XOR Counting

bitmasks, combinatorics, dp, math

Divide, XOR, and Conquer

bitmasks, dp, math

Stranger Trees

dp, math, matrices, trees

Xor-matic Number of the Graph

bitmasks, graphs, math, number theory, trees

Parametric MST

binary search, constructive algorithms, graphs, greedy, math, sortings

Twin Clusters

bitmasks, brute force, constructive algorithms, math, probabilities

Positions in Permutations

combinatorics, dp, math

Destroy the Colony

combinatorics, dp, math

Omkar and Akmar

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

Mercenaries

bitmasks, brute force, combinatorics, dp, dsu, math, two pointers

Sum the Fibonacci

bitmasks, divide and conquer, dp, fft, math

Enormous XOR

bitmasks, constructive algorithms, greedy, math, strings, two pointers

Song of the Sirens

combinatorics, divide and conquer, hashing, math, string suffix structures, strings

Lamps on a Circle

games, implementation, interactive, math

Survival of the Weakest (easy version)

binary search, brute force, implementation, math, sortings

Tavas and Pashmaks

geometry, math

Random Walk

dp, graphs, math, probabilities, trees

Counting Prefixes

combinatorics, constructive algorithms, dp, implementation, math

Running Competition

bitmasks, fft, math, number theory

Circular Dungeon

greedy, math, probabilities

Serval and Bonus Problem

combinatorics, dp, math, probabilities

Conditional Mix

combinatorics, dp, math

Bingo

bitmasks, combinatorics, dp, math, probabilities

Number Challenge

combinatorics, dp, implementation, math, number theory

Vika and Stone Skipping

brute force, implementation, math, number theory

Min Cost Permutation (Easy Version)

brute force, constructive algorithms, greedy, math

Timber

combinatorics, dp, fft, math

Timofey and remoduling

brute force, implementation, math, number theory

Count Voting

combinatorics, dp, math

Winding polygonal line

constructive algorithms, geometry, greedy, math

Interval Cubing

data structures, math

Bracket Xoring

constructive algorithms, greedy, implementation, math

Fancy Arrays

combinatorics, dp, math, matrices

Yet Another DAG Problem

bitmasks, dfs and similar, dp, flows, graphs, math

Tree Sum

combinatorics, math, trees

Maximizing Root

dfs and similar, dp, graphs, math, number theory, trees

Strange Sorting

implementation, math

Divisor Set

divide and conquer, fft, greedy, math, number theory

Piglet's Birthday

dp, math, probabilities

Cutting Rectangle

brute force, math, number theory

Limak and Shooting Points

brute force, geometry, math

Formalism for Formalism

bitmasks, dp, math

Superhero's Job

dfs and similar, dp, hashing, math, number theory

Sum of Matchings

brute force, combinatorics, constructive algorithms, dfs and similar, graph matchings, greedy, math

GCD is Greater

brute force, data structures, math, number theory

Gifts

combinatorics, dp, math, probabilities

Lostborn

dp, math, number theory

Candies for Children

brute force, math

Visit of the Great

math, number theory

Upgrading Tree

constructive algorithms, dfs and similar, graphs, math, trees

Tetragon

geometry, math

Mushroom Gnomes

math, matrices

X-mouse in the Campus

bitmasks, math, number theory

Endless Matrix

math

Rotatable Number

math, number theory

Interesting Sequence

math

Subset with Zero Sum

constructive algorithms, dfs and similar, graphs, math

Power Tower

chinese remainder theorem, math, number theory

Fibonacci Additions

brute force, data structures, hashing, implementation, math

PermuTree (hard version)

bitmasks, dfs and similar, dp, fft, greedy, implementation, math, trees

Partitions

combinatorics, math, number theory

Latin Square

math, matrices

Cowmpany Cowmpensation

combinatorics, dp, math, trees

Conveyor

constructive algorithms, dp, math

Two Arrays

bitmasks, brute force, combinatorics, greedy, hashing, math, two pointers

Common Divisor Graph

brute force, constructive algorithms, dsu, graphs, hashing, math, number theory

Boring Queries

data structures, math, number theory

Résumé Review

binary search, greedy, math

Phoenix and Odometers

dfs and similar, graphs, math, number theory

Strange Set

flows, math

Mother of Dragons

brute force, graphs, math, meet-in-the-middle

Majority

combinatorics, dp, math, strings

Christmas Chocolates

dfs and similar, dp, games, graphs, implementation, math, number theory, shortest paths, trees

Nested Rubber Bands

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

Airplane Arrangements

math, number theory

Split

binary search, data structures, divide and conquer, dsu, math, trees, two pointers

Abnormal Permutation Pairs (hard version)

combinatorics, dp, fft, math

Rusty String

fft, math, strings

Johnny Solving

constructive algorithms, dfs and similar, graphs, math

Chaotic V.

dp, graphs, greedy, math, number theory, trees

Balanced Subsequences

combinatorics, dp, math

Fibonotci

data structures, math, matrices

Friends

binary search, bitmasks, data structures, math

Misha and Paintings

constructive algorithms, data structures, greedy, implementation, math

Bracket Insertion

combinatorics, dp, math, trees

Juju and Binary String

brute force, constructive algorithms, greedy, math

Nene vs. Monsters (Hard Version)

brute force, greedy, implementation, math

Museum

math, matrices, probabilities

Chiori and Doll Picking (easy version)

bitmasks, brute force, combinatorics, math

Converging Array (Easy Version)

dp, math

Matrix Rank (Easy Version)

brute force, combinatorics, dp, math, matrices

Bear and Destroying Subtrees

dp, math, probabilities, trees

No Game No Life

bitmasks, games, math, matrices

String Counting

combinatorics, dp, fft, math

Unordered Swaps

constructive algorithms, dfs and similar, graphs, greedy, math, sortings, trees

Farmer John's Favorite Function

brute force, data structures, implementation, math

Another n-dimensional chocolate bar

dp, math, meet-in-the-middle, number theory

Japanese Game

constructive algorithms, math

Crop Squares

constructive algorithms, geometry, interactive, math

Matrix Rank (Hard Version)

combinatorics, dp, math, matrices, string suffix structures