Karen and Neighborhood

binary search, constructive algorithms, implementation

Karen and Cards

binary search, combinatorics, data structures, geometry

Karen and Supermarket

brute force, dp, trees

Karen and Test

brute force, combinatorics, constructive algorithms, math

Karen and Game

brute force, greedy, implementation

An unavoidable detour for home

combinatorics, dp, graphs, shortest paths

An overnight dance in discotheque

dfs and similar, dp, geometry, greedy, trees

An impassioned circulation of affection

brute force, dp, strings, two pointers

An express train to reveries

constructive algorithms

An abandoned sentiment from past

constructive algorithms, greedy, implementation, sortings

Bipartite Checking

data structures, dsu, graphs

Army Creation

binary search, data structures

Two Melodies

dp, flows

The Tag Game

dfs and similar, graphs

The Golden Age

brute force, math

The Contest

implementation

Sagheer and Apple Tree

games, trees

Sagheer and Kindergarten

dfs and similar, graphs, implementation, trees

Sagheer and Nubian Market

binary search, sortings

Sagheer, the Hausmeister

bitmasks, brute force, dp

Sagheer and Crossroads

implementation

Vladik and Entertaining Flags

data structures, dsu, graphs

Vladik and Favorite Game

constructive algorithms, dfs and similar, graphs, interactive

Vladik and Memorable Trip

dp, implementation

Vladik and Complicated Book

implementation, sortings

Vladik and Courtesy

brute force, implementation

Summer sell-off

greedy, sortings

Straight <<A>>

implementation, math

Surprise me!

divide and conquer, math, number theory, trees

Hitchhiking in the Baltic States

data structures, dp

Find a car

combinatorics, divide and conquer, dp

Glad to see you!

binary search, interactive

Do you want a date?

implementation, math, sortings

Anthem of Berland

dp, strings

Card Game

binary search, flows, graphs

Selling Souvenirs

binary search, dp, greedy, ternary search

Array Division

binary search, data structures, implementation

Tea Party

constructive algorithms, greedy, sortings

Average Sleep Time

data structures, implementation, math

Lucky Year

implementation

T-Shirt Hunt

brute force, implementation

Is it rated?

implementation, sortings

3-palindrome

constructive algorithms

Fake NP

greedy, math

Fake bullions

combinatorics, dfs and similar, dp, graphs, number theory

The same permutation

constructive algorithms

Expected diameter of a tree

binary search, brute force, dfs and similar, dp, sortings, trees

Ice cream coloring

constructive algorithms, dfs and similar, greedy

Minimum number of steps

combinatorics, greedy, implementation, math

Find Amir

constructive algorithms, greedy, math

Periodic RMQ Problem

data structures

Coprime Subsequences

bitmasks, combinatorics, number theory

Roma and Poker

dp, graphs

Magazine Ad

binary search, greedy

Maximal GCD

constructive algorithms, greedy, math

Distances to Zero

constructive algorithms

Maximal Binary Matrix

constructive algorithms

April Fools' Problem (hard)

binary search, data structures, flows

April Fools' Problem (medium)

binary search, flows, graphs

April Fools' Problem (easy)

greedy, sortings

Send the Fool Further! (hard)

dfs and similar, dp, math, trees

Send the Fool Further! (medium)

dp, trees

Send the Fool Further! (easy)

dfs and similar, graphs, trees

Fake News (hard)

string suffix structures

Fake News (medium)

constructive algorithms, strings

Fake News (easy)

implementation, strings

Marmots (hard)

math, probabilities

Marmots (medium)

math

Marmots (easy)

math

Heidi and Library (hard)

flows

Heidi and Library (medium)

data structures, greedy

Heidi and Library (easy)

greedy

Valued Keys

constructive algorithms, greedy, strings

Vicious Keyboard

brute force

Cut the pie

binary search, data structures, geometry

Beautiful fountains rows

data structures

Aquarium decoration

data structures, greedy, two pointers

Field expansion

brute force, dp, meet-in-the-middle

Fountains

binary search, data structures, implementation

T-shirt buying

data structures, implementation

Carrot Cakes

brute force, implementation

Mike and code of a permutation

constructive algorithms, data structures, graphs, sortings

Mike and distribution

constructive algorithms, sortings

Mike and gcd problem

dp, greedy, number theory

Mike and strings

brute force, dp, strings

Mike and palindrome

brute force, constructive algorithms, strings

Mice and Holes

data structures, dp, greedy, sortings

Array Queries

brute force, data structures, dp

Broken BST

data structures, dfs and similar

Minimal string

data structures, greedy, strings

Odd sum

dp, greedy, implementation

k-Factorization

implementation, math, number theory

Sequence Recovery

bitmasks, data structures, greedy

Exam Cheating

binary search, dp

Police Stations

constructive algorithms, dfs and similar, dp, graphs, shortest paths, trees

Bank Hacking

constructive algorithms, data structures, dp, trees

Find The Bone

implementation

Buying A House

brute force, implementation

Replace All

combinatorics, dp, math

Leha and security system

data structures