Parallel Swaps Sort

constructive algorithms, data structures

Redundant Routes

constructive algorithms, dp, trees

Three Minimums

combinatorics, constructive algorithms, divide and conquer, dp, fft, math

Min-Sum-Max

constructive algorithms, dp, greedy

BinaryStringForces

constructive algorithms, data structures, dp

Long Recovery

constructive algorithms, dfs and similar

Four Stones

constructive algorithms

Slime and Hats

constructive algorithms, dp, greedy

Neighbour Ordering

constructive algorithms, graphs

Mio and Lucky Array

constructive algorithms, fft, math, strings

Koxia, Mahiru and Winter Festival

constructive algorithms

Impressionism

constructive algorithms, graphs, implementation, math

Permutation Weight (Hard Version)

constructive algorithms, greedy

Copium Permutation

constructive algorithms, data structures, greedy

Anti-Proxy Attendance

constructive algorithms, dp, interactive, ternary search

Maximum Permutation

constructive algorithms

Balance the Cards

constructive algorithms, data structures, divide and conquer, geometry, graphs, implementation

Lost Nodes

constructive algorithms, dp, graphs, interactive, sortings, trees

Bugaboo

bitmasks, constructive algorithms, dp, number theory

Omkar and Mosaic

combinatorics, constructive algorithms, math

Tree LGM

constructive algorithms, divide and conquer, games, trees

Euler tour

constructive algorithms, trees

OH NO1 (-2-3-4)

constructive algorithms, graphs, math

Become Big For Me

combinatorics, constructive algorithms, greedy, math, number theory

Xor on Figures

constructive algorithms, fft, math

Rin and The Unknown Flower

constructive algorithms, greedy, interactive, math

Cactus Revenge

constructive algorithms

Beautiful Fibonacci Problem

constructive algorithms, number theory

Intergalactic Sliding Puzzle

combinatorics, constructive algorithms, math

Railway Construction

brute force, constructive algorithms, data structures, graphs, shortest paths

Negative Time Summation

constructive algorithms

Minimum Segments

constructive algorithms

Beauty of a Permutation

constructive algorithms, math

Rivalries

constructive algorithms, data structures, greedy

Hard Cut

constructive algorithms, dfs and similar, divide and conquer, math

Bus Routes

binary search, constructive algorithms, dfs and similar, greedy, trees

Recover the Tree

constructive algorithms, trees

Egor and an RPG game

constructive algorithms, greedy

Cactus Transformation

constructive algorithms

Dirty plates

constructive algorithms, math

Ela and Prime GCD

constructive algorithms, math, number theory

Interactive Mex Tree

constructive algorithms, dfs and similar, interactive, trees

What a Reversal

constructive algorithms

Maximum Adjacent Pairs

constructive algorithms, graph matchings

Sophisticated Device

constructive algorithms

Ball-Stackable

constructive algorithms, data structures, dp, trees

New Road Network

constructive algorithms, greedy, math

Squares

constructive algorithms, data structures, dp, graphs, trees

Balanced Reversals

constructive algorithms

Gold Experience

constructive algorithms, graphs, math, number theory, probabilities

Set Merging

constructive algorithms, divide and conquer

Starry Night Camping

constructive algorithms, flows, graphs

Growing Trees

binary search, constructive algorithms, flows, graphs, greedy

Public Service

constructive algorithms, graphs, trees

Help BerLine

constructive algorithms

Ancient civilizations

constructive algorithms, geometry

Xor-quiz

constructive algorithms, dp, interactive, math, number theory

Planar Perimeter

constructive algorithms, graphs

Game of AI (easy version)

combinatorics, constructive algorithms, dp, fft, math

A Preponderant Reunion

constructive algorithms, dp

Diverse Coloring

constructive algorithms, trees

Cycle Palindrome

constructive algorithms, graphs, math

Listening to Music

constructive algorithms, data structures

Pepe Racing

constructive algorithms, implementation, interactive, sortings

Cross Xor

constructive algorithms, graphs, math, matrices

Distance Matching

constructive algorithms, dfs and similar, trees

Segment Covering

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

Yui and Mahjong Set

constructive algorithms, interactive

New Year and Forgotten Tree

constructive algorithms, flows, graphs

Restoring Map

bitmasks, constructive algorithms, trees

Company Acquisitions

constructive algorithms, math

Homework

constructive algorithms

Unequal Adjacent Elements

constructive algorithms, sortings

Princess and Her Shadow

constructive algorithms, shortest paths

Connected Cubes

constructive algorithms, games

Dangerous Laser Power

constructive algorithms, dsu, sortings

Deja Vu

constructive algorithms, dp

Harry The Potter

brute force, constructive algorithms, dp, fft, implementation, math

Create a Maze

constructive algorithms

Magic Square

combinatorics, constructive algorithms, implementation

Perpetual Motion Machine

constructive algorithms, dp, graphs, implementation, math, trees

Two Permutations (Hard Version)

constructive algorithms

Tree Calendar

brute force, constructive algorithms, data structures, dfs and similar, sortings, trees

Four Vertices

constructive algorithms, data structures, graphs, greedy, implementation, shortest paths

Good Colorings

binary search, constructive algorithms, graphs, interactive

Xor Permutations

constructive algorithms, math

Dreamoon Likes Strings

constructive algorithms, data structures

The same permutation

constructive algorithms

Get Ready for the Battle

constructive algorithms, implementation

Berserk Robot

constructive algorithms, math, sortings

To Make 1

bitmasks, constructive algorithms, dp, greedy, number theory

Tree-Tac-Toe

constructive algorithms, games, trees

Algoland and Berland

constructive algorithms, divide and conquer, geometry

Flow Optimality

constructive algorithms, flows, math

Alpha planetary system

constructive algorithms, graphs, shortest paths

Decent Division

constructive algorithms, data structures

Weird LCM Operations

brute force, constructive algorithms, number theory

Antifibonacci Cut

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

Flower-like Pseudotree

constructive algorithms, graphs, greedy, implementation, trees

Median Queries

constructive algorithms, interactive, probabilities