Knapsack

constructive algorithms, greedy, sortings

Make it Alternating

combinatorics, dp, greedy

Good Numbers (easy version)

brute force, greedy, implementation

Obtain Two Zeroes

binary search, math

Parity Shuffle Sorting

constructive algorithms, sortings

And It's Non-Zero

bitmasks, greedy, math

Permutation Partitions

combinatorics, greedy, math

Good Array

Rudolf and Snowflakes (simple version)

brute force, implementation, math

MEX Game 1

games, greedy

Saving the City

dp, greedy, math, sortings

Perform the Combo

brute force

Two Tables

brute force

Directional Increase

greedy

Simple Game

constructive algorithms, games, greedy, implementation, math

Jeff and Periods

implementation, sortings

Longest Strike

data structures, greedy, implementation, sortings, two pointers

Chat Ban

binary search, math

Divisible Pairs

combinatorics, math, number theory

Mahmoud and Ehab and the bipartiteness

dfs and similar, graphs, trees

Co-growing Sequence

bitmasks, constructive algorithms, greedy

Ice Cream Balls

binary search, combinatorics, constructive algorithms, math

Box Fitting

binary search, bitmasks, data structures, greedy

Di-visible Confusion

constructive algorithms, math, number theory

Forever Winter

dfs and similar, graphs, math

Books Exchange (hard version)

dfs and similar, dsu, math

Not Sitting

games, greedy, sortings

Negative Prefixes

greedy, sortings

Bear and Poker

implementation, math, number theory

Road Construction

constructive algorithms, graphs

Blue-Red Permutation

greedy, math, sortings

Social Network (hard version)

data structures, implementation

Maximal AND

bitmasks, greedy, math

Matching Numbers

constructive algorithms, greedy, math

Slay the Dragon

binary search, greedy, sortings, ternary search

Big Vova

brute force, greedy, math, number theory

Points on Line

binary search, combinatorics, two pointers

Closest Cities

greedy, implementation, math

OR in Matrix

greedy, hashing, implementation

Getting Zero

bitmasks, brute force, dfs and similar, dp, graphs, greedy, shortest paths

Pokémon Army (easy version)

constructive algorithms, dp, greedy

We Were Both Children

brute force, implementation, math, number theory

Canine poetry

dp, greedy, strings

Chocolate

combinatorics

Make a Power of Two

greedy, math, strings

Strong Vertices

math, sortings, trees

Pluses and Minuses

math

3SUM Closure

brute force, data structures

Inhabitant of the Deep Sea

greedy, implementation, math

Two Round Dances

combinatorics, math

Yet Another Problem About Pairs Satisfying an Inequality

binary search, data structures, dp, greedy, sortings

Array and Operations

dp, greedy, math

Equalize

dp, greedy, strings

Find the Different Ones!

binary search, brute force, data structures, dp, dsu, greedy, two pointers

Most socially-distanced subsequence

greedy, two pointers

Romantic Glasses

data structures, greedy, math

Get an Even String

dp, greedy, strings

Nastya and Door

greedy, implementation

A and B and Team Training

greedy, implementation, math, number theory

Inflation

binary search, brute force, greedy, math

Shuffle

math, two pointers

Common Divisors

implementation, math

Number into Sequence

constructive algorithms, math, number theory

Prefix Flip (Easy Version)

constructive algorithms, data structures, strings

A Cookie for You

greedy, implementation, math

Nastia and a Good Array

constructive algorithms, math, number theory

Coin Rows

brute force, constructive algorithms, dp, implementation

Just Eat It!

dp, greedy, implementation

Strange Birthday Party

binary search, dp, greedy, sortings, two pointers

3SUM

brute force, math

Rumor

dfs and similar, graphs, greedy

Anton and currency you all know

greedy, math, strings

Social Distance

constructive algorithms, greedy, math

Mere Array

constructive algorithms, math, number theory, sortings

Queue

greedy, implementation, sortings

Polygon

dp, graphs, implementation, shortest paths

Alice, Bob and Candies

implementation

Jzzhu and Sequences

implementation, math

Trouble Sort

constructive algorithms, implementation

Omkar and Last Class of Math

greedy, math, number theory

Anti-Sudoku

constructive algorithms, implementation

Number of Pairs

binary search, data structures, math, two pointers

Little Girl and Game

games, greedy

Queries about less or equal elements

binary search, data structures, sortings, two pointers

K-th Beautiful String

binary search, brute force, combinatorics, implementation, math

Dreamoon and WiFi

bitmasks, brute force, combinatorics, dp, math, probabilities

Buying Shovels

math, number theory

Product of Three Numbers

greedy, math, number theory

Random Teams

combinatorics, constructive algorithms, greedy, math

Pashmak and Flowers

combinatorics, implementation, sortings

Sort the Array

implementation, sortings

Cut Ribbon

brute force, dp

T-primes

binary search, implementation, math, number theory

Registration System

data structures, hashing, implementation

IQ test

brute force