Sum the Fibonacci

bitmasks, divide and conquer, dp, fft, math

Substrings in a String

bitmasks, brute force, data structures, string suffix structures, strings

Palindromes in a Tree

bitmasks, data structures, divide and conquer, trees

Logical Expression

bitmasks, dp, shortest paths

Party Lemonade

bitmasks, dp, greedy

New Year's Eve

bitmasks, constructive algorithms, number theory

New Year and Entity Enumeration

bitmasks, combinatorics, dp, math

Party

bitmasks, brute force, dp, graphs

Clear The Matrix

bitmasks, dp

Unusual Sequences

bitmasks, combinatorics, dp, math, number theory

Square Subsets

bitmasks, combinatorics, dp, math

Xor-MST

bitmasks, constructive algorithms, data structures

Maximum Subsequence

bitmasks, divide and conquer, meet-in-the-middle

Magic Breeding

bitmasks

Short Program

bitmasks, constructive algorithms

Danil and a Part-time Job

bitmasks, data structures, trees

High Cry

binary search, bitmasks, combinatorics, data structures, divide and conquer

Huge Strings

bitmasks, brute force, dp, implementation, strings

Qualification Rounds

bitmasks, brute force, constructive algorithms, dp

Egg Roulette

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

Hex Dyslexia

bitmasks, brute force, dp, graphs

Salazar Slytherin's Locket

bitmasks, dp

Random Elections

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

Arpa and a game with Mojtaba

bitmasks, dp, games

Guards In The Storehouse

bitmasks, dp

Choosing The Commander

bitmasks, data structures, trees

Sagheer, the Hausmeister

bitmasks, brute force, dp

Coprime Subsequences

bitmasks, combinatorics, number theory

Sequence Recovery

bitmasks, data structures, greedy

Paths in a Complete Binary Tree

bitmasks, trees

Axel and Marston in Bitland

bitmasks, dp, graphs, matrices

Bitwise Formula

bitmasks, brute force, dfs and similar, expression parsing, implementation

Sherlock and the Encrypted Data

bitmasks, combinatorics, dp

Varying Kibibits

bitmasks, dp

k-Interesting Pairs Of Integers

*special problem, bitmasks, brute force, meet-in-the-middle

Game of Stones

bitmasks, dp, games

Mahmoud and a xor trip

bitmasks, constructive algorithms, data structures, dfs and similar, dp, math, trees

Felicity's Big Secret Revealed

bitmasks, dp

PolandBall and Gifts

bitmasks, dp, greedy

Dasha and cyclic table

bitmasks, brute force, fft, strings, trees

New Year and Binary Tree Paths

bitmasks, brute force, combinatorics, dp

Hongcow Buys a Deck of Cards

bitmasks, brute force, dp

Hongcow's Game

bitmasks, divide and conquer, interactive

Vladik and cards

binary search, bitmasks, brute force, dp

Chloe and the sequence

binary search, bitmasks, constructive algorithms, implementation

Anton and School

bitmasks, constructive algorithms, implementation, math

Xor-matic Number of the Graph

bitmasks, graphs, math, number theory, trees

Matvey's Birthday

bitmasks, graphs

Persistent Bookcase

bitmasks, data structures, dfs and similar, implementation

Vasiliy's Multiset

binary search, bitmasks, data structures, trees

LRU

bitmasks, dp, math, probabilities

Travelling Through the Snow Queen's Kingdom

bitmasks, brute force, divide and conquer, graphs

Another Sith Tournament

bitmasks, dp, math, probabilities

Vanya and Label

bitmasks, combinatorics, implementation, strings

Binary Table

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

Gambling Nim

bitmasks, math, matrices, probabilities

Yash And Trees

bitmasks, data structures, dfs and similar, math, number theory

New Year Tree

bitmasks, data structures, trees

New Year and Old Property

bitmasks, brute force, implementation

Sandy and Nuts

bitmasks, dp, trees

Boolean Function

bitmasks, dp, expression parsing

Three Logos

bitmasks, brute force, constructive algorithms, geometry, implementation, math

Kefa and Dishes

bitmasks, dp

Raising Bacteria

bitmasks

Party

bitmasks, brute force, graph matchings

Tree Requests

binary search, bitmasks, constructive algorithms, dfs and similar, graphs, trees

Restoring Map

bitmasks, constructive algorithms, trees

Preparing Olympiad

bitmasks, brute force

Mike and Foam

bitmasks, combinatorics, dp, math, number theory

Remembering Strings

bitmasks, dp

Tavas and SaDDas

bitmasks, brute force, combinatorics, implementation

Simplified Nonogram

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

Fuzzy Search

bitmasks, brute force, fft

Anya and Cubes

binary search, bitmasks, brute force, dp, math, meet-in-the-middle

Second price auction

bitmasks, probabilities

Permutations

bitmasks, divide and conquer, math

Fox And Jumping

bitmasks, brute force, dp, math

Misha and XOR

bitmasks

Bits

bitmasks, constructive algorithms

Game with Strings

bitmasks, dp, probabilities

Dreamoon and WiFi

bitmasks, brute force, combinatorics, dp, math, probabilities

Design Tutorial: Increase the Constraints

bitmasks, data structures, fft

Fedor and New Game

bitmasks, brute force, constructive algorithms, implementation

Little Pony and Harmony Chest

bitmasks, brute force, dp

Devu and Flowers

bitmasks, combinatorics, number theory

Jzzhu and Numbers

bitmasks, combinatorics, dp

Borya and Hanabi

bitmasks, brute force, implementation

Valera and Number

bitmasks, dp, math, probabilities

The Child and Set

bitmasks, greedy, implementation, sortings

Random Task

binary search, bitmasks, combinatorics, dp, math

Guess the Tree

bitmasks, constructive algorithms, dp, greedy, trees

Sereja and Table

bitmasks, greedy

Cunning Gena

bitmasks, dp, greedy, sortings

2048

bitmasks, dp

Roman and Numbers

bitmasks, brute force, combinatorics, dp, number theory

Inna and Binary Logic

binary search, bitmasks, data structures

Fox and Minimal path

bitmasks, constructive algorithms, graphs, implementation, math

Bear and Floodlight

bitmasks, dp, geometry

New Year Letter

bitmasks, brute force, dp

Captains Mode

bitmasks, dp, games