Letter Exchange

constructive algorithms

Monsters (easy version)

brute force, greedy

Weighed Tree Radius

data structures, divide and conquer, implementation, trees

Double Sort II

dfs and similar, flows, graph matchings, graphs

Game of the Year

brute force, data structures, math, number theory

Different Arrays

brute force, dp, implementation

Yet Another Tournament

binary search, greedy, sortings

Matrix of Differences

constructive algorithms, math

Make it Beautiful

constructive algorithms, math, sortings

Window Signals (hard version)

Window Signals (easy version)

Diverse Coloring

constructive algorithms, trees

Bracket Insertion

combinatorics, dp, math, trees

Rectangle Shrinking

binary search, brute force, data structures, greedy, implementation, two pointers

Many Perfect Squares

brute force, math, number theory

Equal Frequencies

brute force, constructive algorithms, greedy, implementation, sortings, strings

Going to the Cinema

brute force, greedy, sortings

Parallel Projection

geometry, math

Delicious Dessert

binary search, dsu, hashing, math, number theory, string suffix structures

Three Chairs

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

Josuke and Complete Graph

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

Bit Guessing Game

binary search, bitmasks, constructive algorithms, interactive

GCD Partition

brute force, greedy, math, number theory

Hayato and School

constructive algorithms, greedy

Olympic Team Building

brute force, meet-in-the-middle

The Game of the Century

constructive algorithms, graphs, shortest paths

Xorcerer's Stones

bitmasks, constructive algorithms, dp, trees

Anya's Simultaneous Exhibition

constructive algorithms, graphs, greedy, interactive, sortings

Boris and His Amazing Haircut

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

Least Prefix Sum

data structures, greedy

MKnez's ConstructiveForces Task

constructive algorithms, math

Hall of Fame

constructive algorithms, greedy, strings

Maximizing Root

dfs and similar, dp, graphs, math, number theory, trees

The Tree Has Fallen!

bitmasks, dfs and similar, math, trees

Flexible String Revisit

combinatorics, dp, math, probabilities

Flexible String

bitmasks, brute force, strings

The Forbidden Permutation

greedy, math

Flip Flop Sum

greedy, implementation

Comfortably Numb

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

Edge Reverse

binary search, dfs and similar, graphs, trees

Score of a Tree

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

Quiz Master

binary search, math, number theory, sortings, two pointers

Emordnilap

combinatorics, greedy, math

Everybody Likes Good Arrays!

greedy, math

Count Permutations

math

Parmigiana With Seafood

binary search, dp, greedy, trees

Controllers

binary search, math

Uniform Chemistry

dp, math

Italian Data Centers

graphs, shortest paths

Spinach Pizza

games, geometry, greedy, interactive

Beppa and SwerChat

two pointers

Another Wine Tasting Event

combinatorics, constructive algorithms, math, strings

Train Splitting

constructive algorithms, graphs, greedy

Crossing the Railways

data structures, dp

Teamwork

constructive algorithms, greedy, math

Library game

games, greedy, interactive, sortings

Vittorio Plays with LEGO Bricks

dp, geometry

Walking Boy

greedy

Laboratory on Pluto

constructive algorithms, dp, greedy, math

The Human Equation

greedy, implementation

Friendly Spiders

dfs and similar, graphs, math, number theory, shortest paths

Interesting Sequence

bitmasks, math

Gardener and the Array

bitmasks, constructive algorithms

Gardener and the Capybaras (hard version)

constructive algorithms, greedy

Gardener and the Capybaras (easy version)

brute force, constructive algorithms, implementation

Maximum Permutation

constructive algorithms

Segment Covering

brute force, combinatorics, constructive algorithms, data structures, dp, trees

Magician and Pigs (Hard Version)

binary search, brute force, data structures, implementation

Magician and Pigs (Easy Version)

brute force, data structures, implementation

Two Chess Pieces

dfs and similar, dp, greedy, trees

Same Count One

brute force, constructive algorithms, greedy, implementation, two pointers

Ice and Fire

constructive algorithms, dp, greedy

Coloring

constructive algorithms, greedy, math

Add Plus Minus Sign

constructive algorithms, math

Lisa's Sequences

dp

King's Puzzle

constructive algorithms

Jumbled Trees

constructive algorithms, math

Interactive Factorial Guessing

brute force, games, implementation, interactive

Hot and Cold

binary search, interactive

Game of Questions

bitmasks, combinatorics, dp, fft, math, probabilities

Football

constructive algorithms

Easy Assembly

greedy, sortings

Dominoes

combinatorics, flows, graph matchings, greedy

Cactus Meets Torus

BinCoin

binary search, divide and conquer, hashing, implementation, probabilities, trees

Amazing Trick

constructive algorithms, graph matchings, math, probabilities

Gaining Rating

binary search, greedy, implementation, math, sortings, two pointers

Copy of a Copy of a Copy

constructive algorithms, dfs and similar, graphs, implementation, sortings

Permutation Game

games

Absolute Sorting

constructive algorithms, math

Different Differences

constructive algorithms, greedy, math

Matrix Rotation

brute force, implementation

A+B?

implementation

Hossam and Range Minimum Query

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

Hossam and a Letter

brute force, dp, implementation, two pointers

Hossam and (sub-)palindromic tree

brute force, data structures, dfs and similar, dp, strings, trees

Hossam and Trainees

greedy, math, number theory

Hossam and Friends

binary search, constructive algorithms, dp, two pointers

Hossam and Combinatorics

combinatorics, math, sortings

Koxia, Mahiru and Winter Festival

constructive algorithms