A Serious Referee

bitmasks, brute force, dfs and similar, sortings

The Majestic Brown Tree Snake

dfs and similar, dp, greedy, trees, two pointers

LuoTianyi and the Function

data structures

Birthday

constructive algorithms, greedy, math

Array Game

data structures, games

Mike and code of a permutation

constructive algorithms, data structures, graphs, sortings

Buy One, Get One Free

dp, greedy

Little Pony and Elements of Harmony

dp, matrices

AquaMoon and Wrong Coordinate

constructive algorithms, interactive, math

Graph Game

graphs

Boolean Function

bitmasks, dp, expression parsing

...Wait for it...

data structures, dsu, trees

Mashtali: a Space Oddysey

constructive algorithms, dfs and similar, graphs

Doremy's Perfect DS Class (Medium Version)

binary search, interactive

Julia the snail

data structures, divide and conquer, dp

Game of Stacks

brute force, dfs and similar, graphs, implementation, trees

Falling Sand (Hard Version)

dfs and similar, dp, graphs, greedy

Mod Mod Mod

binary search, dp, math

Michael and Hotel

binary search, interactive, trees

Swap Pass

constructive algorithms, geometry, sortings

Guess the number

dp, interactive

Orchestra

two pointers

Empty Rectangles

divide and conquer, two pointers

Black, White and Grey Tree

binary search, constructive algorithms, dfs and similar, dp, greedy, trees

Tenzing and Random Real Numbers

bitmasks, dp, graphs, math, probabilities

Longest Increasing Subsequence

data structures, dp

Partial Virtual Trees

combinatorics, dfs and similar, dp, math, trees

Neko Rules the Catniverse (Large Version)

bitmasks, dp, matrices

Lucky Numbers (Hard Version)

dp, greedy

Artistic Partition

divide and conquer, dp, number theory

Olha and Igor

interactive, probabilities, trees

Lanterns

binary search, data structures, dp

Treeland and Viruses

data structures, dfs and similar, dp, shortest paths, trees

Centroid Probabilities

combinatorics, dp, fft, math

James and the Chase

dfs and similar, graphs, probabilities, trees

Game Relics

math, probabilities

Ping-Pong

data structures

Tree Weights

bitmasks, constructive algorithms, data structures, dfs and similar, implementation, math, matrices, number theory, trees

Vladislav and a Great Legend

combinatorics, dp, trees

Abandoning Roads

brute force, dp, graphs, greedy

Make It Ascending

bitmasks, brute force, dp

Coffee Varieties (hard version)

constructive algorithms, graphs, interactive

ZS Shuffles Cards

combinatorics, dp, math, probabilities

Quick Tortoise

bitmasks, divide and conquer, dp

Mr. Kitayuta's Gift

combinatorics, dp, matrices, strings

Logistical Questions

dfs and similar, divide and conquer, trees

Keep XOR Low

bitmasks, combinatorics, data structures, divide and conquer, dp, math

Freezing with Style

binary search, data structures, divide and conquer, trees

Indecisive Taxi Fee

data structures, graphs, shortest paths

Points and Segments

graphs

Lust

combinatorics, math, matrices

Gerald and Path

dp, sortings

Misha and LCP on Tree

binary search, dfs and similar, hashing, string suffix structures, trees

Duff is Mad

data structures, strings

Sergey's problem

constructive algorithms, graphs

Good Subsegments

data structures

Pastoral Oddities

data structures, divide and conquer, dsu, math, trees

Frequency Problem (Hard Version)

data structures, greedy, two pointers

The Classic Problem

data structures, graphs, shortest paths

Double Knapsack

constructive algorithms, two pointers

Substrings in a String

bitmasks, brute force, data structures, string suffix structures, strings

Gosha is hunting

brute force, data structures, dp, flows, math, probabilities, sortings

Pudding Monsters

data structures, divide and conquer

University Schedule

*special problem

BuberPool Taxi Optimization

*special problem, interactive

Two Colors

*special problem

Cyclic Shifts

*special problem, strings

Pac-Man 2.0

*special problem, dp

Laser Beams

*special problem, geometry, probabilities

Petya and Rectangle

Contact

geometry

Plane of Tanks

brute force, geometry

Pills

brute force, flows

Harry Potter and Moving Staircases

dfs and similar, implementation

Linearization

graphs

Icicles

Heaven Tour

data structures, greedy

Fire and Ice

greedy

Birthday

geometry, math

Jumbled Trees

constructive algorithms, math

Roads

*special problem, geometry, sortings

Finding Expected Value

math

Function Composition

dfs and similar

Deducing Sortability

binary search, bitmasks, math

Mixture

*special problem, data structures, geometry, math, sortings

Security System

math

Viruses

*special problem, dp, shortest paths, string suffix structures

Contingency Plan 2

graph matchings

Knightmare (easy)

graphs, interactive, shortest paths

Last Number

combinatorics, math

Candy Shop

greedy

Late For Work (submissions are not allowed)

data structures, greedy, schedules, shortest paths

Landscaping

binary search, geometry, two pointers

Grid Game 2

games, number theory

Restore the Tree

graphs, greedy, trees

Framing Pictures

geometry

Deja Vu

constructive algorithms, graphs, implementation

Hellish Constraints

brute force, dp, two pointers

Strange Triples

brute force, math, number theory

Chess Championship

constructive algorithms, flows, greedy, math