Egg Roulette

bitmasks, brute force, divide and conquer, math, meet-in-the-middle

Keep talking and nobody explodes -- easy

bitmasks, brute force, expression parsing

Submatrices

*special problem, bitmasks, data structures, dp

Mateusz and an Infinite Sequence

bitmasks, brute force, dp, strings

Lookup Tables

bitmasks

Vasily the Bear and Painting Square

bitmasks, combinatorics, dp, implementation

Deducing Sortability

binary search, bitmasks, math

Hex Dyslexia

bitmasks, brute force, dp, graphs

Good Graph

bitmasks, dfs and similar, graph matchings, graphs, implementation

Bugaboo

bitmasks, constructive algorithms, dp, number theory

Four Suits

binary search, bitmasks, flows, greedy

Code Lock

bitmasks, dp

Sequence Recovery

bitmasks, data structures, greedy

Phoenix and Bits

bitmasks, brute force, data structures, sortings

Party

bitmasks, brute force, graph matchings

Cheat and Win

bitmasks, data structures, games, trees

Communism

bitmasks, dp, trees

Robot in Basement

bitmasks, brute force, implementation

Antifibonacci Cut

bitmasks, combinatorics, constructive algorithms, data structures, dp, hashing, math

Bitonix' Patrol

bitmasks, brute force, combinatorics, dfs and similar, math

Appropriate Team

bitmasks, math, number theory

Mutation

bitmasks, dp, math

Tree Cutting

bitmasks, dfs and similar, dp

Feeling Good

bitmasks, data structures

Chiori and Doll Picking (hard version)

bitmasks, brute force, combinatorics, math

Bob's Beautiful Array

bitmasks, brute force, greedy

X-mouse in the Campus

bitmasks, math, number theory

Nora's Toy Boxes

bitmasks, combinatorics, dp

Misha and XOR

bitmasks

Dark Matter

bitmasks, geometry

Long Binary String

bitmasks, math, matrices, meet-in-the-middle, number theory

Gates to Another World

bitmasks, data structures, dsu, two pointers

Game of Questions

bitmasks, combinatorics, dp, fft, math, probabilities

Fix the String

*special problem, bitmasks, dp, greedy

Polycarpus is Looking for Good Substrings

bitmasks, hashing, implementation

Circular Xor Reversal

bitmasks, constructive algorithms

Sherlock and the Encrypted Data

bitmasks, combinatorics, dp

Matvey's Birthday

bitmasks, graphs

Substring Search

bitmasks, brute force, fft

Sources and Sinks

bitmasks, brute force, dfs and similar

Arrangement

bitmasks, dp

Boolean Computer

bitmasks, brute force, fft, math

Xor-Set

bitmasks, divide and conquer, math

Enchanted Matrix

bitmasks, interactive, number theory

Random Elections

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

Chests and Keys

bitmasks, brute force, dfs and similar, dp, flows

Illumination

binary search, bitmasks, brute force, combinatorics, dp, math, two pointers

Brand New Problem

bitmasks, brute force, dp

Design Tutorial: Increase the Constraints

bitmasks, data structures, fft

The Final Pursuit

bitmasks, constructive algorithms, divide and conquer, graphs, greedy, math

Favorite Game

bitmasks, dp

Professional layer

bitmasks, dp

Bitwise Paradox

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

Letters and Question Marks

bitmasks, dp, string suffix structures

Almost Sorted

bitmasks, data structures, dp

Around the World

bitmasks, combinatorics, dfs and similar, dp, graphs, graphs, math, trees

Guards In The Storehouse

bitmasks, dp

Joker

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

Gambling Nim

bitmasks, math, matrices, probabilities

Simplified Nonogram

bitmasks, dp, hashing, meet-in-the-middle

New Year and Binary Tree Paths

bitmasks, brute force, combinatorics, dp

Omkar and Pies

bitmasks, dfs and similar, dp, math, shortest paths

Two Sets

bitmasks, math

A Serious Referee

bitmasks, brute force, dfs and similar, sortings

Game with Strings

bitmasks, dp, games

Two Subsequences

bitmasks, dp

Button Pressing

bitmasks, constructive algorithms, hashing

Wise Men (Hard Version)

bitmasks, dp, math

Garden

bitmasks, dp, graphs, trees

Erasing Substrings

bitmasks, dp, greedy

Circling Round Treasures

bitmasks, shortest paths

Boolean Function

bitmasks, dp, expression parsing

Dasha and cyclic table

bitmasks, brute force, fft, strings, trees

Xenia and Dominoes

bitmasks, dfs and similar, dp

Formalism for Formalism

bitmasks, dp, math

Travelling Through the Snow Queen's Kingdom

bitmasks, brute force, divide and conquer, graphs

Lost Array

bitmasks, combinatorics, constructive algorithms, dp, math

Keyboard Design

bitmasks, data structures, dp, string suffix structures, strings

Neko Rules the Catniverse (Small Version)

bitmasks, dp, matrices

Serval and Brain Power

bitmasks, brute force, dp, greedy, implementation, strings

Crisp String

bitmasks, dp

Graph And Numbers

bitmasks, brute force, combinatorics, dp, meet-in-the-middle

To Make 1

bitmasks, constructive algorithms, dp, greedy, number theory

Multiset of Strings

bitmasks, brute force, dp, fft, flows, graphs, math, meet-in-the-middle, trees

Max Correct Set

bitmasks, dp, math

Tenzing and Random Real Numbers

bitmasks, dp, graphs, math, probabilities

String Transformation 2

bitmasks, dp, graphs, trees

MST with Matching

bitmasks, brute force, dsu, graph matchings, trees

Varying Kibibits

bitmasks, dp

Mark and the Online Exam

bitmasks, constructive algorithms, interactive, probabilities

No Game No Life

bitmasks, games, math, matrices

Little C Loves 3 III

bitmasks, dp, math

Neko Rules the Catniverse (Large Version)

bitmasks, dp, matrices

Maximize the Difference

bitmasks, brute force, dfs and similar

Koxia and Sequence

bitmasks, combinatorics, dp, math, number theory

Restoring Map

bitmasks, constructive algorithms, trees

Yet Another DAG Problem

bitmasks, dfs and similar, dp, flows, graphs, math

Sandy and Nuts

bitmasks, dp, trees

Sereja and Sets

bitmasks, dfs and similar

XOR Partition

binary search, bitmasks, data structures, divide and conquer, greedy, trees