Clean Substrings

combinatorics, data structures, math

MEX Replacement

binary search, brute force, greedy, implementation, math, sortings

Dr. Agos's Dark Mode

brute force, chinese remainder theorem, constructive algorithms, math, strings

Culling Game

binary search, data structures, implementation, two pointers

Cyclic Balance

binary search, constructive algorithms, dp, math

Index Removal

binary search, data structures, math

Busy Beaver

brute force, data structures, divide and conquer, dp, greedy, implementation, sortings

Even If the World Turns

communication, constructive algorithms, expression parsing, greedy, interactive, math, number theory

Whiplash

bitmasks, constructive algorithms, math, sortings

Generational Triplets

bitmasks, combinatorics, dp, math

Double-Rift Dial

data structures, dfs and similar, dsu, implementation, two pointers

Excuse for Breaks

binary search, brute force, greedy, math, two pointers

XOR Sorting (Hard Version)

bitmasks, data structures, greedy

diss_quack and Array Game

bitmasks, brute force, games, greedy

Construct an Array (Hard Version)

2-sat, constructive algorithms, dfs and similar, graphs, implementation

Yura and Deadlines

data structures, dp

Cake Trial

dp, greedy

Permutation Commutation

data structures, graphs, greedy

Vessels, Heights and Two Versions (Hard Version)

data structures, dfs and similar, dsu, greedy, implementation, two pointers

Vlad, Misha and Two Arrays

brute force, combinatorics, dfs and similar, divide and conquer, math

Goods on the Shelf

brute force, data structures, implementation, two pointers

Magical Tiered Cake

constructive algorithms, constructive algorithms, dfs and similar, dp, greedy

Maximum Prefix Sums

constructive algorithms, greedy, implementation, two pointers

Deconstruction Tree

combinatorics, data structures, dp, graphs, trees

Sanae, Cross and Color

binary search, data structures, implementation

Fallen Leaves

dfs and similar, dp, dp, trees, trees

Drowning

binary search, data structures, math

Reserved Reversals

constructive algorithms, dp, greedy, math

Seek the Truth

binary search, bitmasks, constructive algorithms, interactive

Unique Values (Hard version)

binary search, bitmasks, constructive algorithms, interactive

Unique Values (Easy version)

binary search, constructive algorithms, divide and conquer, interactive, math

Definitely Larger

binary search, constructive algorithms, data structures, graphs, greedy, sortings

Flip the Bit (Hard Version)

greedy, implementation, math

RReeppeettiittiioonn

binary search, brute force, implementation, math, number theory

AND-array

bitmasks, combinatorics, math

A Simple RBS Problem

constructive algorithms, math, strings, trees

A Simple GCD Problem (Hard Version)

dp, greedy, number theory

Simons and Dividing the Rhythm

combinatorics, data structures, dp, dsu, math, string suffix structures, strings, strings, strings

Rigged Bracket Sequence

combinatorics, dp, greedy

Mooclear Reactor 2

brute force, data structures, greedy, implementation, sortings

Self-Produced Sequences

*special problem, combinatorics, math

Supersequence

*special problem, binary search, greedy

Interactive Graph (Hard Version)

combinatorics, dfs and similar, dp, graphs, interactive

Parabola Independence

dp, graphs, greedy, math, sortings

The Turtle Strikes Back

dp, graphs, greedy, implementation

Paths in a Tree

dfs and similar, interactive, sortings, trees

Swap to Rearrange

constructive algorithms, dfs and similar, graph matchings, graphs, graphs, graphs, greedy, strings

Sub-RBS (Hard Version)

dp, games, implementation, strings

Little String (Easy Version)

combinatorics, dp, greedy, math, number theory

Nastiness of Segments

binary search, data structures

Cherry Tree

dfs and similar, dp, graphs, trees

LCM is Legendary Counting Master

dp, math, number theory

Tree Coloring (Hard Version)

combinatorics, constructive algorithms, data structures, dfs and similar, greedy, implementation, trees

Doorway

binary search, data structures, sortings

Insolvable Disks

data structures, dp, greedy, math

XOR-factorization

bitmasks, constructive algorithms, dp, greedy, number theory

Blackslex and Another RGB Walking

communication, constructive algorithms, graphs, interactive, number theory, trees

Flatten or Concatenate

binary search, divide and conquer, interactive

Wishing Cards

dp

Taiga's Carry Chains

bitmasks, brute force, dp, greedy, math

Kindergarten Homework

implementation, strings

Birthday

geometry

Sakura Adachi and Optimal Sequences

bitmasks, combinatorics, greedy, math

Anisphia Wynn Palettia and Good Permutations

constructive algorithms, greedy, number theory

Binary Strings and Blocks

combinatorics, data structures, dp

Removal of a Sequence (Hard Version)

binary search, divide and conquer, greedy, implementation, math, number theory

Binary Wine

bitmasks, greedy, math

Marble Council

dp, math, sortings

Diadrash (Easy Version)

binary search, brute force, divide and conquer, implementation, interactive

Beautiful Intervals

constructive algorithms, greedy

Locked Out

binary search, data structures, dp, greedy

Rectangles

brute force, data structures, dp, dsu, greedy, implementation, two pointers

Palindrome Flipping

brute force, constructive algorithms, graphs, implementation, shortest paths, strings

Adjusting Drones

binary search, brute force, data structures, dp, dsu, greedy, implementation, sortings

Find the Last Number

binary search, bitmasks, constructive algorithms, interactive

Catshock

constructive algorithms, dfs and similar, graphs, trees, two pointers

No Cost Too Great (Hard Version)

greedy, math, number theory

Monotone Subsequence

constructive algorithms, graphs, greedy, interactive, math

Limited Edition Shop

data structures, dp

Buratsuta 3

binary search, brute force, data structures, divide and conquer, probabilities

Nezuko in the Clearing

binary search, math, ternary search

Farmer John's Last Wish

binary search, data structures, math, number theory

Max Sum OR (Hard Version)

bitmasks, constructive algorithms, divide and conquer, greedy

Predicting Popularity

binary search, data structures, greedy, sortings

Perfect Cut

*special problem, dp, greedy

A Cruel Segment's Thesis

data structures, greedy, sortings

Maple and Tree Beauty (Hard Version)

bitmasks, brute force, dfs and similar, dp, fft, trees

Antiamuny Wants to Learn Swap

data structures, greedy, two pointers

Prefix Maximum Invariance

binary search, combinatorics, data structures, sortings

From the Unknown (Easy Version)

constructive algorithms, interactive, math

By the Assignment

binary search, bitmasks, combinatorics, dfs and similar, dsu, graphs, math

Chicken Jockey

dp, greedy

Rada and the Chamomile Valley

dfs and similar, graphs, shortest paths

Wafu!

bitmasks, brute force, data structures, dfs and similar, dp, math

Unjust Binary Life

binary search, data structures, greedy, greedy, math, sortings, two pointers

Interactive RBS (Medium Version)

binary search, bitmasks, constructive algorithms, interactive

Interactive RBS (Easy Version)

binary search, bitmasks, constructive algorithms, interactive

Submedians (Easy Version)

binary search, data structures, dp, greedy, math

Ancient Tree

constructive algorithms, data structures, dfs and similar, dsu, greedy, trees

1-1-1, Free Tree!

brute force, data structures, dfs and similar, graphs, implementation, trees