Farmer John's Challenge

constructive algorithms, math

Rudolf and Subway

constructive algorithms, dfs and similar, graphs, shortest paths

Rudolf and Imbalance

binary search, greedy, sortings, two pointers

Rudolf and k Bridges

binary search, data structures, dp, two pointers

Rudolf and the Ball Game

dfs and similar, dp, implementation

Rudolf and the Ugly String

dp, greedy, strings

Rudolf and 121

brute force, dp, greedy, math

Rudolf and the Ticket

brute force, math

Almost Certainly

*special problem, constructive algorithms, data structures, sortings

Burenka and Pether

*special problem, data structures, dfs and similar, divide and conquer, dsu, graphs, sortings, trees

Three Arrays

*special problem, constructive algorithms, implementation, sortings

Parallel Universes

*special problem, constructive algorithms, dfs and similar, dsu, graphs

Big Persimmon

*special problem, dp, games

More Gifts

*special problem, dfs and similar, two pointers

Evidence Board

*special problem, constructive algorithms, dfs and similar, graphs, trees

Draw Polygon Lines

*special problem, constructive algorithms, dp, geometry, interactive

Zig-zag

XOR Operations

Tree Quiz

There and Back Again

Symmetric Boundary

Pho Restaurant

Personality Test

Forming Groups

Duplicates

Bánh Bò

Bit Counting Sequence

Attraction Score

Antiparticle Antiphysics

Binary Path

dp, greedy, implementation

Shuffle Party

implementation, math

Grand Finale: Circles

binary search, geometry

Yet Yet Another Permutation Problem

divide and conquer, fft, math

Bitwise Paradox

binary search, bitmasks, data structures, greedy, two pointers

Pokémon Arena

data structures, graphs, greedy, implementation, shortest paths, sortings

Pinball

binary search, data structures, implementation, math, two pointers

Bitwise Operation Wizard

bitmasks, constructive algorithms, greedy, interactive, math

Andrey's Tree

binary search, constructive algorithms, data structures, dfs and similar, dsu, greedy, implementation, trees

Distance Learning Courses in MAC

bitmasks, brute force, data structures, greedy, math

Exam in MAC

binary search, combinatorics, implementation, math

Messenger in MAC

binary search, brute force, constructive algorithms, data structures, dp, greedy, sortings

Informatics in MAC

constructive algorithms

Entertainment in MAC

constructive algorithms, strings

Weird LCM Operations

brute force, constructive algorithms, number theory

XOR Break --- Game Version

bitmasks, games, greedy, interactive

XOR Break --- Solo Version

bitmasks, constructive algorithms, greedy

Find a Mine

binary search, constructive algorithms, geometry, greedy, interactive, math

Yet Another Coin Problem

brute force, dp, greedy, math

Too Min Too Max

greedy, math

Turtle Magic: Royal Turtle Shell Pattern

bitmasks, brute force, combinatorics, constructive algorithms, dfs and similar, math

Turtle Mission: Robot and the Earthquake

dfs and similar, dp, graphs, shortest paths

Turtle vs. Rabbit Race: Optimal Trainings

binary search, implementation, math, ternary search

Turtle Tenacity: Continual Mods

constructive algorithms, greedy, math, number theory, sortings

Turtle Fingers: Count the Values of k

brute force, implementation, math, number theory

Turtle Math: Fast Three Task

implementation, math, number theory

Turtle Puzzle: Rearrange and Negate

greedy, math, sortings

Moving Platforms

graphs, math, number theory, shortest paths

Feed Cats

data structures, dp, sortings

Final Countdown

implementation, math, number theory

Card Game

greedy, implementation

LR-remainders

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

Chaya Calendar

number theory

Thorns and Coins

dp, greedy, implementation

One-Dimensional Puzzle

combinatorics, math, number theory

Chat Screenshots

combinatorics, dfs and similar, graphs

Anna and the Valentine's Day Gift

games, greedy, math, sortings

Divisible Pairs

combinatorics, math, number theory

Make Equal Again

brute force, greedy, math

Make Equal

greedy

Recovering a Small String

brute force, strings

Counting Is Fun

combinatorics

Interactive Mex Tree

constructive algorithms, dfs and similar, interactive, trees

Prefix Max Set Counting

data structures, dp, trees

Maximize the Difference

bitmasks, brute force, dfs and similar

2..3...4.... Wonderful! Wonderful!

combinatorics, dp, math

Sum over all Substrings (Hard Version)

bitmasks, divide and conquer, dp, dsu, greedy, implementation, strings

Sum over all Substrings (Easy Version)

brute force, dp, greedy, strings

Lexicographically Largest

binary search, constructive algorithms, data structures, greedy, sortings

Permutation Printing

brute force, constructive algorithms, math

Maximise The Score

greedy, sortings

Sasha and the Wedding Binary Search Tree

brute force, combinatorics, data structures, dfs and similar, math, trees

Sasha and the Happy Tree Cutting

bitmasks, brute force, dfs and similar, dp, graphs, greedy, math, trees

Sasha and a Walk in the City

combinatorics, dp, math, trees

Sasha and the Casino

binary search, brute force, constructive algorithms, games, greedy, math

Sasha and the Drawing

constructive algorithms, greedy, math

Sasha and the Beautiful Array

constructive algorithms, greedy, math, sortings

Digital Patterns

combinatorics, data structures, implementation, math

Modular Sequence

brute force, constructive algorithms, dp, graphs, greedy, math, number theory

Lonely Mountain Dungeons

brute force, data structures, greedy, math, ternary search

Physical Education Lesson

brute force, math, number theory

Equalize

binary search, greedy, sortings, two pointers

Rectangle Cutting

geometry, math

Paint Charges

data structures, dp, greedy, math

Microcycle

data structures, dfs and similar, dsu, graphs, greedy, implementation, sortings, trees

Klever Permutation

constructive algorithms, math, two pointers

Find the Different Ones!

binary search, brute force, data structures, dp, dsu, greedy, two pointers

Choose the Different Ones!

brute force, greedy, math

Following the String

constructive algorithms, greedy, strings

Make it White

greedy, strings

Vlad and Trouble at MIT

dfs and similar, dp, flows, graphs, greedy, implementation, trees