and the Two Painters

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

Gregor and the Odd Cows (Hard)

brute force, geometry, math, number theory

Gregor and the Odd Cows (Easy)

bitmasks, geometry, math, number theory

The Three Little Pigs

combinatorics, dp, fft, math

Integers Have Friends

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

How Many Paths?

dfs and similar, dp, graphs, trees

Array Stabilization (GCD version)

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

AquaMoon and Potatoes

brute force, data structures, dp

AquaMoon and Time Stop (hard version)

data structures, dp

AquaMoon and Time Stop (easy version)

data structures, dp

AquaMoon and Wrong Coordinate

constructive algorithms, interactive, math

AquaMoon and Permutations

2-sat, brute force, combinatorics, constructive algorithms, graph matchings, graphs

AquaMoon and Chess

combinatorics, math

The Final Pursuit

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

RPD and Rap Sheet (Hard Version)

brute force, constructive algorithms, interactive, math

RPD and Rap Sheet (Easy Version)

bitmasks, constructive algorithms, interactive, math

Need for Pink Slips

bitmasks, brute force, dfs and similar, implementation, math, probabilities

Abnormal Permutation Pairs (hard version)

combinatorics, dp, fft, math

Abnormal Permutation Pairs (easy version)

combinatorics, dp, fft, math

Priority Queue

combinatorics, dp, implementation, math, ternary search

Strange Function

math, number theory

Tasty Dishes

math, matrices

Inverse Inversions

binary search, brute force, data structures

Converging Array (Hard Version)

dp, math

Converging Array (Easy Version)

dp, math

Tree Array

brute force, combinatorics, dp, graphs, math, probabilities, trees

Strange Array

data structures, greedy, sortings

Game with Cards

binary search, constructive algorithms, data structures, dp, greedy, implementation

PriceFixed

binary search, greedy, implementation, sortings, two pointers

Gift Set

binary search, greedy, math, ternary search

Funny Substrings

data structures, hashing, implementation, matrices, strings

Another Problem About Dividing Numbers

constructive algorithms, math, number theory

Figure Fixing

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

Erase and Extend (Hard Version)

binary search, data structures, greedy, hashing, string suffix structures, strings, two pointers

Erase and Extend (Easy Version)

binary search, brute force, dp, greedy, hashing, implementation, string suffix structures, strings, two pointers

Deleting Divisors

games, math, number theory

Omkar and Akmar

chinese remainder theorem, combinatorics, constructive algorithms, fft, games, geometry, math, meet-in-the-middle, string suffix structures

Omkar and Forest

combinatorics, graphs, math, shortest paths

Omkar and Medians

data structures, greedy, implementation

String Distance

binary search, brute force, data structures, hashing, implementation, strings

Gold Transfer

binary search, data structures, dp, greedy, interactive, trees

Playoff Tournament

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

Lost Nodes

constructive algorithms, dp, graphs, interactive, sortings, trees

A New Beginning

data structures, dp, geometry, sortings

Falling Sand (Hard Version)

dfs and similar, dp, graphs, greedy

Falling Sand (Easy Version)

dfs and similar, graphs, greedy

Lost Array

graphs, greedy, interactive, shortest paths

Lost Tree

constructive algorithms, interactive, trees

Turing's Award

data structures, dp

What a Reversal

constructive algorithms

Bingo

bitmasks, combinatorics, dp, math, probabilities

Minimax

constructive algorithms, greedy, strings

Secret Santa

constructive algorithms, flows, graphs, greedy, math

AmShZ Farm

combinatorics, fft, math

Mashtali and Hagh Trees

combinatorics, dp, trees

It's a bird! No, it's a plane! No, it's AaParsa!

constructive algorithms, graphs, shortest paths

Trees of Tranquillity

data structures, dfs and similar, greedy, trees

Kavi on Pairing Duty

combinatorics, dp, math

Parsa's Humongous Tree

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

Partition Game

binary search, data structures, divide and conquer, dp

MEX Tree

combinatorics, dfs and similar, implementation, math, trees

Sequence Pair Weight

hashing, implementation, math

Palindrome Game (hard version)

constructive algorithms, games

Median Queries

constructive algorithms, interactive, probabilities

Oolimry and Suffix Array

combinatorics, constructive algorithms, math

Kill Anton

brute force, constructive algorithms, data structures, math, strings

Potions (Hard Version)

data structures, greedy

Goblins And Gnomes

brute force, dp, flows, graph matchings

Assimilation IV

combinatorics, dp, math, probabilities, two pointers

Armchairs

dp, flows, graph matchings, greedy

Robot Collisions

data structures, greedy, implementation, sortings

Hopping Around the Array

data structures, dp

Try Booking

data structures, divide and conquer

Favorite Game

bitmasks, dp

Crypto Lights

combinatorics, dp, math, probabilities

Love-Hate

bitmasks, brute force, dp, probabilities

Compression and Expansion

brute force, data structures, greedy, implementation, trees

Nastia and a Beautiful Matrix

binary search, constructive algorithms, dp, greedy

Nastia Plays with a Tree

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

Nastia and a Hidden Permutation

constructive algorithms, interactive

To Go Or Not To Go?

brute force, dfs and similar, graphs, greedy, implementation, shortest paths

Guess the K-th Zero (Hard version)

binary search, constructive algorithms, data structures, interactive

Guess the K-th Zero (Easy version)

binary search, interactive

Chests and Keys

bitmasks, brute force, dfs and similar, dp, flows