XOR Partition

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

Vika and Wiki

binary search, bitmasks, combinatorics, divide and conquer, dp, math

The Boss's Identity

binary search, bitmasks, data structures, dfs and similar, greedy, math, sortings

Vampiric Powers, anyone?

bitmasks, brute force, dp, greedy

Hamon Odyssey

bitmasks, greedy, two pointers

Rudolf and CodeVid-23

bitmasks, dp, graphs, greedy, shortest paths

Tree Weights

bitmasks, constructive algorithms, data structures, dfs and similar, implementation, math, matrices, number theory, trees

Sum in Binary Tree

bitmasks, combinatorics, math, trees

Tenzing and Random Real Numbers

bitmasks, dp, graphs, math, probabilities

Tenzing and Books

bitmasks, greedy, math

Binary Cafe

bitmasks, combinatorics, math

Good Graph

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

Twin Clusters

bitmasks, brute force, constructive algorithms, math, probabilities

Don't Blame Me

bitmasks, combinatorics, dp, math

Mr. Perfectly Fine

bitmasks, greedy, implementation

Walk the Runway

bitmasks, brute force, data structures, dp, graphs, implementation, sortings

XOR Counting

bitmasks, combinatorics, dp, math

Subsequence Addition (Hard Version)

bitmasks, dp, greedy, implementation, sortings

We Need the Zero

bitmasks, brute force

Code Lock

bitmasks, dp

Routing

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

The Very Beautiful Blanket

bitmasks, constructive algorithms

Dasha and Nightmares

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

Tree Cutting

bitmasks, dfs and similar, dp

Removal Sequences

bitmasks, dfs and similar, graphs

Fixed Prefix Permutations

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

Vlad and a Pair of Numbers

bitmasks, constructive algorithms

Serval and Brain Power

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

Serval and Shift-Shift-Shift

bitmasks, brute force, constructive algorithms, implementation

XOR, Tree, and Queries

bitmasks, constructive algorithms, dfs and similar, dsu, graphs, greedy, implementation, trees

The Harmonization of XOR

bitmasks, constructive algorithms, greedy, math

Three Chairs

bitmasks, brute force, combinatorics, data structures, dp, number theory, sortings

Bit Guessing Game

binary search, bitmasks, constructive algorithms, interactive

Xorcerer's Stones

bitmasks, constructive algorithms, dp, trees

The Tree Has Fallen!

bitmasks, dfs and similar, math, trees

Flexible String

bitmasks, brute force, strings

Comfortably Numb

bitmasks, data structures, divide and conquer, strings, trees

Score of a Tree

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

Interesting Sequence

bitmasks, math

Gardener and the Array

bitmasks, constructive algorithms

Game of Questions

bitmasks, combinatorics, dp, fft, math, probabilities

Hossam and Range Minimum Query

binary search, bitmasks, data structures, hashing, probabilities, strings, trees

Koxia and Sequence

bitmasks, combinatorics, dp, math, number theory

Algebra Flash

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

Access Levels

bitmasks, dsu, flows, graph matchings

Absolute Maximization

bitmasks, constructive algorithms, greedy, math

SlavicG's Favorite Problem

bitmasks, dfs and similar, graphs

Circular Xor Reversal

bitmasks, constructive algorithms

ConstructOR

bitmasks, chinese remainder theorem, combinatorics, constructive algorithms, math, number theory

Yet Another Problem

binary search, bitmasks, constructive algorithms, data structures

Antifibonacci Cut

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

Orray

bitmasks, brute force, greedy, math, sortings

Kirill and Company

bitmasks, brute force, dfs and similar, dp, flows, graphs, shortest paths

Keyboard Design

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

Cleaning Robot

bitmasks, dp

Zeros and Ones

bitmasks, divide and conquer, dp, math

Sheikh (Hard Version)

binary search, bitmasks, brute force, greedy, implementation, two pointers

Sheikh (Easy version)

binary search, bitmasks, greedy, two pointers

Even Subarrays

bitmasks, brute force, hashing, math, number theory

Almost Sorted

bitmasks, data structures, dp

Illumination

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

Mainak and Interesting Sequence

bitmasks, constructive algorithms, math

Field Photography

bitmasks, data structures, sortings

Deducing Sortability

binary search, bitmasks, math

Even-Odd XOR

bitmasks, constructive algorithms, greedy

Maximum AND

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

Xor-Subsequence (hard version)

bitmasks, data structures, dp, strings, trees

Xor-Subsequence (easy version)

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

Swap and Maximum Block

bitmasks, data structures, dfs and similar, divide and conquer, dp

2+ doors

2-sat, bitmasks, graphs, greedy

Lost Array

bitmasks, combinatorics, constructive algorithms, dp, math

XOR Triangle

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

Multiset of Strings

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

XOR Tree

bitmasks, data structures, dfs and similar, dsu, greedy, trees

Bugaboo

bitmasks, constructive algorithms, dp, number theory

Mark and the Online Exam

bitmasks, constructive algorithms, interactive, probabilities

Mark and Professor Koro

binary search, bitmasks, brute force, combinatorics, data structures, greedy

Good Key, Bad Key

bitmasks, brute force, dp, greedy, math

Almost Ternary Matrix

bitmasks, constructive algorithms, matrices

Long Binary String

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

XOR Mixup

bitmasks, brute force

NIT orz!

bitmasks, greedy

ANDfinity

bitmasks, brute force, constructive algorithms, dfs and similar, dsu, graphs

Patchouli's Magical Talisman

bitmasks, constructive algorithms, greedy, sortings

Cirno's Perfect Bitmasks Classroom

bitmasks, brute force

AND Sorting

bitmasks, constructive algorithms, sortings

Moving Chips

bitmasks, dp, greedy

Formalism for Formalism

bitmasks, dp, math

Typical Party in Dorm

bitmasks, combinatorics, dp, strings

Anti-Theft Road Planning

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

Power or XOR?

bitmasks, combinatorics, math, number theory

Jee, You See?

bitmasks, combinatorics, dp

Hemose on the Tree

bitmasks, constructive algorithms, dfs and similar, trees

Maximal AND

bitmasks, greedy, math

MinimizOR

bitmasks, brute force, data structures, divide and conquer, greedy, implementation, two pointers

GCD Guess

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

Getting Zero

bitmasks, brute force, dfs and similar, dp, graphs, greedy, shortest paths

AND-MEX Walk

bitmasks, brute force, constructive algorithms, dfs and similar, dsu, graphs

Bit Flipping

bitmasks, constructive algorithms, greedy, strings

388535 (Hard Version)

bitmasks, brute force, data structures, math