Ultra-Meow

combinatorics, dp, math

Distance to Different

combinatorics, dp, math

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

Reconstruction

brute force, dp, math

Shuffle

dp, greedy, trees

''a'' String Problem

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

array-value

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

I Love Balls

combinatorics, math, probabilities

Number of k-good subarrays

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

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

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

XORificator

bitmasks, brute force, greedy, hashing

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

Chain Queries

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

Money Buys Less Happiness Now

data structures, greedy, sortings

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 (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

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

Fenwick Tree

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

Reverse Card (Hard Version)

brute force, math, number theory

Folding Strip

constructive algorithms, greedy, strings

Observation Towers

*special problem

Narrow Paths

*special problem, combinatorics

Carousel of Combinations

brute force, combinatorics, dp, math, number theory

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

Chain Reaction

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

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

Scooter

graphs, greedy

Dating

greedy, sortings, trees

Rare Coins

combinatorics, math, probabilities

Clique Partition

brute force, constructive algorithms, graphs, greedy, implementation

Nobody is needed

2-sat, data structures, dfs and similar, dp

Girl Permutation

combinatorics, dp, math, number theory

Cook and Porridge

binary search, constructive algorithms, data structures, implementation

Counting Is Fun (Easy Version)

brute force, combinatorics, dp, math

Tree Compass

constructive algorithms, dfs and similar, greedy, trees

Non-Palindromic Substring

hashing, implementation, math, strings

Farm Game

combinatorics, games

Learning to Paint

binary search, data structures, dfs and similar, dp, greedy, implementation, sortings

Rudolf and Subway

constructive algorithms, dfs and similar, graphs, shortest paths

Tree Quiz

There and Back Again

Personality Test

Forming Groups

Duplicates

Pokémon Arena

data structures, graphs, greedy, implementation, shortest paths, sortings

Pinball

binary search, data structures, implementation, math, two pointers

Distance Learning Courses in MAC

bitmasks, brute force, data structures, greedy, math

XOR Break --- Game Version

bitmasks, games, greedy, interactive

XOR Break --- Solo Version

bitmasks, constructive algorithms, greedy

Turtle Magic: Royal Turtle Shell Pattern

bitmasks, brute force, combinatorics, constructive algorithms, dfs and similar, math

Turtle Mission: Robot and the Earthquake

dfs and similar, dp, graphs, shortest paths

Moving Platforms

graphs, math, number theory, shortest paths

One-Dimensional Puzzle

combinatorics, math, number theory

2..3...4.... Wonderful! Wonderful!

combinatorics, dp, math

Sum over all Substrings (Hard Version)

bitmasks, divide and conquer, dp, dsu, greedy, implementation, strings

Sasha and the Wedding Binary Search Tree

brute force, combinatorics, data structures, dfs and similar, math, trees

Sasha and the Happy Tree Cutting

bitmasks, brute force, dfs and similar, dp, graphs, greedy, math, trees

Modular Sequence

brute force, constructive algorithms, dp, graphs, greedy, math, number theory

Paint Charges

data structures, dp, greedy, math

Vlad and Avoiding X

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

Fractal Origami

geometry, math, matrices

Space Harbour

data structures, implementation, math, sortings

Count Paths

data structures, dfs and similar, dp, dsu, graphs, trees

Replace on Segment

dp, graph matchings

Mischievous Shooter

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

Smooth Sailing (Easy Version)

binary search, brute force, data structures, dfs and similar, dsu, graphs, shortest paths

Counting Binary Strings

combinatorics, dp, math

Tree Diameter

interactive, trees

Wine Factory (Easy Version)

data structures, greedy

01 Tree

constructive algorithms, data structures, dsu, greedy, sortings, trees

Caterpillar on a Tree

dfs and similar, graphs, greedy, implementation, sortings, trees

ace5 and Task Order

constructive algorithms, divide and conquer, implementation, interactive, probabilities, sortings