Superstitions Inspection

*special problem

Black Cat Rush

*special problem

Chain Letter

*special problem, dfs and similar, graphs

Counting Fridays

*special problem

Triskaidekaphobia

*special problem

Expecting Trouble

*special problem, probabilities

Simple Molecules

brute force, graphs, math

Magnets

implementation

Pumping Stations

brute force, dfs and similar, divide and conquer, flows, graphs, greedy, trees

Water Tree

data structures, dfs and similar, graphs, trees

Read Time

binary search, greedy, two pointers

Alternating Current

data structures, greedy, implementation

Rational Resistance

math, number theory

Xenia and Tree

data structures, divide and conquer, trees

Xenia and Dominoes

bitmasks, dfs and similar, dp

Cupboard and Balloons

geometry

Xenia and Spies

brute force, greedy, implementation

Xenia and Divisors

greedy, implementation

Candies Game

constructive algorithms, greedy

Iahub and Xors

data structures

Iahub and Permutations

combinatorics, math

Bubble Sort Graph

binary search, data structures, dp

Tourist Problem

combinatorics, implementation, math

Maximal Area Quadrilateral

brute force, geometry

The Wall

math

Three Swaps

constructive algorithms, dfs and similar, greedy

Xenia and Bit Operations

data structures, trees

Xenia and Weights

constructive algorithms, dfs and similar, dp, graphs, greedy, shortest paths

Xenia and Ringroad

implementation

Helpful Maths

greedy, implementation, sortings, strings

Optimize!

data structures

GCD Table

chinese remainder theorem, math, number theory

Divisor Tree

brute force, number theory, trees

Book of Evil

dfs and similar, divide and conquer, dp, trees

Quiz

binary search, greedy, math, matrices, number theory

Routine Problem

greedy, math, number theory

Puzzles

greedy

Vasily the Bear and Painting Square

bitmasks, combinatorics, dp, implementation

Vasily the Bear and Beautiful Strings

combinatorics, math, number theory

Vasily the Bear and Sequence

brute force, greedy, implementation, number theory

Vasily the Bear and Fly

math

Vasily the Bear and Triangle

implementation, math

Buy One, Get One Free

dp, greedy

Counting Skyscrapers

dp, math, probabilities

Rectangles and Square

brute force, dp

More Reclamation

games

Palindrome

constructive algorithms, dp

Banana

binary search, constructive algorithms, greedy

Eight Point Sets

sortings

Candy Bags

implementation

Summer Earnings

binary search, bitmasks, brute force, geometry, sortings

Characteristics of Rectangles

binary search, bitmasks, brute force, implementation, sortings

Lucky Tickets

brute force, constructive algorithms

Chips

greedy

Secrets

greedy

Binary Key

dp, greedy, implementation

Theft of Blueprints

graphs, math

Students' Revenge

data structures, greedy, sortings

Maximum Absurdity

data structures, dp, implementation

Down the Hatch!

implementation

Deja Vu

constructive algorithms, dp

Deja Vu

constructive algorithms, graphs, implementation

Escaping on Beaveractor

data structures, implementation, trees

Escaping on Beaveractor

graphs

Escaping on Beaveractor

dfs and similar, implementation

The Great Julya Calendar

dp

The Great Julya Calendar

dp

The Great Julya Calendar

dp

Shave Beaver!

data structures

Shave Beaver!

implementation

Oh Sweet Beaverette

data structures, sortings

Oh Sweet Beaverette

brute force, implementation

Road Construction

constructive algorithms, graphs

Cakeminator

brute force, implementation

Evil

math

The Evil Temple and the Moving Rocks

constructive algorithms

Graph Reconstruction

constructive algorithms

Biridian Forest

dfs and similar, shortest paths

Purification

constructive algorithms, greedy

Sheldon and Ice Pieces

greedy

IQ Test

implementation

Axis Walking

bitmasks, combinatorics, constructive algorithms, dp, meet-in-the-middle

Block Tower

constructive algorithms, dfs and similar, graphs

Magic Five

combinatorics, math

Hungry Sequence

math

Flipping Game

brute force, dp, implementation

The Red Button

combinatorics, dfs and similar, dsu, graphs, greedy

Reclamation

dsu

Monsters and Diamonds

dfs and similar, graphs, shortest paths

Stadium and Games

binary search, math

Square and Rectangles

implementation

Two permutations

data structures

Tournament-graph

constructive algorithms, graphs

Black-and-White Cube

combinatorics, constructive algorithms

Ciel and Flowers

combinatorics, math

Ciel and Dancing

greedy

Ciel and Gondolas

data structures, divide and conquer, dp

Ciel and Flipboard

dp, greedy, math

Ciel the Commander

constructive algorithms, dfs and similar, divide and conquer, greedy, trees

Ciel and Duel

dp, flows, greedy