Sum of Substrings

brute force, constructive algorithms, greedy, math, strings

Shifting String

graphs, math, number theory, strings

Price Maximization

binary search, greedy, math, two pointers

Infected Tree

dfs and similar, dp, trees

Manipulating History

constructive algorithms, greedy, strings

Railway System

constructive algorithms, graphs, greedy, interactive, sortings

The Enchanted Forest

brute force, greedy

Traps

constructive algorithms, greedy, sortings

Column Swapping

brute force, constructive algorithms, greedy, implementation, sortings

LIS or Reverse LIS?

constructive algorithms, greedy, implementation, math

Required Length

brute force, dfs and similar, dp, hashing, shortest paths

Binary String

binary search, greedy, strings, two pointers

Rooks Defenders

data structures, implementation

Tokitsukaze and Good 01-String (hard version)

dp, greedy, implementation

Tokitsukaze and Meeting

data structures, implementation, math

Tokitsukaze and Strange Inequality

brute force, data structures, dp

Maximum Crossings (Hard Version)

data structures, divide and conquer, sortings

Maximum Crossings (Easy Version)

brute force

Vlad and Unfinished Business

dfs and similar, dp, greedy, trees

Replace With the Previous, Minimize

dsu, greedy, strings

Desktop Rearrangement

data structures, greedy, implementation

Palindrome Basis

brute force, dp, math, number theory

Cyclic Rotation

constructive algorithms, greedy, implementation, two pointers

Insert a Progression

brute force, constructive algorithms, greedy

Very Suspicious

binary search, brute force, geometry, greedy, implementation, math

Where is the Pizza?

data structures, dfs and similar, dsu, graphs, implementation, math

Labyrinth

dfs and similar, graphs

Connect the Points

brute force, constructive algorithms, geometry

Tree Infection

binary search, greedy, sortings, trees

Water the Trees

binary search, greedy, math

Promising String (easy version)

brute force, implementation, math, strings

Matrix and Shifts

brute force, constructive algorithms, greedy, implementation

Maximum Product Strikes Back

brute force, implementation, math, two pointers

Line Empire

binary search, brute force, dp, greedy, implementation, math

388535 (Easy Version)

bitmasks, math

Shinju and the Lost Permutation

constructive algorithms, math

Alice and the Cake

data structures, greedy, implementation, sortings

Fault-tolerant Network

brute force, data structures, implementation

Integral Array

brute force, constructive algorithms, data structures, math

Weird Sum

combinatorics, data structures, geometry, math, matrices, sortings

Factorials and Powers of Two

bitmasks, brute force, constructive algorithms, dp, math

Cross Coloring

data structures, implementation, math

Increase Subarray Sums

brute force, dp, greedy, implementation

Yet Another Minimization Problem

dp, greedy, math

Infinite Set

bitmasks, dp, math, matrices, number theory, strings

Fortune Telling

bitmasks, math

Make Them Equal

dp, greedy

Strange Test

binary search, bitmasks, brute force, dp, math

Range and Partition

binary search, constructive algorithms, data structures, greedy, two pointers

And Matching

bitmasks, constructive algorithms

Peculiar Movie Preferences

greedy, strings

Meximum Array

binary search, constructive algorithms, greedy, implementation, math, two pointers

Not Assigning

constructive algorithms, dfs and similar, number theory, trees

Monsters And Spells

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

Road Optimization

dp

Palindromes Coloring

binary search, greedy, sortings, strings

Balanced Stone Heaps

binary search, greedy

Set or Decrease

binary search, brute force, greedy, sortings

Hidden Permutations

dfs and similar, interactive, math

Integers Shop

data structures, greedy, implementation

BA-String

brute force, dp, greedy, implementation, math

MEX and Increments

constructive algorithms, data structures, dp, greedy, implementation, math, sortings

New Year's Problem

binary search, greedy, sortings

Singers' Tour

constructive algorithms, math

Too Many Impostors (easy version)

constructive algorithms, implementation, interactive

Representative Edges

brute force, geometry, implementation, math

Menorah

brute force, graphs, greedy, math

Divan and bitwise operations

bitmasks, combinatorics, constructive algorithms, dp, math

X-Magic Pair

math, number theory

ATM and Students

binary search, data structures, two pointers

Escape The Maze (easy version)

dfs and similar, greedy, shortest paths, trees, two pointers

Weights Assignment For Tree Edges

constructive algorithms, trees

Keshi Is Throwing a Party

binary search, greedy

Social Network

dsu, graphs, greedy, implementation, trees

Complex Market Analysis

binary search, dp, implementation, number theory, schedules, two pointers

Game Master

data structures, dfs and similar, dp, graphs, greedy, two pointers

Robot on the Board 1

implementation

Banknotes

greedy, number theory

Dominant Character

brute force, greedy, implementation, strings

Moderate Modular Mode

constructive algorithms, math, number theory

Robot Factory

bitmasks, dfs and similar

Training Session

combinatorics, data structures, geometry, implementation, math

The Number of Imposters

constructive algorithms, dfs and similar, dp, dsu, graphs

Gardener and Tree

brute force, data structures, dfs and similar, greedy, implementation, trees

Bakry and Partitioning

bitmasks, constructive algorithms, dfs and similar, dp, graphs, trees

Omkar and the Meaning of Life

constructive algorithms, greedy, interactive

Omkar and Determination

data structures, dp

Korney Korneevich and XOR (easy version)

bitmasks, dp, greedy

Vupsen, Pupsen and 0

constructive algorithms, math

Portal

brute force, data structures, dp, greedy, implementation

Array Stabilization (AND version)

brute force, graphs, math, number theory, shortest paths

Array Optimization by Deque

data structures, greedy

Productive Meeting

constructive algorithms, graphs, greedy

Ticks

greedy, implementation

Higher Order Functions

implementation, strings

Jeopardy of Dropped Balls

binary search, brute force, dsu, implementation

Divisible by Twenty-Five

brute force, dfs and similar, dp

Swaps

greedy, math, sortings

Book

binary search, brute force, data structures, dp, graphs, implementation, sortings

Fix the String

*special problem, bitmasks, dp, greedy