Present

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

Nearest Beautiful Number (hard version)

bitmasks, brute force, constructive algorithms, dfs and similar, dp, greedy

Binary Median

binary search, bitmasks, brute force, constructive algorithms

Xor-Paths

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

New Year Tree

bitmasks, data structures, trees

Sweets Game

bitmasks, dfs and similar, dp, games, implementation

2048

bitmasks, dp

New Year Letter

bitmasks, brute force, dp

Second price auction

bitmasks, probabilities

Jamie and Binary Sequence (changed after round)

bitmasks, greedy, math

Elongated Matrix

binary search, bitmasks, brute force, dp, graphs

Choosing The Commander

bitmasks, data structures, trees

Rotate Columns (easy version)

bitmasks, brute force, dp, greedy, sortings

Ehab and another another xor problem

bitmasks, constructive algorithms, implementation, interactive

Vasya and Good Sequences

bitmasks, dp

Unusual Sequences

bitmasks, combinatorics, dp, math, number theory

Coprime Subsequences

bitmasks, combinatorics, number theory

Nene and the Mex Operator

bitmasks, brute force, constructive algorithms, divide and conquer, dp, greedy, implementation, math

Looking for Order

bitmasks, dp

Moving Chips

bitmasks, dp, greedy

Small GCD

bitmasks, brute force, dp, math, number theory

GCD Guess

bitmasks, chinese remainder theorem, constructive algorithms, games, interactive, math, number theory

Roman and Numbers

bitmasks, brute force, combinatorics, dp, number theory

Reverse

bitmasks, constructive algorithms, dfs and similar, implementation, math, strings

XOR Inverse

bitmasks, data structures, divide and conquer, dp, greedy, math, sortings, strings, trees

Bitwise Queries (Easy Version)

bitmasks, constructive algorithms, interactive, math

Danil and a Part-time Job

bitmasks, data structures, trees

Little Pony and Harmony Chest

bitmasks, brute force, dp

505

bitmasks, brute force, constructive algorithms, dp, greedy, implementation

Square Subsets

bitmasks, combinatorics, dp, math

XOR-gun

bitmasks, brute force, constructive algorithms

Minimax Problem

binary search, bitmasks, dp

XOR on Segment

bitmasks, data structures

Memory for Arrays

binary search, bitmasks, greedy

Table

bitmasks, combinatorics, dp, math

Permutation Sum

bitmasks, combinatorics, dp, implementation, meet-in-the-middle

Hongcow's Game

bitmasks, divide and conquer, interactive

Open Communication

bitmasks, brute force

Cunning Gena

bitmasks, dp, greedy, sortings

Fox and Minimal path

bitmasks, constructive algorithms, graphs, implementation, math

Paths in a Complete Binary Tree

bitmasks, trees

Bookshelves

bitmasks, dp, greedy

Score of a Tree

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

Mahmoud and Ehab and the xor-MST

bitmasks, dp, graphs, implementation, math

The Wu

bitmasks, brute force, data structures

Shuffling Songs

bitmasks, dfs and similar, dp, graphs, hashing, implementation, strings

Dasha and Nightmares

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

Alex and Julian

bitmasks, math, number theory

Birthday Gift

bitmasks, brute force, constructive algorithms, greedy, implementation

Rudolf and CodeVid-23

bitmasks, dp, graphs, greedy, shortest paths

Median String

bitmasks, math, number theory, strings

Yet Another Problem

binary search, bitmasks, constructive algorithms, data structures

Ehab and the Expected XOR Problem

bitmasks, constructive algorithms

Fish

bitmasks, dp, probabilities

GameGame

bitmasks, constructive algorithms, dp, games, greedy, math

2+ doors

2-sat, bitmasks, graphs, greedy

Tree XOR

bitmasks, dfs and similar, dp, greedy, trees

Fox And Jumping

bitmasks, brute force, dp, math

Need for Pink Slips

bitmasks, brute force, dfs and similar, implementation, math, probabilities

MinOr Tree

bitmasks, dfs and similar, dsu, graphs, greedy

XOR Construction

bitmasks, constructive algorithms, data structures, math, string suffix structures, trees

XOR Guessing

bitmasks, interactive, math

Nearest Beautiful Number (easy version)

binary search, bitmasks, brute force, constructive algorithms, dfs and similar, greedy

Genius's Gambit

bitmasks, constructive algorithms, greedy, math

Strange Definition

bitmasks, graphs, hashing, math, number theory

Shortest Cycle

bitmasks, brute force, graphs, shortest paths

Fill The Bag

bitmasks, greedy

Dr. Evil Underscores

bitmasks, brute force, dfs and similar, divide and conquer, dp, greedy, strings, trees

Kim's Quest

bitmasks, combinatorics, dp

Bitwise Formula

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

Permutations

bitmasks, divide and conquer, math

Bit Guessing Game

binary search, bitmasks, constructive algorithms, interactive

Korney Korneevich and XOR (easy version)

bitmasks, dp, greedy

Lisa and the Martians

bitmasks, greedy, math, strings, trees

Sheikh (Easy version)

binary search, bitmasks, greedy, two pointers

Magic Will Save the World

binary search, bitmasks, brute force, dp

Xor-Subsequence (easy version)

bitmasks, brute force, dp, strings, trees, two pointers

Infinite Set

bitmasks, dp, math, matrices, number theory, strings

Maximum AND

bitmasks, dfs and similar, divide and conquer, greedy, sortings

Take a Guess

bitmasks, constructive algorithms, interactive, math

Maximum Subsequence

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

Array Differentiation

bitmasks, brute force, constructive algorithms, dfs and similar, dp, graphs, math

Zookeeper and The Infinite Zoo

bitmasks, constructive algorithms, dp, greedy, math

Apollo versus Pan

bitmasks, brute force, math

Increasing Subsequences

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

Edge Weight Assignment

bitmasks, constructive algorithms, dfs and similar, greedy, math, trees

Mikasa

binary search, bitmasks, greedy, implementation

Kefa and Dishes

bitmasks, dp

Vasiliy's Multiset

binary search, bitmasks, data structures, trees

Fix the String

*special problem, bitmasks, dp, greedy

Borya and Hanabi

bitmasks, brute force, implementation

k-Interesting Pairs Of Integers

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

Three Logos

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

Tree Diameter

bitmasks, graphs, interactive

Subsequence Counting

bitmasks, constructive algorithms, greedy, implementation

Maximum And Queries (easy version)

binary search, bitmasks, brute force, greedy

Fixed Prefix Permutations

binary search, bitmasks, data structures, hashing, math, sortings

Dreamoon Likes Sequences

bitmasks, combinatorics, math

Candy Party (Easy Version)

bitmasks, constructive algorithms, graphs, greedy, implementation, math

Bitwise Operation Wizard

bitmasks, constructive algorithms, greedy, interactive, math