Reverse Card (Hard Version)

brute force, math, number theory

Carousel of Combinations

brute force, combinatorics, dp, math, number theory

GCD on a grid

brute force, dfs and similar, dp, implementation, math, number theory

Chain Reaction

binary search, data structures, dsu, greedy, implementation, math, number theory

Girl Permutation

combinatorics, dp, math, number theory

Moving Platforms

graphs, math, number theory, shortest paths

One-Dimensional Puzzle

combinatorics, math, number theory

Modular Sequence

brute force, constructive algorithms, dp, graphs, greedy, math, number theory

Yet Another Inversions Problem

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

Multiple Lamps

bitmasks, brute force, constructive algorithms, math, number theory

Split Plus K

greedy, math, number theory

Small GCD

bitmasks, brute force, dp, math, number theory

Counting Rhyme

dp, math, number theory

Vasilije Loves Number Theory

brute force, math, number theory

Ntarsis' Set

binary search, math, number theory

Vika and Price Tags

math, number theory

MEX of LCM

binary search, data structures, implementation, math, number theory

Hyperregular Bracket Strings

combinatorics, greedy, hashing, math, number theory, sortings

Magic Triples (Hard Version)

brute force, data structures, math, number theory

Gifts from Grandfather Ahmed

dp, math, number theory

Li Hua and Array

brute force, data structures, dsu, math, number theory, two pointers

Counting Factorizations

combinatorics, divide and conquer, dp, math, number theory

Serval and Music Game

brute force, dp, implementation, math, number theory

Game of the Year

brute force, data structures, math, number theory

Many Perfect Squares

brute force, math, number theory

Delicious Dessert

binary search, dsu, hashing, math, number theory, string suffix structures

Josuke and Complete Graph

binary search, brute force, data structures, math, number theory

Friendly Spiders

dfs and similar, graphs, math, number theory, shortest paths

Partial Sorting

combinatorics, math, number theory

Node Pairs

dp, graphs, math, number theory

Valid Bitonic Permutations

combinatorics, dp, implementation, math, number theory

All Possible Digits

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

Count GCD

combinatorics, math, number theory

Counting Arrays

combinatorics, dp, math, number theory

ConstructOR

bitmasks, chinese remainder theorem, combinatorics, constructive algorithms, math, number theory

Divisible Numbers (hard version)

brute force, math, number theory

Graph Cost

dp, greedy, math, number theory

Red-Black Pepper

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

Electrical Efficiency

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

Tonya and Burenka-179

data structures, greedy, math, number theory

Fibonacci Strings

greedy, implementation, math, number theory

Madoka and The Best University

math, number theory

Bags with Balls

combinatorics, dp, math, number theory

LCM Sum (hard version)

brute force, data structures, math, number theory, two pointers

LCM Sum (easy version)

binary search, brute force, combinatorics, math, number theory, two pointers

Chopping Carrots (Hard Version)

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

Power or XOR?

bitmasks, combinatorics, math, number theory

Lost Arithmetic Progression

combinatorics, math, number theory

GCD Guess

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

Gojou and Matrix Game

data structures, dp, games, hashing, implementation, math, number theory, sortings

K-good

constructive algorithms, math, number theory

Potion Brewing Class

dfs and similar, math, number theory, trees

Madoka and the Best School in Russia

constructive algorithms, dp, math, number theory

Power Board

brute force, dp, math, number theory

Infinite Set

bitmasks, dp, math, matrices, number theory, strings

New Year Concert

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

Not Adding

brute force, dp, math, number theory

Not Quite Lee

combinatorics, dp, math, number theory

Dominoes

combinatorics, fft, graphs, math, number theory

Array Equalizer

binary search, greedy, implementation, math, number theory, sortings, two pointers

Extreme Extension

dp, greedy, math, number theory

Half of Same

brute force, math, number theory

Hemose in ICPC ?

binary search, dfs and similar, implementation, interactive, math, number theory, trees

GCD Festival

math, number theory

Mocha and Stars

combinatorics, dp, fft, math, number theory

Up the Strip

brute force, dp, math, number theory, two pointers

Gregor and the Odd Cows (Easy)

bitmasks, geometry, math, number theory

Integers Have Friends

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

Digits

dp, math, number theory

Two chandeliers

binary search, brute force, chinese remainder theorem, math, number theory

The Number of Pairs

dp, math, number theory

Square-free division (hard version)

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

GCD of an Array

brute force, data structures, hashing, implementation, math, number theory, sortings, two pointers

Multiples and Power Differences

constructive algorithms, graphs, math, number theory

Nezzar and Board

constructive algorithms, math, number theory

Strange Beauty

dp, math, number theory, sortings

Strange Definition

bitmasks, graphs, hashing, math, number theory

Xum

bitmasks, constructive algorithms, math, matrices, number theory

Decryption

constructive algorithms, implementation, math, number theory

Maximum Distributed Tree

dfs and similar, dp, greedy, implementation, math, number theory, sortings, trees

Calendar Ambiguity

math, number theory

Asterism (Hard Version)

binary search, combinatorics, dp, math, number theory, sortings

Asterism (Easy Version)

binary search, brute force, combinatorics, math, number theory, sortings

Two Divisors

constructive algorithms, math, number theory

Modular Stability

combinatorics, math, number theory

Two IP Cameras

*special problem, math, number theory

Divisor Paths

combinatorics, graphs, greedy, math, number theory

Kate and imperfection

greedy, implementation, math, number theory, sortings, two pointers

Infinite Path

brute force, dfs and similar, graphs, math, number theory

Instant Noodles

graphs, hashing, math, number theory

Kuroni and the Punishment

math, number theory, probabilities

Same GCDs

math, number theory

Send Boxes to Alice (Hard Version)

constructive algorithms, greedy, math, number theory, ternary search, two pointers

Send Boxes to Alice (Easy Version)

constructive algorithms, greedy, math, number theory, ternary search, two pointers

The Football Season

brute force, math, number theory

Power Products

hashing, math, number theory

Alex and Julian

bitmasks, math, number theory

Kamil and Making a Stream

math, number theory, trees

Natasha, Sasha and the Prefix Sums

combinatorics, dp, math, number theory

Graph Traveler

brute force, data structures, dfs and similar, dp, graphs, implementation, math, number theory