Gregor and the Pawn Game

dfs and similar, dp, flows, graph matchings, graphs, greedy, implementation

Gregor and Cryptography

math, number theory

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

Web of Lies

brute force, graphs, greedy

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

Air Conditioners

data structures, dp, implementation, shortest paths, sortings, two pointers

Co-growing Sequence

bitmasks, constructive algorithms, greedy

Pair Programming

greedy, two pointers

Alphabetical Strings

greedy, implementation, strings

Shortest Path with Obstacle

implementation, math

AquaMoon and Stolen String

interactive, math

AquaMoon and Two Arrays

brute force, greedy

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

AquaMoon and Strange Sort

sortings

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

Customising the Track

combinatorics, greedy, math

Exciting Bets

greedy, math, number theory

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

Plus and Multiply

constructive algorithms, math, number theory

Odd Set

math

Pleasant Pairs

brute force, implementation, math, number theory

Pretty Permutations

constructive algorithms, greedy, implementation

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

Great Graphs

constructive algorithms, graphs, greedy, shortest paths, sortings

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

Stable Groups

greedy, sortings

Love Song

dp, implementation, strings

Contest Start

combinatorics, geometry, greedy, math

Gift Set

binary search, greedy, math, ternary search

Interesting Function

binary search, dp, math, number theory

Funny Substrings

data structures, hashing, implementation, matrices, strings

Another Problem About Dividing Numbers

constructive algorithms, math, number theory

Number of Pairs

binary search, data structures, math, two pointers

Friends and Candies

greedy, math

Stone Game

brute force, dp, greedy

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

Challenging Cliffs

constructive algorithms, greedy, implementation, math

Bad Boy

constructive algorithms, greedy, math

Arithmetic Array

greedy, math

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

Diluc and Kaeya

data structures, dp, hashing, number theory

Prinzessin der Verurteilung

brute force, constructive algorithms, strings

Omkar and Bad Story

brute force, constructive algorithms

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

Unstable String

binary search, dp, greedy, implementation, strings, two pointers

Array Reodering

brute force, greedy, math, number theory, sortings

Fair Playoff

brute force, implementation

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

Little Alawn's Puzzle

combinatorics, dp, dsu, graphs, math

Histogram Ugliness

greedy, implementation, math

Colour the Flag

brute force, implementation

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

Pursuit

binary search, brute force, greedy, sortings

Putting Plates

constructive algorithms, implementation

Binary Decimal

greedy, math

Sifid and Strange Subsequences

greedy, math, sortings

Eshag Loves Big Arrays

constructive algorithms, 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