Solutions & Explanations

Browse 4,029+ detailed solutions with multiple approaches, code in Python, Java, C++ and more.

4,029 Solutions961 Easy2102 Medium966 Hard

Title	Difficulty	Acceptance	Topics	Solution
3234. Count the Number of Substrings With Dominant Ones	Medium	42.1%	Enumeration Sliding Window+1	Read
3237. Alt and Tab Simulation	Medium	54.3%	Array Hash Table+1	Read
3239. Minimum Number of Flips to Make Binary Grid Palindromic I	Medium	74.3%	Array Matrix+1	Read
3240. Minimum Number of Flips to Make Binary Grid Palindromic II	Medium	25.5%	Array Matrix+1	Read
3243. Shortest Distance After Road Addition Queries I	Medium	61.9%	Array Breadth-First Search+1	Read
3247. Number of Subsequences with Odd Sum	Medium	47.6%	Array Combinatorics+2	Read
3249. Count the Number of Good Nodes	Medium	55.0%	Depth-First Search Tree	Read
3252. Premier League Table Ranking II	Medium	58.5%	Database	Read
3253. Construct String with Minimum Cost (Easy)	Medium	58.8%		Read
3254. Find the Power of K-Size Subarrays I	Medium	62.1%	Array Sliding Window	Read
3255. Find the Power of K-Size Subarrays II	Medium	31.5%	Array Sliding Window	Read
3259. Maximum Energy Boost From Two Drinks	Medium	50.0%	Array Dynamic Programming	Read
3262. Find Overlapping Shifts	Medium	61.8%	Database	Read
3265. Count Almost Equal Pairs I	Medium	38.3%	Array Counting+3	Read
3271. Hash Divided String	Medium	83.3%	Simulation String	Read
3275. K-th Nearest Obstacle Queries	Medium	49.0%	Array Heap (Priority Queue)	Read
3278. Find Candidates for Data Scientist Position II	Medium	44.6%	Database	Read
3281. Maximize Score of Numbers in Ranges	Medium	35.6%	Array Binary Search+2	Read
3282. Reach End of Array With Max Score	Medium	33.5%	Array Greedy	Read
3284. Sum of Consecutive Subarrays	Medium	43.4%	Array Dynamic Programming+1	Read
3286. Find a Safe Walk Through a Grid	Medium	55.4%	Array Breadth-First Search+4	Read
3290. Maximum Multiplication Score	Medium	41.3%	Array Dynamic Programming	Read
3291. Minimum Number of Valid Strings to Form Target I	Medium	22.4%	Array Binary Search+7	Read
3293. Calculate Product Final Price	Medium	77.5%	Database	Read
3294. Convert Doubly Linked List to Array II	Medium	83.3%	Array Doubly-Linked List+1	Read
3295. Report Spam Message	Medium	48.6%	Array Hash Table+1	Read
3296. Minimum Number of Seconds to Make Mountain Height Zero	Medium	58.4%	Array Binary Search+3	Read
3297. Count Substrings That Can Be Rearranged to Contain a String I	Medium	42.9%	Hash Table Sliding Window+1	Read
3301. Maximize the Total Height of Unique Towers	Medium	37.3%	Array Greedy+1	Read
3302. Find the Lexicographically Smallest Valid Sequence	Medium	57.9%	Dynamic Programming Greedy+2	Read
3305. Count of Substrings Containing Every Vowel and K Consonants I	Medium	41.8%	Hash Table Sliding Window+1	Read
3306. Count of Substrings Containing Every Vowel and K Consonants II	Medium	40.6%	Hash Table Sliding Window+1	Read
3308. Find Top Performing Driver	Medium	53.6%	Database	Read
3309. Maximum Possible Number by Binary Concatenation	Medium	64.9%	Array Bit Manipulation+1	Read
3310. Remove Methods From Project	Medium	70.2%	Breadth-First Search Depth-First Search+1	Read
3315. Construct the Minimum Bitwise Array II	Medium	66.5%	Array Bit Manipulation	Read
3316. Find Maximum Removals From Source String	Medium	39.3%	Array Dynamic Programming+3	Read
3319. K-th Largest Perfect Subtree Size in Binary Tree	Medium	61.6%	Binary Tree Depth-First Search+2	Read
3322. Premier League Table Ranking III	Medium	73.1%	Database	Read
3323. Minimize Connected Groups by Inserting Interval	Medium	50.3%	Array Binary Search+2	Read
3324. Find the Sequence of Strings Appeared on the Screen	Medium	79.5%	Simulation String	Read
3325. Count Substrings With K-Frequency Characters I	Medium	56.3%	Hash Table Sliding Window+1	Read
3326. Minimum Division Operations to Make Array Non Decreasing	Medium	29.1%	Array Greedy+2	Read
3328. Find Cities in Each State II	Medium	70.6%	Database	Read
3331. Find Subtree Sizes After Changes	Medium	52.8%	Array Depth-First Search+3	Read
3332. Maximum Points Tourist Can Earn	Medium	47.3%	Array Dynamic Programming+1	Read
3334. Find the Maximum Factor Score of Array	Medium	41.0%	Array Math+1	Read
3335. Total Characters in String After Transformations I	Medium	45.7%	Counting Dynamic Programming+3	Read
3338. Second Highest Salary II	Medium	92.3%	Database	Read
3339. Find the Number of K-Even Arrays	Medium	61.3%	Dynamic Programming	Read

#3234Medium

Count the Number of Substrings With Dominant Ones

EnumerationSliding WindowString

Acceptance: 42.1%

#3237Medium

Alt and Tab Simulation

ArrayHash TableSimulation

Acceptance: 54.3%

#3239Medium

Minimum Number of Flips to Make Binary Grid Palindromic I

ArrayMatrixTwo Pointers

Acceptance: 74.3%

#3240Medium

Minimum Number of Flips to Make Binary Grid Palindromic II

ArrayMatrixTwo Pointers

Acceptance: 25.5%

#3243Medium

Shortest Distance After Road Addition Queries I

ArrayBreadth-First SearchGraph

Acceptance: 61.9%

#3247Medium

Number of Subsequences with Odd Sum

ArrayCombinatoricsDynamic Programming+1

Acceptance: 47.6%

#3249Medium

Count the Number of Good Nodes

Depth-First SearchTree

Acceptance: 55.0%

#3252Medium

Premier League Table Ranking II

Database

Acceptance: 58.5%

#3253Medium

Construct String with Minimum Cost (Easy)

Acceptance: 58.8%

#3254Medium

Find the Power of K-Size Subarrays I

ArraySliding Window

Acceptance: 62.1%

#3255Medium

Find the Power of K-Size Subarrays II

ArraySliding Window

Acceptance: 31.5%

#3259Medium

Maximum Energy Boost From Two Drinks

ArrayDynamic Programming

Acceptance: 50.0%

#3262Medium

Find Overlapping Shifts

Database

Acceptance: 61.8%

#3265Medium

Count Almost Equal Pairs I

ArrayCountingEnumeration+2

Acceptance: 38.3%

#3271Medium

Hash Divided String

SimulationString

Acceptance: 83.3%

#3275Medium

K-th Nearest Obstacle Queries

ArrayHeap (Priority Queue)

Acceptance: 49.0%

#3278Medium

Find Candidates for Data Scientist Position II

Database

Acceptance: 44.6%

#3281Medium

Maximize Score of Numbers in Ranges

ArrayBinary SearchGreedy+1

Acceptance: 35.6%

#3282Medium

Reach End of Array With Max Score

ArrayGreedy

Acceptance: 33.5%

#3284Medium

Sum of Consecutive Subarrays

ArrayDynamic ProgrammingTwo Pointers

Acceptance: 43.4%

#3286Medium

Find a Safe Walk Through a Grid

ArrayBreadth-First SearchGraph+3

Acceptance: 55.4%

#3290Medium

Maximum Multiplication Score

ArrayDynamic Programming

Acceptance: 41.3%

#3291Medium

Minimum Number of Valid Strings to Form Target I

ArrayBinary SearchDynamic Programming+6

Acceptance: 22.4%

#3293Medium

Calculate Product Final Price

Database

Acceptance: 77.5%

#3294Medium

Convert Doubly Linked List to Array II

ArrayDoubly-Linked ListLinked List

Acceptance: 83.3%

#3295Medium

Report Spam Message

ArrayHash TableString

Acceptance: 48.6%

#3296Medium

Minimum Number of Seconds to Make Mountain Height Zero

ArrayBinary SearchGreedy+2

Acceptance: 58.4%

#3297Medium

Count Substrings That Can Be Rearranged to Contain a String I

Hash TableSliding WindowString

Acceptance: 42.9%

#3301Medium

Maximize the Total Height of Unique Towers

ArrayGreedySorting

Acceptance: 37.3%

#3302Medium

Find the Lexicographically Smallest Valid Sequence

Dynamic ProgrammingGreedyString+1

Acceptance: 57.9%

#3305Medium

Count of Substrings Containing Every Vowel and K Consonants I

Hash TableSliding WindowString

Acceptance: 41.8%

#3306Medium

Count of Substrings Containing Every Vowel and K Consonants II

Hash TableSliding WindowString

Acceptance: 40.6%

#3308Medium

Find Top Performing Driver

Database

Acceptance: 53.6%

#3309Medium

Maximum Possible Number by Binary Concatenation

ArrayBit ManipulationEnumeration

Acceptance: 64.9%

#3310Medium

Remove Methods From Project

Breadth-First SearchDepth-First SearchGraph

Acceptance: 70.2%

#3315Medium

Construct the Minimum Bitwise Array II

ArrayBit Manipulation

Acceptance: 66.5%

#3316Medium

Find Maximum Removals From Source String

ArrayDynamic ProgrammingHash Table+2

Acceptance: 39.3%

#3319Medium

K-th Largest Perfect Subtree Size in Binary Tree

Binary TreeDepth-First SearchSorting+1

Acceptance: 61.6%

#3322Medium

Premier League Table Ranking III

Database

Acceptance: 73.1%

#3323Medium

Minimize Connected Groups by Inserting Interval

ArrayBinary SearchSliding Window+1

Acceptance: 50.3%

#3324Medium

Find the Sequence of Strings Appeared on the Screen

SimulationString

Acceptance: 79.5%

#3325Medium

Count Substrings With K-Frequency Characters I

Hash TableSliding WindowString

Acceptance: 56.3%

#3326Medium

Minimum Division Operations to Make Array Non Decreasing

ArrayGreedyMath+1

Acceptance: 29.1%

#3328Medium

Find Cities in Each State II

Database

Acceptance: 70.6%

#3331Medium

Find Subtree Sizes After Changes

ArrayDepth-First SearchHash Table+2

Acceptance: 52.8%

#3332Medium

Maximum Points Tourist Can Earn

ArrayDynamic ProgrammingMatrix

Acceptance: 47.3%

#3334Medium

Find the Maximum Factor Score of Array

ArrayMathNumber Theory

Acceptance: 41.0%

#3335Medium

Total Characters in String After Transformations I

CountingDynamic ProgrammingHash Table+2

Acceptance: 45.7%

#3338Medium

Second Highest Salary II

Database

Acceptance: 92.3%

#3339Medium

Find the Number of K-Even Arrays

Dynamic Programming

Acceptance: 61.3%

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Master DSA with Step-by-Step Solutions

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