Maze

dfs and similar, dp, probabilities, trees

Lucky Array

data structures

Lucky Segments

binary search, implementation, two pointers

Alternative Reality

geometry

String Transformation

hashing, strings

Tree or not Tree

data structures, divide and conquer, implementation, trees

Not Quick Transformation

divide and conquer, math

Linear Kingdom Races

data structures, dp

Unambiguous Arithmetic Expression

dp, expression parsing

Sleeping

combinatorics, implementation, math

Museum

math, matrices, probabilities

Petya and Rectangle

Lucky Interval

brute force, math

Darts

geometry, probabilities

Crime Management

dp, graphs, matrices

Arrangement

bitmasks, dp

Lift and Throw

brute force

Entertaining Geodetics

brute force, dsu, implementation

Buying Sets

flows, graph matchings

Candies and Stones

divide and conquer, dp

Interval Coloring

*special problem, greedy, math

Help Shrek and Donkey

dp, games, math, probabilities

Help Monks

constructive algorithms

Help Greg the Dwarf

geometry, ternary search

Robot in Basement

bitmasks, brute force, implementation

Winning Strategy

binary search, graphs, math, shortest paths

Domino

brute force, implementation

Lucky Country

dp, dsu, graphs

Horse Races

dp, math

Lostborn

dp, math, number theory

Flags

dp, math, matrices

Azembler

brute force, implementation

Igloo Skyscraper

data structures, geometry

Grocer's Problem

constructive algorithms, graphs, greedy

Fire and Ice

greedy

Space mines

geometry

Mogohu-Rea Idol

geometry

Long sequence

brute force, math, matrices

Genetic engineering

dp, string suffix structures, trees

Guard Towers

binary search, dsu, geometry, graphs, sortings

Two Subsequences

bitmasks, dp

Numbers

dp, math, number theory

Track

graphs, greedy, shortest paths

Corridor

geometry

Pairs

dfs and similar, dp, dsu, graphs, implementation, trees

Security System

math

Password

bitmasks, dp, shortest paths

Martian Food

geometry

Mutation

bitmasks, dp, math

Ship's Shortest Path

geometry, shortest paths

Shift It!

constructive algorithms

Hanger

data structures

Plane of Tanks

brute force, geometry

Morrowindows

math, number theory

Information Reform

dp, implementation, trees

Professor's task

data structures, geometry

Contact

geometry

Half-decay tree

data structures, divide and conquer, dp, math, probabilities

Save the City!

geometry

Sequence of Balls

dp

Harry Potter and Moving Staircases

dfs and similar, implementation

Sort the Table

*special problem, sortings

World Evil

dp, flows

Mushroom Gnomes

math, matrices

Savior

brute force, dsu, math

Expression

dp

Chess

math, shortest paths

Journey

dp, math

Very simple problem

geometry, two pointers

Beautiful numbers

dp, number theory

Vacuum Сleaner

geometry

Dead Ends

bitmasks, dp

Caterpillar

dfs and similar, dp, graphs, trees

Pentagon

combinatorics, graphs, matrices

Black and White

constructive algorithms

Galaxy Union

dp, trees, two pointers

Snow sellers

greedy, sortings

Emperor's Problem

geometry

Goats and Wolves

greedy

Shooting Gallery

data structures, implementation

BerPaint

geometry, graphs

Baldman and the military

dfs and similar, graphs, trees

Number Table

combinatorics

Interesting Sequence

math

Testing

Tram

Inverse Function

implementation

The Great Marathon

dp

Trial for Chief

graphs, greedy, shortest paths

Two Paths

constructive algorithms, dsu, graphs, implementation

Helper

Hide-and-Seek

geometry, implementation

TV Game

dp

Tricky and Clever Password

binary search, constructive algorithms, data structures, greedy, hashing, strings

King's Problem?

geometry, greedy

Quarrel

graphs, shortest paths

DravDe saves the world

geometry, math

Don't fear, DravDe is kind

binary search, data structures, dp, hashing

Multithreading

constructive algorithms

Tickets

combinatorics, math, probabilities