Sum Over Subsets

combinatorics, math, number theory

Complicated Computations

binary search, data structures, two pointers

Bandit in a City

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

Binary Search

binary search, combinatorics

Prime Square

constructive algorithms, math

Reorder

math

A Convex Game

dsu, games

Reducing Delivery Cost

brute force, graphs, shortest paths

Zero Remainder Sum

dp

Two Round Dances

combinatorics, math

Districts Connection

constructive algorithms, dfs and similar

Dominant Piranha

constructive algorithms, greedy

Yet Another Bookshelf

greedy, implementation

Boring Apartments

implementation, math

Zero-XOR Array

*special problem, dp

Cyclic Shifts

*special problem, strings

Rogue-like Game

*special problem, brute force, greedy, two pointers

Number Deletion Game

*special problem, dp, games, greedy

Neural Network Problem

*special problem, binary search, greedy

Chess Match

*special problem

Used Markers

*special problem, greedy

Black Friday

*special problem, implementation

Polycarp and the Language of Gods

*special problem, implementation, two pointers

Selling Hamburgers

*special problem

Yet Another DAG Problem

bitmasks, dfs and similar, dp, flows, graphs, math

Realistic Gameplay

dp, greedy

String Reversal

data structures, greedy, strings

String Deletion

binary search, data structures, greedy, two pointers

Numbers on Whiteboard

constructive algorithms, data structures, greedy, implementation, math

Barrels

greedy, implementation, sortings

Number of Apartments

brute force, constructive algorithms, math

Rotary Laser Lock

binary search, interactive

Lucky Numbers (Hard Version)

dp, greedy

Lucky Numbers (Easy Version)

dp, greedy

Fruit Sequences

binary search, data structures, divide and conquer, dp, two pointers

Carrots for Rabbits

binary search, data structures, greedy, math, sortings

Bouncing Boomerangs

constructive algorithms, greedy, implementation

ABBB

brute force, data structures, greedy, strings

Belted Rooms

graphs, implementation

Box is Pull

math

Prison Break

binary search, games, geometry, ternary search

One Billion Shades of Grey

flows, graphs

Boring Card Game

data structures, greedy, trees

Xum

bitmasks, constructive algorithms, math, matrices, number theory

Unshuffling a Deck

constructive algorithms, implementation

The Hard Work of Paparazzi

dp

Chess Cheater

greedy, implementation, sortings

Avoiding Zero

math, sortings

Number of Subsequences

combinatorics, dp, strings

Rock, Paper, Scissors

brute force, constructive algorithms, flows, greedy, math

Non-zero Segments

constructive algorithms, data structures, greedy, sortings

Increase and Copy

binary search, constructive algorithms, math

Symmetric Matrix

implementation

Floor Number

implementation, math

Impressive Harvesting of The Orchard

data structures

Huge Boxes of Animal Toys

constructive algorithms

Flamingoes of Mystery

interactive

Excitation of Atoms

greedy, implementation

Danger of Mad Snakes

combinatorics, dp, math

Captain of Knights

math

Blue and Red of Our Faculty!

divide and conquer, dp

Arena of Greed

games, greedy

Ancient Language

graphs, sortings

Years

data structures, sortings

BubbleSquare Tokens

Milutin's Plums

interactive

Light switches

meet-in-the-middle

Lonely Numbers

binary search, math, number theory, two pointers

Bubble Cup hypothesis

bitmasks, constructive algorithms, dp, math

Lookup Tables

bitmasks

Virus

data structures, divide and conquer, dsu, graphs

Growing flowers

data structures

Coins

math

5G Antenna Towers

geometry

Does anyone else hate the wind?

Dušan's Railway

divide and conquer, graphs, trees

Valuable Paper

binary search, flows, graph matchings, graphs

Wakanda Forever

Boring Queries

data structures, math, number theory

Minlexes

dp, greedy, implementation, strings

Returning Home

graphs, shortest paths, sortings

Bargain

combinatorics, dp, math

Nice Matrix

greedy, implementation, math

Fence

geometry, math

Swedish Heroes

brute force, dp, implementation

Hexagons

brute force, constructive algorithms, greedy, implementation, math, shortest paths

Palindromifier

constructive algorithms, strings

Putting Bricks in the Wall

constructive algorithms, implementation

XORwice

bitmasks, greedy, math

Battle Lemmings

dp, greedy

Rescue Nibel!

combinatorics, data structures, sortings

Pokémon Army (hard version)

data structures, divide and conquer, dp, greedy, implementation

Pokémon Army (easy version)

constructive algorithms, dp, greedy

Rock and Lever

bitmasks, math

Cubes Sorting

math, sortings

Rain of Fire

binary search, data structures, dfs and similar, dsu, graphs, implementation

Decryption

constructive algorithms, implementation, math, number theory

Sage's Birthday (hard version)

binary search, brute force, constructive algorithms, greedy, sortings, two pointers

Sage's Birthday (easy version)

binary search, constructive algorithms, greedy, sortings

Killjoy

greedy, implementation, math