Bad Cryptography

math, number theory

Strange Function

dp

Tourism

dp, graphs, probabilities

Au Pont Rouge

binary search, dp, strings

Double Elimination

dp, implementation

Recommendations

data structures, greedy, sortings

Cow and Exercise

flows, graphs, shortest paths

Cow and Vacation

dfs and similar, dsu, trees

Cow and Treats

binary search, combinatorics, dp, greedy, implementation, math

Cow and Fields

binary search, data structures, dfs and similar, graphs, greedy, shortest paths, sortings

Cow and Message

brute force, dp, math, strings

Cow and Friend

geometry, greedy, math

Cow and Haybales

greedy, implementation

Kuroni the Private Tutor

binary search, greedy

Kuroni and Antihype

bitmasks, brute force, dp, dsu, graphs

Kuroni and the Punishment

math, number theory, probabilities

Kuroni and the Score Distribution

constructive algorithms, greedy, implementation, math

Kuroni and the Celebration

constructive algorithms, dfs and similar, interactive, trees

Kuroni and Impossible Calculation

brute force, combinatorics, math, number theory

Kuroni and Simple Strings

constructive algorithms, greedy, strings, two pointers

Kuroni and the Gifts

brute force, constructive algorithms, greedy, sortings

Animal Observation (hard version)

data structures, dp, greedy

Animal Observation (easy version)

data structures, dp

1-Trees and Queries

data structures, dfs and similar, shortest paths, trees

Shortest and Longest LIS

constructive algorithms, graphs, greedy, two pointers

Air Conditioner

dp, greedy, implementation, sortings, two pointers

Longest Palindrome

brute force, constructive algorithms, greedy, implementation, strings

Two Rabbits

math

Sum of Prefix Sums

data structures, divide and conquer, geometry, trees

Number of Components

dsu, implementation

Erase Subsequences

dp, strings

Fill The Bag

bitmasks, greedy

Perfect Keyboard

dfs and similar, greedy, implementation

National Project

math

Erasing Zeroes

implementation, strings

Keep talking and nobody explodes -- hard

Deja vu

Who needs suffix structures?

Keep talking and nobody explodes -- medium

Keep talking and nobody explodes -- easy

bitmasks, brute force, expression parsing

Amazing bitset

Dijkstra

Segment tree or Fenwick?

data structures

DAG

constructive algorithms

Nash equilibrium

Super Jaber

dfs and similar, graphs, implementation, shortest paths

Nanosoft

binary search, data structures, dp, implementation

Time to Run

constructive algorithms, graphs, implementation

Ayoub's function

binary search, combinatorics, greedy, math, strings

Motarack's Birthday

binary search, greedy, ternary search

Three Strings

implementation, strings

Assigning to Classes

greedy, implementation, sortings

Non-zero

implementation, math

So Mean

interactive, math

Around the World

bitmasks, combinatorics, dfs and similar, dp, graphs, math, trees

Water Balance

data structures, geometry, greedy

Aerodynamic

geometry

Anu Has a Function

brute force, greedy, math

Falling Blocks

*special problem, data structures

Paint the String

*special problem, dp, strings

M-numbers

*special problem, dp, math

Movie Fan

*special problem, data structures, greedy, implementation, sortings

Modernization of Treeland

*special problem, dfs and similar, trees

Bonus Distribution

*special problem, binary search, greedy, sortings

Dream Team

*special problem, greedy

Cartoons

*special problem, implementation, sortings

Likes Display

*special problem, implementation

Berland Beauty

constructive algorithms, dfs and similar, greedy, sortings, trees

String Coloring (hard version)

data structures, dp

String Coloring (easy version)

constructive algorithms, dp, graphs, greedy, sortings

Fight with Monsters

greedy, sortings

Yet Another Walking Robot

data structures, implementation

Food Buying

math

Array with Odd Sum

math

Good Contest

combinatorics, dp, probabilities

Permutation Separation

data structures, divide and conquer

Same GCDs

math, number theory

Obtain The String

dp, greedy, strings

Infinite Prefixes

math, strings

Display The Number

greedy

Three Paths on a Tree

dfs and similar, dp, greedy, trees

Obtain a Permutation

greedy, implementation, math

MEX maximizing

data structures, greedy, implementation, math

Product of Three Numbers

greedy, math, number theory

Collecting Packages

implementation, sortings

Collecting Coins

math

JOE is on TV!

combinatorics, greedy, math

ConneR and the A.R.C. Markland-N

binary search, brute force, implementation

Nora's Toy Boxes

bitmasks, combinatorics, dp

Rin and The Unknown Flower

constructive algorithms, greedy, interactive, math

Chaotic V.

dp, graphs, greedy, math, number theory, trees

Xenon's Attack on the Gangs

combinatorics, dfs and similar, dp, greedy, trees

Aroma's Search

brute force, constructive algorithms, geometry, greedy, implementation

NEKO's Maze Game

data structures, dsu, implementation

Coffee Varieties (easy version)

graphs, interactive

Array Sharpening

greedy, implementation

Even But Not Even

greedy, math, strings

Making Shapes

dp

Cartesian Tree

data structures

Coffee Varieties (hard version)

constructive algorithms, graphs, interactive