Snowball

implementation

Ж-function

string suffix structures, strings

Fedya the Potter

binary search, implementation, math, number theory

Eels

data structures

Construct a tree

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

Nice table

brute force, constructive algorithms, greedy, math

Sum in the tree

constructive algorithms, dfs and similar, greedy, trees

Mateusz and an Infinite Sequence

bitmasks, brute force, dp, strings

Vladislav and a Great Legend

combinatorics, dp, trees

Alex and a TV Show

bitmasks, combinatorics, number theory

Egor and an RPG game

constructive algorithms, greedy

Makoto and a Blackboard

dp, math, number theory, probabilities

Yuhao and a Parenthesis

greedy, implementation

Petr and a Combination Lock

bitmasks, brute force, dp

Gennady and a Card Game

brute force, implementation

Lucky Tickets

divide and conquer, dp, fft

Inversion Expectation

dp, math, probabilities

The Top Scorer

combinatorics, dp, math, probabilities

Easy Problem

dp

Polygon for the Angle

brute force, geometry

Substring Removal

combinatorics, math, strings

Find Divisible

greedy, implementation, math

Make It Connected

dsu, graphs, greedy

Almost Regular Bracket Sequence

implementation

Circular Dance

implementation

Powers Of Two

bitmasks, greedy

Array Stabilization

implementation

Repeating Cipher

implementation

Multidimensional Queries

bitmasks, data structures

Vasya and Array

dp

Intersection of Permutations

data structures

Beautiful Graph

dfs and similar, graphs

Mishka and the Last Exam

greedy

Letters Rearranging

constructive algorithms, greedy, sortings, strings

Dice Rolling

math

Tree with Maximum Cost

dfs and similar, dp, trees

Minimal Diameter Forest

constructive algorithms, dfs and similar, greedy, trees

Great Vova Wall (Version 2)

data structures, implementation

Great Vova Wall (Version 1)

greedy, implementation, math

Prefixes and Suffixes

strings

Teams Forming

sortings

Uniform String

implementation

New Year and the Tricolore Recreation

games

New Year and the Factorisation Collaboration

interactive, math, number theory

New Year and the Mallard Expedition

constructive algorithms, greedy

New Year and the Acquaintance Estimation

binary search, data structures, graphs, greedy, implementation, math, sortings

New Year and the Permutation Concatenation

combinatorics, dp, math

New Year and the Sphere Transmission

math, number theory

New Year and the Treasure Geolocation

brute force, constructive algorithms, greedy, implementation

New Year and the Christmas Ornament

brute force, implementation, math

The Pleasant Walk

implementation

Berland University

greedy, math

Right Expansion Of The Mind

math

Two Prefixes

strings

Minimal Product

Linearization

graphs

Combostone

games, implementation

How to Learn You Score

constructive algorithms, interactive

Horseback Riding

flows, graphs

Similar Arrays

constructive algorithms

New Year Presents

constructive algorithms, data structures

LaTeX Expert

Company Merging

greedy

Minegraphed

constructive algorithms, graphs

Lazyland

King Kog's Reception

data structures

JS Minification

greedy, implementation

Interval-Free Permutations

combinatorics

Harder Satisfiability

2-sat, dfs and similar, graphs

Guest Student

math

Fractions

math

Easy Chess

constructive algorithms

Distance Sum

graphs

Cactus Search

interactive

Bimatching

graphs

Alice the Fan

dp

Ehab and a weird weight formula

data structures, trees

Ehab and a component choosing problem

dp, greedy, math, trees

Ehab and another another xor problem

bitmasks, constructive algorithms, implementation, interactive

Ehab and a 2-operation task

constructive algorithms, greedy, math

Ehab and subtraction

implementation, sortings

Ehab and another construction problem

brute force, constructive algorithms

Forest Fires

math

Beautiful Matrix

combinatorics, data structures, dp

Rock-Paper-Scissors Champion

Vasya and Templates

greedy, implementation, strings

Minimum Diameter Tree

constructive algorithms, implementation, trees

Connect Three

implementation, math

Div Times Mod

math

Right-Left Cipher

implementation, strings

The Fair Nut and String

combinatorics, dp, implementation

Kvass and the Fair Nut

greedy, implementation

The Fair Nut and Elevator

brute force, implementation

The Fair Nut and Amusing Xor

data structures

The Fair Nut and Rectangles

data structures, dp, geometry

The Fair Nut's getting crazy

data structures, implementation

Max Mex

data structures, trees

The Fair Nut and Strings

greedy, strings

The Fair Nut and the Best Path

data structures, dp, trees

Petya and Graph

flows, graphs