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

Choosing Carrot

games, math

Labelling Cities

dfs and similar, graphs, hashing

Naming Company

games, greedy, sortings

Cutting Carrot

geometry, math

Bank Robbery

brute force, implementation

Oleg and chess

data structures, divide and conquer, flows, graph matchings

Julia the snail

data structures, divide and conquer, dp

Problem of offices

constructive algorithms, dfs and similar, dp, trees

Presents in Bankopolis

dp, graphs, shortest paths

Mice problem

geometry, implementation, math, sortings

Igor and his way to work

dfs and similar, graphs, implementation, shortest paths

Oleg and shares

implementation, math

Mages and Monsters

data structures, geometry

Colored Balls

greedy, math, number theory

Paths in a Complete Binary Tree

bitmasks, trees

Divide by Three

dp, greedy, math, number theory

Counting-out Rhyme

implementation

New Bus Route

implementation, sortings

Bear and Big Brother

implementation

Masha and geometric depression

brute force, implementation, math

Anastasia and pebbles

implementation, math

New task

data structures

Finding lines

constructive algorithms, divide and conquer, interactive

The Great Mixing

dfs and similar, graphs, shortest paths

Weird journey

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

Functions again

dp, two pointers

Not Afraid

greedy, implementation, math

The Monster

brute force, math, number theory

ALT

data structures, flows, graphs, trees

Rap God

data structures, dfs and similar, hashing, strings, trees

Till I Collapse

data structures, divide and conquer

Legacy

data structures, graphs, shortest paths

Berzerk

dfs and similar, dp, games

Anton and Permutation

brute force, data structures

Anton and School - 2

combinatorics, dp, math, number theory

Anton and Fairy Tale

binary search, math

Anton and Classes

greedy, sortings

Anton and Polyhedrons

implementation, strings

BF Calculator

*special problem

Crunching Numbers Just for You

*special problem, implementation

Twisted Circuit

*special problem, brute force, implementation

Touchy-Feely Palindromes

*special problem, implementation

INTERCALC

*special problem, implementation

Kids' Riddle

*special problem

Numbers Joke

*special problem

Intranet of Buses

binary search, geometry, implementation, two pointers

Andryusha and Nervous Barriers

data structures, dp

Axel and Marston in Bitland

bitmasks, dp, graphs, matrices

Underground Lab

constructive algorithms, dfs and similar, graphs

Innokenty and a Football League

2-sat, graphs, greedy, implementation, shortest paths, strings

Andryusha and Colored Balloons

dfs and similar, graphs, greedy, trees

The Meeting Place Cannot Be Changed

binary search

Andryusha and Socks

implementation

Dishonest Sellers

constructive algorithms, greedy, sortings

Weird Rounding

brute force, greedy

Pupils Redistribution

constructive algorithms, math