The Child and Binary Tree

combinatorics, divide and conquer, fft, number theory

The Child and Sequence

data structures, math

The Child and Polygon

dp, geometry

The Child and Zoo

dsu, sortings

Banners

brute force, data structures, dp

Cardboard Box

data structures, greedy

Pudding Monsters

dp

Dungeons and Candies

dsu, graphs, greedy, trees

Special Graph

Special Grid

brute force, dp, greedy

Cardiogram

implementation

Furukawa Nagisa's Tree

binary search, divide and conquer, sortings, trees

Nanami's Power Plant

flows

Tachibana Kanade's Tofu

dp

Nanami's Digital Board

dsu, implementation

Ryouko's Memory Note

implementation, math, sortings

Square Tiling

constructive algorithms, greedy

Prefixes and Suffixes

dp, string suffix structures, strings, two pointers

Prime Swaps

greedy, sortings

Chemistry Experiment

binary search, data structures, ternary search

Random Task

binary search, bitmasks, combinatorics, dp, math

k-Tree

dp, implementation, trees

Points and Segments (easy)

constructive algorithms, sortings

Points and Segments

graphs

Tricky Function

data structures, divide and conquer, geometry

Guess the Tree

bitmasks, constructive algorithms, dp, greedy, trees

Working out

dp

Police Patrol

greedy, implementation, math, ternary search

Match & Catch

dp, string suffix structures, strings

Checkposts

dfs and similar, graphs, two pointers

Sereja and Sets

dp

Sereja and Squares

binary search, data structures, hashing

Sereja and Two Sequences

data structures, dp

Sereja and Table

bitmasks, greedy

Colored Jenga

dfs and similar, dp, probabilities

Biathlon Track

binary search, brute force, constructive algorithms, data structures, dp

Magic Formulas

math

Bug in Code

binary search, data structures, sortings

Playing the ball

geometry

Cup Trick

data structures

Bug in Code

data structures, graphs, implementation, two pointers

Online Meeting

implementation

Tricky Password

data structures

Big Problems for Organizers

data structures, graphs, trees

Square Table

constructive algorithms, math, probabilities

Cunning Gena

bitmasks, dp, greedy, sortings

President's Path

dp, graphs, shortest paths

Population Size

greedy, implementation, math

Booking System

binary search, dp, greedy, implementation

Mashmokh's Designed Problem

data structures

Mashmokh and Water Tanks

binary search, data structures, greedy, trees, two pointers

Mashmokh and Reverse Operation

combinatorics, divide and conquer

Maze 2D

data structures, divide and conquer

2048

bitmasks, dp

E-mail Addresses

implementation

Giving Awards

dfs and similar

Kicker

implementation

Multi-core Processor

implementation

Feed the Golorp

*special problem

On a plane

*special problem, geometry

000001

*special problem

Dome

*special problem

Big Data

*special problem

Magnum Opus

*special problem

Mysterious Language

*special problem

The Great Game

*special problem

k-d-sequence

data structures

Largest Submatrix 3

dp, hashing

Curious Array

brute force, combinatorics, implementation, math

Long Path

dp, implementation

Triangle

brute force, geometry, implementation, math

Hamming Triples

implementation, math, two pointers

Hill Climbing

dfs and similar, geometry, trees

Graph Cutting

dfs and similar, graphs

Toy Sum

greedy, implementation, math

Unusual Product

implementation, math

Maze 1D

binary search, greedy, implementation

Minesweeper 1D

dp, implementation

Restore Graph

dfs and similar, graphs, sortings

Two Rooted Trees

data structures, implementation, trees

Beautiful Pairs of Numbers

combinatorics, dp

Strictly Positive Matrix

graphs, math

Upgrading Array

dp, greedy, math, number theory

Olympic Games

math

Roman and Numbers

bitmasks, brute force, combinatorics, dp, number theory

Inna and Binary Logic

binary search, bitmasks, data structures

Dima and Bacteria

dsu, graphs, shortest paths

Fox and Meteor Shower

geometry

Fox and Perfect Sets

math

Fox and Card Game

games, greedy, sortings

Fox and Minimal path

bitmasks, constructive algorithms, graphs, implementation, math

George and Cards

binary search, data structures

George and Interesting Graph

graph matchings

George and Number

greedy, implementation

Game with Points

dp, graphs, implementation, shortest paths

Diverse Substrings

dp, strings, two pointers

Bear in the Field

math, matrices

Bear and Floodlight

bitmasks, dp, geometry

Bear and Prime Numbers

binary search, brute force, data structures, dp, implementation, math, number theory

Vowels

combinatorics, divide and conquer, dp