Even Subarrays

bitmasks, brute force, hashing, math, number theory

Kill Demodogs

greedy, math

Joey Takes Money

greedy, math

Almost Sorted

bitmasks, data structures, dp

Maximums and Minimums

combinatorics, data structures, divide and conquer, number theory

Prefixes and Suffixes

constructive algorithms, strings, two pointers

Minimum Notation

data structures, greedy, math, sortings

Meeting on the Line

binary search, geometry, greedy, implementation, math, ternary search

Planets

data structures, greedy, sortings

Cut Substrings

combinatorics, dp, hashing, strings, two pointers

Kirei and the Linear Function

hashing, math

Guess the Cycle Size

interactive, probabilities

Friends and the Restaurant

greedy, sortings, two pointers

Jumping on Tiles

constructive algorithms, strings

Decode String

greedy, strings

Two Elevators

math

Illumination

binary search, bitmasks, brute force, combinatorics, dp, math, two pointers

Fishermen

flows, graph matchings, greedy

Red-Black Pepper

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

Letter Picking

constructive algorithms, dp, games, two pointers

Digital Logarithm

data structures, greedy, sortings

Best Permutation

constructive algorithms, greedy

Colored Balls: Revisited

brute force, greedy, implementation, sortings

Mainak and the Bleeding Polygon

binary search, geometry, implementation, math

A Certain Magical Party

combinatorics, data structures, greedy, sortings

Late For Work (submissions are not allowed)

data structures, greedy, schedules, shortest paths

Almost Perfect

combinatorics, fft, math

Edge Split

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

Jatayu's Balanced Bracket Sequence

data structures, dsu, graphs, greedy

Mainak and Interesting Sequence

bitmasks, constructive algorithms, math

Mainak and Array

greedy, math

Moving Both Hands

dp, graphs, shortest paths

Lemper Cooking Competition

data structures

Kingdom of Criticism

data structures, dsu

Journey

dp, trees

Imitating the Key Tree

combinatorics, dsu, trees

Hot Black Hot White

constructive algorithms, math

Garage

binary search, geometry, math

Field Photography

bitmasks, data structures, sortings

Electrical Efficiency

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

Deducing Sortability

binary search, bitmasks, math

Circular Mirror

binary search, combinatorics, geometry, math, two pointers

Basketball Together

binary search, greedy, sortings

Accumulation of Dominoes

math

Even-Odd XOR

bitmasks, constructive algorithms, greedy

L-shapes

dfs and similar, implementation

Counting Rectangles

brute force, data structures, dp, implementation

Line

greedy, sortings

Word Game

data structures, implementation

Colourblindness

implementation

Spell Check

implementation

Matching Reduction

brute force, constructive algorithms, dfs and similar, flows, graph matchings, graphs, interactive

Prefix Function Queries

dfs and similar, dp, hashing, string suffix structures, strings, trees

Maximum AND

bitmasks, dfs and similar, divide and conquer, greedy, sortings

Min-Max Array Transformation

binary search, greedy, two pointers

Deadly Laser

implementation

Image

greedy, implementation

Misha and Paintings

constructive algorithms, data structures, greedy, implementation, math

Xor-Subsequence (hard version)

bitmasks, data structures, dp, strings, trees

Xor-Subsequence (easy version)

bitmasks, brute force, dp, strings, trees, two pointers

Corners

greedy, implementation

Interesting Sum

brute force, data structures, greedy, math, sortings

Burenka Plays with Fractions

math, number theory

Fighting Tournament

binary search, data structures, implementation, two pointers

Mathematical Circus

constructive algorithms, math

Chip Game

games, math

Burenka, an Array and Queries

data structures, math, number theory

Impressionism

constructive algorithms, graphs, implementation, math

Permutation for Burenka

data structures, graph matchings, greedy, math, trees

Tonya and Burenka-179

data structures, greedy, math, number theory

Fibonacci Strings

greedy, implementation, math, number theory

Burenka and Traditions (hard version)

data structures, dp, greedy

Burenka and Traditions (easy version)

dp, greedy

Madoka and The First Session

constructive algorithms, flows, graph matchings, graphs, implementation

Madoka and The Best University

math, number theory

Madoka and The Corruption Scheme

combinatorics, constructive algorithms, greedy, math

Madoka and Formal Statement

greedy

Madoka and Underground Competitions

constructive algorithms, implementation

Madoka and Strange Thoughts

math, number theory

Bags with Balls

combinatorics, dp, math, number theory

Swap and Maximum Block

bitmasks, data structures, dfs and similar, divide and conquer, dp

Chip Move

brute force, dp, math

Robot in a Hallway

data structures, dp, greedy, implementation, ternary search

Permutation Chain

constructive algorithms, math

2-3 Moves

greedy, math

Crop Squares

constructive algorithms, geometry, interactive, math

Long Way Home

data structures, divide and conquer, dp, geometry, graphs, greedy, shortest paths

2+ doors

2-sat, bitmasks, graphs, greedy

Monoblock

combinatorics, data structures, implementation, math

Beautiful Array

constructive algorithms, greedy, math

Crossmarket

constructive algorithms, greedy, math

Path Prefixes

binary search, data structures, dfs and similar, trees

Build a Tree and That Is It

constructive algorithms, implementation, trees

Add Modulo 10

brute force, math, number theory

Color with Occurrences

brute force, data structures, dp, greedy, strings

Minimum Varied Number

greedy

Remove Prefix

data structures, greedy, implementation

Everyone Loves to Sleep

implementation, math

Lost Array

bitmasks, combinatorics, constructive algorithms, dp, math

Cross Swapping

2-sat, data structures, dsu, greedy, matrices