Order Statistics

*special problem, binary search

Card Flip

*special problem

Best Runner

*special problem

Strong Connectivity Strikes Back

*special problem, constructive algorithms, graphs

Cute Subsequences

*special problem, sortings

Dreaming Is Not Harmful

*special problem

Arithmetic Exercise

*special problem, data structures, dp, greedy

Alice, Bob, And Two Arrays

*special problem, data structures, dp, games

Scammy Game Ad

dp, greedy

Vicious Labyrinth

constructive algorithms, graphs, greedy, implementation, math

Final Verdict

math

RGB Walking

bitmasks, chinese remainder theorem, dfs and similar, graphs, number theory

AND x OR

bitmasks, constructive algorithms, dp

Another Folding Strip

combinatorics, data structures, divide and conquer, dp, greedy, math

Maximum Polygon

brute force, data structures, implementation, math

Binary Subsequence Value Sum

combinatorics, data structures, dp, fft, math, matrices

Finding OR Sum

bitmasks, constructive algorithms, implementation, interactive, math

Breach of Faith

constructive algorithms, greedy, math, sortings

Game With Triangles: Season 2

dp, geometry

Counting Necessary Nodes

bitmasks, divide and conquer, geometry, greedy, implementation, math

Empty Triangle

geometry, interactive, probabilities

Counting Points

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

XOR and Triangle

bitmasks, brute force, geometry, greedy, probabilities

The Third Side

geometry, greedy, math

Draw a Square

geometry, implementation

Can You Reach There?

Boarding Queue

Book Sorting

Gathering Sharks

Squares on Grid Lines

Secret Lilies and Roses

interactive

Corrupted File

Hold the Star

Minus Operator

interactive

Tower of Hanoi

Cactus Connectivity

Three-Dimensional Embedding

Control Towers

I've Been Flipping Numbers for 300 Years and Calculated the Sum

binary search, brute force, combinatorics, divide and conquer, math, number theory

Goodbye, Banker Life

2-sat, bitmasks, combinatorics, constructive algorithms, fft, math, number theory

Do You Love Your Hero and His Two-Hit Multi-Target Attacks?

binary search, brute force, constructive algorithms, dp, geometry, greedy, math

For Wizards, the Exam Is Easy, but I Couldn't Handle It

brute force, greedy, implementation

Creating Keys for StORages Has Become My Main Skill

bitmasks, constructive algorithms, greedy

Having Been a Treasurer in the Past, I Help Goblins Deceive

combinatorics, constructive algorithms, strings

New World, New Me, New Array

greedy, implementation, math

Towering Arrays

binary search, data structures

LeaFall

combinatorics, dp, probabilities, trees

Infinite Sequence (Hard Version)

bitmasks, brute force, constructive algorithms, data structures, dp, implementation, math

Infinite Sequence (Easy Version)

bitmasks, brute force, dp, implementation, math

Trapmigiano Reggiano

constructive algorithms, data structures, dfs and similar, dp, greedy, sortings, trees

Perfecto

brute force, constructive algorithms, greedy, math

The Play Never Ends

math, number theory

Friends and Pizza

bitmasks, divide and conquer, dp, fft

Game with Binary String

constructive algorithms, data structures, divide and conquer, games, greedy, math

Tree Jumps

dfs and similar, dp, trees

Limited Repainting

binary search, greedy

Robot Program

brute force, implementation, math

FizzBuzz Remixed

brute force, math

Graph Inclusion

data structures, dfs and similar, divide and conquer, dsu, graphs

A, B, AB and BA

constructive algorithms, greedy, sortings, strings

Palindrome Shuffle

binary search, greedy, hashing, strings, two pointers

Beautiful Sequence

combinatorics, dp, greedy, two pointers

Set of Strangers

greedy, matrices

Was there an Array?

graph matchings, greedy

Amusement Park Rides

flows, graphs

The Ultimate Wine Tasting Event

combinatorics, greedy

Pinball

graphs, shortest paths

Statues

constructive algorithms, greedy, math

A Very Long Hike

shortest paths

Mascot Naming

brute force, greedy, implementation, strings

Porto Vs. Benfica

data structures, dfs and similar, dsu, graphs, shortest paths

Morse Code

dp, sortings, trees

Ads

binary search, greedy, two pointers

Urban Planning

constructive algorithms

Condorcet Elections

constructive algorithms, graphs, greedy, probabilities

Devyatkino

brute force, dfs and similar, greedy, math

Two Large Bags

brute force, dp, greedy, sortings

Adjacent Digit Sums

brute force, constructive algorithms, math

Curse

constructive algorithms, dp, math

Tropical Season

binary search, data structures, greedy, implementation

Club of Young Aircraft Builders (hard version)

combinatorics, dp, math

Club of Young Aircraft Builders (easy version)

combinatorics, dp, math

Bitwise Slides

bitmasks, combinatorics, dp, math

White Magic

constructive algorithms, data structures, dp, greedy, implementation

Object Identification

graphs, greedy, implementation, interactive

Bro Thinks He's Him

combinatorics, data structures, divide and conquer, dp, math, matrices

Skibidus and Capping

combinatorics, math, number theory

Skibidus and Slay

data structures, dfs and similar, graphs, greedy, trees

Skibidus and Rizz

constructive algorithms, greedy, strings

Skibidus and Sigma

greedy, sortings

Skibidus and Fanum Tax (hard version)

binary search, greedy

Skibidus and Fanum Tax (easy version)

binary search, dp, greedy

Skibidus and Ohio

strings

Skibidus and Amog'u

brute force, constructive algorithms, greedy, implementation, strings

We Be Summing

binary search, data structures, dp, two pointers

Mycraft Sand Sort

combinatorics, data structures, dsu, greedy, math, sortings

Eating

binary search, bitmasks, brute force, data structures, dp, greedy, trees, two pointers

Remove the Ends

brute force, constructive algorithms, dp, greedy

Variety is Discouraged

binary search, constructive algorithms, greedy, two pointers

Brogramming Contest

greedy, strings