Running in Pairs

constructive algorithms, greedy, math

Chips

constructive algorithms, implementation

Minimizing Difference

binary search, constructive algorithms, greedy, sortings, ternary search, two pointers

Paint the Tree

brute force, constructive algorithms, dp, graphs, implementation, trees

Planar Perimeter

constructive algorithms, graphs

Tile Painting

constructive algorithms, math, number theory

Balanced Reversals

constructive algorithms

Balanced Removals (Harder)

binary search, constructive algorithms, divide and conquer, greedy, implementation, sortings

Balanced Removals (Easier)

constructive algorithms, geometry, greedy

Labs

constructive algorithms, greedy, implementation

Middle-Out

constructive algorithms, greedy, strings

One Node is Gone

constructive algorithms, implementation, trees

Complete Tripartite

brute force, constructive algorithms, graphs, hashing, implementation

Not Same

constructive algorithms

Messy

constructive algorithms

Box

constructive algorithms

To Make 1

bitmasks, constructive algorithms, dp, greedy, number theory

Tree Factory

constructive algorithms, greedy, trees

Knights

constructive algorithms, greedy

Alpha planetary system

constructive algorithms, graphs, shortest paths

Coloring Edges

constructive algorithms, dfs and similar, graphs

Swap Letters

constructive algorithms, greedy

Tiles Placement

constructive algorithms, dfs and similar, trees

Petya and Construction Set

constructive algorithms, graphs, math, sortings, trees

Two Small Strings

brute force, constructive algorithms

Paint the Digits

constructive algorithms, greedy, implementation

Magic Grid

constructive algorithms

Square Filling

constructive algorithms, greedy, implementation

Beauty of a Permutation

constructive algorithms, math

Almost All

constructive algorithms, trees

Almost Equal

constructive algorithms, greedy, math

Print a 1337-string...

combinatorics, constructive algorithms, math, strings

Matching vs Independent Set

constructive algorithms, graphs, greedy, sortings

K-th Path

brute force, constructive algorithms, shortest paths, sortings

Connected Component on a Chessboard

constructive algorithms, implementation

Odd Sum Segments

constructive algorithms, math

Three Piles of Candies

brute force, constructive algorithms, math

Scissors and Tape

*special problem, constructive algorithms, geometry

Add on a Tree: Revolution

constructive algorithms, dfs and similar, implementation, trees

Vasya And Array

constructive algorithms, greedy, implementation

Vus the Cossack and Numbers

constructive algorithms, greedy, math

Complete Mirror

constructive algorithms, dfs and similar, dp, hashing, implementation, trees

Tolik and His Uncle

constructive algorithms

Archaeology

brute force, constructive algorithms, greedy, strings

Prime Graph

constructive algorithms, greedy, math, number theory

Ehab and the Big Finale

constructive algorithms, divide and conquer, graphs, implementation, interactive, trees

Ehab and the Expected XOR Problem

bitmasks, constructive algorithms

Ehab and a Special Coloring Problem

constructive algorithms, number theory

Ehab Fails to Be Thanos

constructive algorithms, greedy, sortings

Nauuo and Chess

constructive algorithms, greedy

Nauuo and Portals

constructive algorithms

Longest Saw

*special problem, constructive algorithms

Xor Permutations

constructive algorithms, math

Bicolored RBS

constructive algorithms, greedy

The LCMs Must be Large

bitmasks, brute force, constructive algorithms, math, number theory

All the Vowels Please

constructive algorithms, math, number theory

Magical Permutation

bitmasks, brute force, constructive algorithms, data structures, graphs, math

Winding polygonal line

constructive algorithms, geometry, greedy, math

Permutation recovery

constructive algorithms, data structures, dfs and similar, graphs, greedy, math, sortings

The minimal unique substring

constructive algorithms, math, strings

The Party and Sweets

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

Inverse of Rows and Columns

brute force, constructive algorithms

Maximum Balanced Circle

constructive algorithms, dp, greedy, two pointers

N Problems During K Days

constructive algorithms, greedy, math

Serval and Toy Bricks

constructive algorithms, greedy

Neko and Flashback

constructive algorithms, dfs and similar, graphs

Neko Performs Cat Furrier Transform

bitmasks, constructive algorithms, dfs and similar, math

Problem for Nazar

constructive algorithms, math

Dima and a Bad XOR

bitmasks, brute force, constructive algorithms, dp

Prefix Sum Primes

constructive algorithms, greedy, math, number theory

Gold Experience

constructive algorithms, graphs, math, number theory, probabilities

Foo Fighters

bitmasks, constructive algorithms

Earth Wind and Fire

constructive algorithms, greedy, math, sortings, two pointers

Crazy Diamond

constructive algorithms, sortings

Equalize Them All

constructive algorithms, greedy

Two Shuffled Sequences

constructive algorithms, sortings

Privatization of Roads in Treeland

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

Cooperative Game

constructive algorithms, interactive, number theory

Nastya Is Transposing Matrices

constructive algorithms, sortings

Nastya Is Playing Computer Games

constructive algorithms, math

Spanning Tree with One Fixed Degree

constructive algorithms, dfs and similar, dsu, graphs, greedy

Asya And Kittens

constructive algorithms, dsu

Wrong Answer

constructive algorithms

Once in a casino

constructive algorithms, greedy, implementation, math

Get Ready for the Battle

constructive algorithms, implementation

Ramesses and Corner Inversion

constructive algorithms, greedy, implementation, math

Yet Another Ball Problem

constructive algorithms, implementation

Palindromic Matrix

constructive algorithms, implementation

Decypher the String

bitmasks, chinese remainder theorem, constructive algorithms, interactive, math

Yet Another Array Partitioning Task

constructive algorithms, greedy, sortings

Tree-Tac-Toe

constructive algorithms, games, trees

Magic Stones

constructive algorithms, math, sortings

Meaningless Operations

constructive algorithms, math, number theory

Sasha and One More Name

constructive algorithms, hashing, strings

Diverse Garland

constructive algorithms, dp, greedy

Vasya and Maximum Profit

binary search, constructive algorithms, data structures, dp, dsu

Splitting into digits

constructive algorithms, implementation, math

Johnny Solving

constructive algorithms, dfs and similar, graphs, math

Game with modulo

binary search, constructive algorithms, interactive

Grid game

constructive algorithms, implementation