Familiar Operations

brute force, graphs, math

Jackets and Packets

dp

Future Failure

dp, games

Polo the Penguin and Lucky Numbers

dp, implementation, math

Palindromic Problem

binary search, data structures, hashing, string suffix structures, strings

Alien DNA

data structures, dsu, trees

Sign Posts

brute force, geometry, math

Beautiful Tree

data structures, dfs and similar, graphs, implementation, trees

Perfect Matching

data structures, divide and conquer, interactive, trees

Scaygerboss

flows

AB-Strings

constructive algorithms, strings

Goblins And Gnomes

brute force, dp, flows, graph matchings

Pudding Monsters

dp

Game of Questions

bitmasks, combinatorics, dp, fft, math, probabilities

Building Forest Trails

data structures, dsu

Frog Fights

data structures, greedy

Google Code Jam

dp, probabilities

Anti-Tetris

constructive algorithms, graphs, shortest paths

Shrink-Reverse

binary search, brute force, greedy, hashing, implementation, string suffix structures, strings

Fading into Fog

geometry, interactive, math, probabilities

Teamwork

constructive algorithms, greedy, math

Tree nesting

combinatorics, graphs, trees

Kingdom of Islands

brute force, graphs, implementation

Forward, march!

binary search, dp, greedy

Road Repairs

dfs and similar, graphs, greedy

Swimmers in the Pool

dp, fft, math, number theory

Appleman and Complicated Task

dsu, math

Yaroslav and Arrangements

dp

Matching Reduction

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

Martian Food

geometry

Boolean Computer

bitmasks, brute force, fft, math

Bessie and Cards

combinatorics, dp, math

Min Cost Permutation (Hard Version)

binary search, constructive algorithms, data structures, greedy, math, sortings

Twilight and Ancient Scroll (easier version)

dp, hashing, implementation, string suffix structures, strings

Tournament Construction

constructive algorithms, dp, graphs, greedy, math

Red-Black Cobweb

data structures, divide and conquer, implementation, trees

Tiles Placement

constructive algorithms, dfs and similar, trees

DZY Loves Games

math, matrices, probabilities

Random Elections

bitmasks, brute force, divide and conquer, fft, math

Directing Edges

dfs and similar, dp, graphs, trees

Tiles

combinatorics, dp, fft, math

Inverse Genealogy

constructive algorithms, divide and conquer, dp, math, trees

Andrey's Tree

binary search, constructive algorithms, data structures, dfs and similar, dsu, greedy, implementation, trees

Design Tutorial: Increase the Constraints

bitmasks, data structures, fft

Nikita and game

binary search, dfs and similar, divide and conquer, graphs, trees

Delivery Oligopoly

brute force, dp, graphs

Maxim and Calculator

brute force, dp, two pointers

Long Way to be Non-decreasing

binary search, dfs and similar, graphs, implementation, shortest paths, two pointers

Letters and Question Marks

bitmasks, dp, string suffix structures

Speed Dial

dp, strings, trees

Weighed Tree Radius

data structures, divide and conquer, implementation, trees

Prediction

combinatorics, dp, math

Location

data structures, dp, math, number theory

Sherlock's bet to Moriarty

constructive algorithms, data structures, divide and conquer, geometry, graphs, implementation, trees

String and Operations

dp, greedy

Minibuses on Venus (hard version)

brute force, combinatorics, dp, math

Random Forest Rank

dp, graph matchings, math, trees

Robots protection

data structures

Permutation Weight (Easy Version)

constructive algorithms, dfs and similar, dsu

The Cells on the Paper

binary search, implementation, sortings

Randomizer

combinatorics, geometry, probabilities

Pilgrims

dfs and similar, dp, trees

Miriany and Matchstick

constructive algorithms, dp, greedy

Joker

*special problem, bitmasks, data structures, divide and conquer, dsu

Cookie Clicker

dp, geometry

Permutations

math, matrices

Two Subsequences

bitmasks, dp

Au Pont Rouge

binary search, dp, strings

Chess Strikes Back (hard version)

data structures, divide and conquer

Big Problems for Organizers

data structures, graphs, trees

Cyclic Cipher

chinese remainder theorem, data structures, implementation, number theory, two pointers

Last Man Standing

brute force, data structures, number theory

Distance to the Path

data structures, dfs and similar, trees

Bridge Club

flows, graph matchings, graphs, greedy

New Year and Finding Roots

constructive algorithms, implementation, interactive, trees

Foreigner

dp

Rain of Fire

binary search, data structures, dfs and similar, dsu, graphs, implementation

Vasya and Polynomial

math

Ehab and a weird weight formula

data structures, trees

Sum Over Subsets

combinatorics, math, number theory

Mister B and Flight to the Moon

constructive algorithms, graphs

BRT Contract

data structures

Coffee Varieties (easy version)

graphs, interactive

Travelling Through the Snow Queen's Kingdom

bitmasks, brute force, divide and conquer, graphs

Raging Thunder

data structures, divide and conquer, implementation

Parking Lot

data structures, divide and conquer

Too Many Constraints

2-sat, constructive algorithms, graphs, implementation

Number of Components

dsu, implementation

Tree Queries

brute force, dp, trees

Neko Rules the Catniverse (Small Version)

bitmasks, dp, matrices

Ants on a Circle

constructive algorithms, math

The Next Good String

data structures, greedy, hashing, strings

Nezzar and Hidden Permutations

constructive algorithms, dfs and similar, graphs

M-tree

data structures, math, sortings, trees

Caterpillar

dfs and similar, dp, graphs, trees

Swaps

combinatorics, dp, graphs, math

Armor and Weapons

brute force, dp, greedy, shortest paths

Bear and Paradox

binary search, greedy, math, sortings

Euclid Guess

constructive algorithms, flows, graph matchings, math, number theory

Cats on the Upgrade (hard version)

binary search, data structures, dfs and similar, graphs, trees