Ultra-Meow

combinatorics, dp, math

Simultaneous Coloring

dfs and similar, divide and conquer, graphs

Distance to Different

combinatorics, dp, math

Heartbeat

combinatorics, dp, fft, math

Range Minimum Sum

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

The Omnipotent Monster Killer

brute force, dfs and similar, dp, trees

Fumo Temple

interactive

Spinning Round (Hard Version)

divide and conquer, dp, trees

Spinning Round (Easy Version)

divide and conquer, dp, trees

Interesting Problem (Hard Version)

dp

Interesting Problem (Easy Version)

dp

Wonderful Tree!

brute force, data structures, dfs and similar, dsu, greedy, trees

Permutation Problem (Hard Version)

brute force, data structures, hashing, math, number theory

Permutation Problem (Simple Version)

binary search, brute force, combinatorics, data structures, math, number theory

Maximize the Largest Component (Hard Version)

data structures, dfs and similar, dp, dsu, implementation

Tower Capturing

combinatorics, dp, geometry

Magic Trick II

constructive algorithms, implementation, sortings

Reconstruction

brute force, dp, math

Shuffle

dp, greedy, trees

''a'' String Problem

brute force, hashing, implementation, math, string suffix structures, strings

Your Loss

bitmasks, brute force, dp, trees

array-value

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

I Love Balls

combinatorics, math, probabilities

Sorting Problem Again

binary search, data structures, sortings

Number of k-good subarrays

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

Turtle and Paths on a Tree

data structures, dp, trees

Turtle and Intersected Segments

data structures, dsu, graphs, greedy

Turtle and Multiplication

constructive algorithms, dfs and similar, graphs, number theory

Yasya and the Mysterious Tree

bitmasks, data structures, dfs and similar, graphs, greedy, strings, trees

Field Division (hard version)

math, sortings

Kostyanych's Theorem

brute force, constructive algorithms, graphs, interactive

Manhattan Triangle

binary search, constructive algorithms, data structures, geometry, implementation, two pointers

Large Graph

data structures, dfs and similar, dsu, graphs, number theory, two pointers

Computing Machine

brute force, data structures, dp, greedy, implementation

Tensor

constructive algorithms, graphs, interactive

XORificator

bitmasks, brute force, greedy, hashing

Remove Bridges

data structures, dfs and similar, dp, greedy, sortings, trees

Splittable Permutations

combinatorics, data structures, dfs and similar, greedy, math, trees

Invertible Bracket Sequences

binary search, combinatorics, data structures, divide and conquer, implementation, two pointers

Mind Bloom

dp

378QAQ and Core

greedy, strings

Zimpha Fan Club

fft, greedy, math, strings

Set

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

Chain Queries

binary search, data structures, dfs and similar, implementation, trees

Money Buys Less Happiness Now

data structures, greedy, sortings

Maximum GCD Sum Queries

bitmasks, brute force, dp, implementation, number theory

Cat, Fox and Swaps

graphs, math, sortings

Cat, Fox and Maximum Array Split

brute force, interactive, math

±1

2-sat, dfs and similar, graphs

Min-Fund Prison (Hard)

bitmasks, dfs and similar, dp, graphs, trees

Min-Fund Prison (Medium)

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

Playing Quidditch (Hard)

implementation

Playing Quidditch (Medium)

implementation

Playing Quidditch (Easy)

implementation

Trails (Hard)

dp, matrices

Trails (Medium)

dp, matrices

Arithmancy (Hard)

interactive

Arithmancy (Medium)

constructive algorithms, interactive, probabilities, strings

Arithmancy (Easy)

brute force, constructive algorithms, interactive, strings

Exact Neighbours (Hard)

constructive algorithms

Exact Neighbours (Medium)

constructive algorithms

Balanced Unshuffle (Hard)

constructive algorithms, trees

Balanced Unshuffle (Medium)

brute force, constructive algorithms, trees

Card Pairing

dp, greedy, hashing, implementation

Unique Array

binary search, data structures, divide and conquer, dp, greedy

Division + LCP (hard version)

binary search, brute force, data structures, dp, hashing, math, string suffix structures, strings

Next and Prev

brute force, data structures, implementation

Again Counting Arrays (Hard Version)

combinatorics, dp, math

Again Counting Arrays (Easy Version)

combinatorics, dp, fft, math

Long Way to be Non-decreasing

binary search, dfs and similar, graphs, implementation, shortest paths, two pointers

Fenwick Tree

bitmasks, brute force, combinatorics, data structures, dp, math, trees

Reverse Card (Hard Version)

brute force, math, number theory

Conference

data structures, flows

Connected Cubes

constructive algorithms, games

Missing Subarray Sum

constructive algorithms

Folding Strip

constructive algorithms, greedy, strings

Necromancer

*special problem

Equal Trees

*special problem, graphs, meet-in-the-middle

Composite Spells

*special problem, dp

Observation Towers

*special problem

Narrow Paths

*special problem, combinatorics

Frequency Mismatch (Hard Version)

binary search, data structures, dfs and similar, hashing, probabilities, trees

Frequency Mismatch (Easy Version)

binary search, data structures, divide and conquer, hashing, probabilities, trees

Carousel of Combinations

brute force, combinatorics, dp, math, number theory

Nene and the Passing Game

constructive algorithms, data structures, dsu, graphs, sortings

Nene vs. Monsters (Hard Version)

brute force, greedy, implementation, math

Nene vs. Monsters (Easy Version)

brute force, implementation, math

Nene and the Mex Operator

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

The Most Reckless Defense

bitmasks, brute force, constructive algorithms, dp, flows, graph matchings, shortest paths

Unique Strings

combinatorics, dp, math

Chain Reaction

binary search, data structures, dsu, greedy, implementation, math, number theory

Growing Trees

binary search, constructive algorithms, flows, graphs, greedy

Thanos Snap

binary search, dp, games, greedy, trees

Clacking Balls

combinatorics, math, probabilities

Inversion Composition

constructive algorithms, data structures, greedy

No Palindromes

brute force, constructive algorithms, divide and conquer, greedy, hashing, implementation, math, strings

Buying Jewels

constructive algorithms, greedy, math

Make Triangle

constructive algorithms, math

Amanda the Amoeba

graphs, implementation, trees, two pointers

Division Avoidance

greedy, math