Construct Matrix

constructive algorithms, math

Boxes and Balls

dp, implementation, math

Xum

bitmasks, constructive algorithms, math, matrices, number theory

Removing Graph

brute force, dp, games, graphs, math

Tokitsukaze and Permutations

dp, math

LCM Sum (hard version)

brute force, data structures, math, number theory, two pointers

Sports Betting

bitmasks, combinatorics, dp, graphs, math, probabilities

Two Arithmetic Progressions

math, number theory

Nene vs. Monsters (Easy Version)

brute force, implementation, math

New Year and Castle Construction

combinatorics, geometry, math, sortings

Rare Coins

combinatorics, math, probabilities

Cow and Treats

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

Colored Balls

greedy, math, number theory

Gojou and Matrix Game

data structures, dp, games, hashing, implementation, math, number theory, sortings

Bags with Balls

combinatorics, dp, math, number theory

Necklace

constructive algorithms, math

Curious Array

brute force, combinatorics, implementation, math

Maximum Reduction

combinatorics, data structures, math

Narrow Components

brute force, data structures, dp, dsu, math, trees

K-Set Tree

combinatorics, dfs and similar, dp, math, trees

Lottery

binary search, brute force, greedy, math, two pointers

In Search of Truth (Hard Version)

constructive algorithms, interactive, math, meet-in-the-middle, probabilities

Ela Goes Hiking

combinatorics, dp, math, probabilities

Points

combinatorics, data structures, implementation, math, matrices

Coloring

combinatorics, constructive algorithms, implementation, math

The Top Scorer

combinatorics, dp, math, probabilities

Case of a Top Secret

binary search, implementation, math

The Boss's Identity

binary search, bitmasks, data structures, dfs and similar, greedy, math, sortings

Christmas Game

bitmasks, data structures, dfs and similar, dp, games, math, trees

DSU Master

combinatorics, dp, dsu, math

Expected Square Beauty

dp, math, probabilities

Algebra Flash

bitmasks, brute force, dp, graphs, math, meet-in-the-middle, trees

Small Permutation Problem (Hard Version)

combinatorics, dp, math

Balancing Weapons

binary search, brute force, data structures, math, two pointers

The Tree Has Fallen!

bitmasks, dfs and similar, math, trees

Baby Ehab Plays with Permutations

combinatorics, dp, math

The Neutral Zone

brute force, math

Brukhovich and Exams

brute force, greedy, implementation, math, sortings

Zeros and Ones

bitmasks, divide and conquer, dp, math

Serval and Music Game

brute force, dp, implementation, math, number theory

Cowslip Collections

combinatorics, math, number theory

Game

math

Laboratory on Pluto

constructive algorithms, dp, greedy, math

New Year and Entity Enumeration

bitmasks, combinatorics, dp, math

More Queries to Array...

data structures, math

Geometers Anonymous Club

data structures, geometry, math, sortings

Even Split

binary search, constructive algorithms, greedy, math

Power or XOR?

bitmasks, combinatorics, math, number theory

Function Sum

brute force, combinatorics, dp, fft, math

Inverse Transformation

constructive algorithms, implementation, math

Memory and Casinos

data structures, math, probabilities

Vus the Cossack and a Field

divide and conquer, implementation, math

Multiset of Strings

bitmasks, brute force, dp, fft, flows, graphs, math, meet-in-the-middle, trees

A Shade of Moonlight

binary search, geometry, math, sortings, two pointers

Typewriter

brute force, math

Plane Tiling

geometry, implementation, math

Gifts from Grandfather Ahmed

dp, math, number theory

Write The Contest

binary search, dp, math

Half-decay tree

data structures, divide and conquer, dp, math, probabilities

Electrical Efficiency

combinatorics, data structures, dp, math, number theory, trees

Strange Radiation

binary search, implementation, math

Horse Races

dp, math

Igor and Interesting Numbers

brute force, combinatorics, dp, math

Sereja and Cinema

combinatorics, math

Savior

brute force, dsu, math

Digits

brute force, implementation, math

Packmen Strike Back

binary search, dp, math

Flags

dp, math, matrices

Not Quick Transformation

divide and conquer, math

Journey

dp, math

Little Elephant and Triangle

geometry, math

Deck-Building Game

divide and conquer, math

Olympic Games

math

King's Path

*special problem, math, trees

The Sum of the k-th Powers

math

Binary Table

bitmasks, brute force, divide and conquer, dp, fft, math

Integer Game

constructive algorithms, games, interactive, math

Cards

combinatorics, dp, math, number theory, probabilities

Quantifier Question

dfs and similar, dp, graphs, math

Deleting Numbers

interactive, math, number theory

Crypto Lights

combinatorics, dp, math, probabilities

Little Elephant and Broken Sorting

dp, math, probabilities

BFS Trees

combinatorics, dfs and similar, graphs, math, shortest paths, trees

You

dfs and similar, dp, math, number theory

Emotional Fishermen

combinatorics, dp, math, two pointers

Awesome Substrings

math, strings

Three Days Grace

data structures, dp, greedy, math, number theory, two pointers

XOR Counting

bitmasks, combinatorics, dp, math

Divide, XOR, and Conquer

bitmasks, dp, math

Stranger Trees

dp, math, matrices, trees

Xor-matic Number of the Graph

bitmasks, graphs, math, number theory, trees

Parametric MST

binary search, constructive algorithms, graphs, greedy, math, sortings

Twin Clusters

bitmasks, brute force, constructive algorithms, math, probabilities

Positions in Permutations

combinatorics, dp, math

Destroy the Colony

combinatorics, dp, math

Omkar and Akmar

chinese remainder theorem, combinatorics, constructive algorithms, fft, games, geometry, math, meet-in-the-middle, string suffix structures

Mercenaries

bitmasks, brute force, combinatorics, dp, dsu, math, two pointers

Sum the Fibonacci

bitmasks, divide and conquer, dp, fft, math

Enormous XOR

bitmasks, constructive algorithms, greedy, math, strings, two pointers

Song of the Sirens

combinatorics, divide and conquer, hashing, math, string suffix structures, strings