Try Booking

data structures, divide and conquer

Favorite Game

bitmasks, dp

Crypto Lights

combinatorics, dp, math, probabilities

Love-Hate

bitmasks, brute force, dp, probabilities

Compression and Expansion

brute force, data structures, greedy, implementation, trees

Lord of the Values

constructive algorithms

Game of Life

implementation

Nastia and a Beautiful Matrix

binary search, constructive algorithms, dp, greedy

Nastia Plays with a Tree

constructive algorithms, data structures, dfs and similar, dp, dsu, greedy, implementation, trees

Nastia and a Hidden Permutation

constructive algorithms, interactive

Nastia and a Good Array

constructive algorithms, math, number theory

Nastia and Nearly Good Numbers

constructive algorithms, math, number theory

To Go Or Not To Go?

brute force, dfs and similar, graphs, greedy, implementation, shortest paths

Guess the K-th Zero (Hard version)

binary search, constructive algorithms, data structures, interactive

Guess the K-th Zero (Easy version)

binary search, interactive

Arranging The Sheep

greedy, math

Same Differences

data structures, hashing, math

Not Adjacent Matrix

constructive algorithms

Ordinary Numbers

brute force, math, number theory

Do Not Be Distracted!

brute force, implementation

Chests and Keys

bitmasks, brute force, dfs and similar, dp, flows

Off by One

constructive algorithms, dfs and similar, geometry, graphs, sortings, trees

Maximum Sum of Products

brute force, dp, implementation, math, two pointers

Berland Regional

brute force, data structures, greedy, number theory, sortings

The Cake Is a Lie

dp, math

Red and Blue Beans

math

Fly Around the World

dp, geometry

Starry Night Camping

constructive algorithms, flows, graphs

Reunion

combinatorics, dp, trees

Group Photo

binary search, data structures, implementation, two pointers

Explorer Space

dp, graphs, shortest paths

Fillomino 2

constructive algorithms, dfs and similar, greedy, implementation

Morning Jogging

constructive algorithms, greedy, sortings

Sum of 2050

greedy, math

Baby Ehab Plays with Permutations

combinatorics, dp, math

Cut

binary search, data structures, dp, graphs, number theory, two pointers

Baby Ehab Partitions Again

bitmasks, constructive algorithms, dp, math

AGAGA XOOORRR

bitmasks, brute force, dp, greedy

Tit for Tat

greedy

Phoenix and Diamonds

binary search, data structures, sortings

Phoenix and Bits

bitmasks, brute force, data structures, sortings

Phoenix and Odometers

dfs and similar, graphs, math, number theory

Phoenix and Earthquake

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

Phoenix and Computers

combinatorics, dp, math

Phoenix and Socks

greedy, sortings, two pointers

Phoenix and Towers

constructive algorithms, data structures, greedy

Phoenix and Puzzle

brute force, geometry, math, number theory

Phoenix and Gold

constructive algorithms, greedy, math

Baby Ehab's Hyper Apartment

binary search, graphs, interactive, sortings, two pointers

Cut and Stick

binary search, data structures, greedy, implementation, sortings

Product 1 Modulo N

greedy, number theory

AND 0, Sum Big

bitmasks, combinatorics, math

Perfectly Imperfect Array

math, number theory

Swapping Problem

brute force, constructive algorithms, data structures, sortings

Cost Equilibrium

combinatorics, constructive algorithms, math, sortings

GCD and MST

constructive algorithms, dsu, graphs, greedy, number theory, sortings

Add One

dp, matrices

AND Sequences

bitmasks, combinatorics, constructive algorithms, math

Array and Peaks

constructive algorithms, implementation

Short Task

brute force, dp, math, number theory

Education

brute force, dp, greedy, implementation

Permutation by Sum

brute force, greedy, math

Corrupted Array

constructive algorithms, data structures, greedy

A-B Palindrome

constructive algorithms, implementation, strings

Almost Rectangle

implementation

Spy Detected!

brute force, implementation

Chips on a Board

bitmasks, brute force, data structures, dp, games, two pointers

Chainword

brute force, data structures, dp, matrices, string suffix structures, strings

Colorings and Dominoes

combinatorics, dp, greedy, math

Min Cost String

brute force, constructive algorithms, graphs, greedy, strings

Yet Another Card Deck

brute force, data structures, implementation, trees

GCD Length

constructive algorithms, math, number theory

Review Site

greedy

King's Task

brute force, graphs, implementation

Japanese Game

constructive algorithms, math

Is It Rated?

greedy, interactive, math, probabilities

Hard Optimization

dp

Guide

Fiber Shape

Equilibrium Point /\textbackslash/\textbackslash

Digits

dp, math, number theory

Cactus Not Enough

dfs and similar, graph matchings, graphs

Button Lock

flows, graph matchings, graphs

ASCII Automata Art

The Sports Festival

dp, greedy

TMT Document

greedy

Average Height

constructive algorithms

Optimal Encoding

brute force, data structures

Tree Calendar

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

Swap Pass

constructive algorithms, geometry, sortings

Complete the MST

bitmasks, brute force, data structures, dfs and similar, dsu, graphs, greedy, trees

Almost Sorted

binary search, combinatorics, constructive algorithms, implementation

Binary Literature

constructive algorithms, greedy, implementation, strings, two pointers

Maximize the Remaining String

brute force, data structures, dp, greedy, strings

Triangular Paths

constructive algorithms, graphs, math, shortest paths, sortings

Restoring the Permutation

constructive algorithms, implementation

Epic Transformation

constructive algorithms, data structures, greedy

Double-ended Strings

brute force, implementation, strings

Partial Replacement

greedy, implementation

Strange Table

math