Wooden Raft

binary search, math, number theory

Stack Exterminable Arrays

data structures, divide and conquer, dp, hashing

Paint the Tree

dp, sortings, trees

Sequence Sorting

dp, greedy, two pointers

Save the Nature

binary search, greedy

Graph And Numbers

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

Choose a Square

binary search, data structures, sortings

Game With String

games

Make The Fence Great Again

dp

Geolocation

geometry

Gardener Alex

binary search, data structures

Tourism

dfs and similar, dp, dsu, graphs, greedy, trees

Alex and Julian

bitmasks, math, number theory

Harvester

implementation

Periodic integer number

implementation, strings

The Light Square

2-sat, dfs and similar, greedy

Function Composition

dfs and similar

Alpha planetary system

constructive algorithms, graphs, shortest paths

Product Tuples

divide and conquer, fft

Xor Spanning Tree

divide and conquer, fft, graphs

Jumping Transformers

dp

Guarding warehouses

data structures, geometry

BubbleReactor

dp, graphs

Forced Online Queries Problem

data structures, divide and conquer, dsu, graphs, trees

Sum Queries?

data structures, greedy, implementation, math

Coloring Edges

constructive algorithms, dfs and similar, graphs

The Number Of Good Substrings

binary search, bitmasks, brute force

Zmei Gorynich

greedy, math

Wi-Fi

data structures, dp, greedy

Numerical Sequence (hard version)

binary search, math

Numerical Sequence (easy version)

binary search, brute force, math

White Sheet

geometry, math

Radio Stations

2-sat

Marbles

bitmasks, dp

Ticket Game

games, greedy, math

Tiles Placement

constructive algorithms, dfs and similar, trees

Feeling Good

bitmasks, data structures

Employment

greedy, sortings

Petya and Construction Set

constructive algorithms, graphs, math, sortings, trees

Treasure Island

dfs and similar, dp, flows, hashing

Path Queries

divide and conquer, dsu, graphs, sortings, trees

Unstable String Sort

data structures, dfs and similar, dsu, graphs, greedy, implementation, strings

Two Small Strings

brute force, constructive algorithms

Equalizing by Division (hard version)

brute force, math, sortings

Unusual Graph

*special problem, graphs

Road Repair in Treeland

*special problem, binary search, dp, trees

King's Path

*special problem, math, trees

kotlinkotlinkotlinkotlin...

*special problem, graphs, implementation, strings

Double Permutation Inc.

*special problem, binary search, greedy

Teams

*special problem, binary search, greedy, math

Ice Cream

*special problem, greedy, sortings

Mateusz and Escape Room

dp

Marek and Matching (hard version)

brute force, probabilities

Marek and Matching (easy version)

brute force, probabilities

Wojtek and Card Tricks

math

Konrad and Company Evaluation

graphs

Kamil and Making a Stream

math, number theory, trees

Marcin and Training Camp

brute force, greedy

Anadi and Domino

brute force, graphs

Moving Walkways

data structures, greedy, math

Into Blocks (hard version)

data structures

Into Blocks (easy version)

data structures, dsu, greedy, implementation, two pointers

Koala and Notebook

data structures, dfs and similar, graphs, shortest paths, strings, trees

Rotate Columns (hard version)

bitmasks, dp, greedy, sortings

Rotate Columns (easy version)

bitmasks, brute force, dp, greedy, sortings

Cow and Snacks

dfs and similar, dsu, graphs

Red Blue Tree

data structures, implementation, trees

Polygons

greedy, math, number theory

Bits And Pieces

bitmasks, dfs and similar, dp, greedy

Let Them Slide

data structures, implementation

Restore Permutation

binary search, data structures, greedy, implementation

Magic Grid

constructive algorithms

Indie Album

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

Remainder Problem

brute force, data structures, implementation

XOR Guessing

bitmasks, interactive, math

Number Of Permutations

combinatorics

Beauty of a Permutation

constructive algorithms, math

Expected Value Again

combinatorics, strings

Almost All

constructive algorithms, trees

Palindromic Paths

implementation, interactive

Shortest Cycle

bitmasks, brute force, graphs, shortest paths

Natasha, Sasha and the Prefix Sums

combinatorics, dp, math, number theory

Kirk and a Binary String (hard version)

data structures, greedy, math, strings

Kirk and a Binary String (easy version)

brute force, greedy, strings

Anna, Svyatoslav and Maps

dp, graphs, greedy, shortest paths

Complete the Projects (hard version)

dp, greedy

Complete the Projects (easy version)

greedy

Remove the Substring (hard version)

binary search, greedy, implementation, two pointers

Remove the Substring (easy version)

greedy, implementation

You Are Given Some Letters...

binary search, implementation, math

You Are Given Some Strings...

brute force, string suffix structures, strings

Print a 1337-string...

combinatorics, constructive algorithms, math, strings

You Are Given a WASD-string...

brute force, data structures, dp, greedy, implementation, math, strings

You Are Given a Decimal String...

brute force, dp, shortest paths

Knightmare (hard)

graphs, interactive, shortest paths

Knightmare (easy)

graphs, interactive, shortest paths

Treasure Hunting

binary search, dp, greedy, implementation

Graph Traveler

brute force, data structures, dfs and similar, dp, graphs, implementation, math, number theory

Compress Words

brute force, hashing, implementation, string suffix structures, strings

White Lines

brute force, data structures, dp, implementation, two pointers