Solutions & Explanations

Browse 4,030+ detailed solutions with multiple approaches, code in Python, Java, C++ and more.

4,030 Solutions961 Easy2102 Medium967 Hard

Title	Difficulty	Acceptance	Topics	Solution
3201. Find the Maximum Length of Valid Subsequence I	Medium	54.9%	Array Dynamic Programming	Read
3202. Find the Maximum Length of Valid Subsequence II	Medium	57.2%	Array Dynamic Programming	Read
3203. Find Minimum Diameter After Merging Two Trees	Hard	57.1%	Breadth-First Search Depth-First Search+2	Read
3204. Bitwise User Permissions Analysis	Medium	94.3%	Database	Read
3205. Maximum Array Hopping Score I	Medium	77.0%	Array Dynamic Programming+3	Read
3206. Alternating Groups I	Easy	69.5%	Array Sliding Window	Read
3207. Maximum Points After Enemy Battles	Medium	33.2%	Array Greedy	Read
3208. Alternating Groups II	Medium	59.9%	Array Sliding Window	Read
3209. Number of Subarrays With AND Value of K	Hard	35.7%	Array Binary Search+2	Read
3210. Find the Encrypted String	Easy	67.9%	String	Read
3211. Generate Binary Strings Without Adjacent Zeros	Medium	88.3%	Backtracking Bit Manipulation+1	Read
3212. Count Submatrices With Equal Frequency of X and Y	Medium	69.5%	Array Matrix+1	Read
3213. Construct String with Minimum Cost	Hard	19.0%	Array Dynamic Programming+2	Read
3214. Year on Year Growth Rate	Hard	51.7%	Database	Read
3215. Count Triplets with Even XOR Set Bits II	Medium	62.0%	Array Bit Manipulation	Read
3216. Lexicographically Smallest String After a Swap	Easy	54.6%	Greedy String	Read
3217. Delete Nodes From Linked List Present in Array	Medium	69.5%	Array Hash Table+1	Read
3218. Minimum Cost for Cutting Cake I	Medium	58.5%	Array Dynamic Programming+2	Read
3219. Minimum Cost for Cutting Cake II	Hard	54.2%	Array Greedy+1	Read
3220. Odd and Even Transactions	Medium	69.8%	Database	Read
3221. Maximum Array Hopping Score II	Medium	60.1%	Array Greedy+2	Read
3222. Find the Winning Player in Coin Game	Easy	53.9%	Game Theory Math+1	Read
3223. Minimum Length of String After Operations	Medium	75.0%	Counting Hash Table+1	Read
3224. Minimum Array Changes to Make Differences Equal	Medium	24.9%	Array Hash Table+1	Read
3225. Maximum Score From Grid Operations	Hard	63.5%	Array Dynamic Programming+2	Read
3226. Number of Bit Changes to Make Two Integers Equal	Easy	63.4%	Bit Manipulation	Read
3227. Vowels Game in a String	Medium	77.1%	Brainteaser Game Theory+2	Read
3228. Maximum Number of Operations to Move Ones to the End	Medium	67.2%	Counting Greedy+1	Read
3229. Minimum Operations to Make Array Equal to Target	Hard	41.4%	Array Dynamic Programming+3	Read
3230. Customer Purchasing Behavior Analysis	Medium	37.8%	Database	Read
3231. Minimum Number of Increasing Subsequence to Be Removed	Hard	47.9%	Array Binary Search	Read
3232. Find if Digit Game Can Be Won	Easy	81.5%	Array Math	Read
3233. Find the Count of Numbers Which Are Not Special	Medium	28.3%	Array Math+1	Read
3234. Count the Number of Substrings With Dominant Ones	Medium	42.1%	Enumeration Sliding Window+1	Read
3235. Check if the Rectangle Corner Is Reachable	Hard	24.4%	Array Breadth-First Search+4	Read
3236. CEO Subordinate Hierarchy	Hard	72.3%	Database	Read
3237. Alt and Tab Simulation	Medium	54.3%	Array Hash Table+1	Read
3238. Find the Number of Winning Players	Easy	60.5%	Array Counting+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
3241. Time Taken to Mark All Nodes	Hard	28.9%	Depth-First Search Dynamic Programming+2	Read
3242. Design Neighbor Sum Service	Easy	76.4%	Array Design+3	Read
3243. Shortest Distance After Road Addition Queries I	Medium	61.9%	Array Breadth-First Search+1	Read
3244. Shortest Distance After Road Addition Queries II	Hard	26.5%	Array Graph+2	Read
3245. Alternating Groups III	Hard	18.9%	Array Binary Indexed Tree	Read
3246. Premier League Table Ranking	Easy	83.3%	Database	Read
3247. Number of Subsequences with Odd Sum	Medium	47.6%	Array Combinatorics+2	Read
3248. Snake in Matrix	Easy	81.8%	Array Simulation+1	Read
3249. Count the Number of Good Nodes	Medium	55.0%	Depth-First Search Tree	Read
3250. Find the Count of Monotonic Pairs I	Hard	47.6%	Array Combinatorics+3	Read

#3201Medium

Find the Maximum Length of Valid Subsequence I

ArrayDynamic Programming

Acceptance: 54.9%

#3202Medium

Find the Maximum Length of Valid Subsequence II

ArrayDynamic Programming

Acceptance: 57.2%

#3203Hard

Find Minimum Diameter After Merging Two Trees

Breadth-First SearchDepth-First SearchGraph+1

Acceptance: 57.1%

#3204Medium

Bitwise User Permissions Analysis

Database

Acceptance: 94.3%

#3205Medium

Maximum Array Hopping Score I

ArrayDynamic ProgrammingGreedy+2

Acceptance: 77.0%

#3206Easy

Alternating Groups I

ArraySliding Window

Acceptance: 69.5%

#3207Medium

Maximum Points After Enemy Battles

ArrayGreedy

Acceptance: 33.2%

#3208Medium

Alternating Groups II

ArraySliding Window

Acceptance: 59.9%

#3209Hard

Number of Subarrays With AND Value of K

ArrayBinary SearchBit Manipulation+1

Acceptance: 35.7%

#3210Easy

Find the Encrypted String

String

Acceptance: 67.9%

#3211Medium

Generate Binary Strings Without Adjacent Zeros

BacktrackingBit ManipulationString

Acceptance: 88.3%

#3212Medium

Count Submatrices With Equal Frequency of X and Y

ArrayMatrixPrefix Sum

Acceptance: 69.5%

#3213Hard

Construct String with Minimum Cost

ArrayDynamic ProgrammingString+1

Acceptance: 19.0%

#3214Hard

Year on Year Growth Rate

Database

Acceptance: 51.7%

#3215Medium

Count Triplets with Even XOR Set Bits II

ArrayBit Manipulation

Acceptance: 62.0%

#3216Easy

Lexicographically Smallest String After a Swap

GreedyString

Acceptance: 54.6%

#3217Medium

Delete Nodes From Linked List Present in Array

ArrayHash TableLinked List

Acceptance: 69.5%

#3218Medium

Minimum Cost for Cutting Cake I

ArrayDynamic ProgrammingGreedy+1

Acceptance: 58.5%

#3219Hard

Minimum Cost for Cutting Cake II

ArrayGreedySorting

Acceptance: 54.2%

#3220Medium

Odd and Even Transactions

Database

Acceptance: 69.8%

#3221Medium

Maximum Array Hopping Score II

ArrayGreedyMonotonic Stack+1

Acceptance: 60.1%

#3222Easy

Find the Winning Player in Coin Game

Game TheoryMathSimulation

Acceptance: 53.9%

#3223Medium

Minimum Length of String After Operations

CountingHash TableString

Acceptance: 75.0%

#3224Medium

Minimum Array Changes to Make Differences Equal

ArrayHash TablePrefix Sum

Acceptance: 24.9%

#3225Hard

Maximum Score From Grid Operations

ArrayDynamic ProgrammingMatrix+1

Acceptance: 63.5%

#3226Easy

Number of Bit Changes to Make Two Integers Equal

Bit Manipulation

Acceptance: 63.4%

#3227Medium

Vowels Game in a String

BrainteaserGame TheoryMath+1

Acceptance: 77.1%

#3228Medium

Maximum Number of Operations to Move Ones to the End

CountingGreedyString

Acceptance: 67.2%

#3229Hard

Minimum Operations to Make Array Equal to Target

ArrayDynamic ProgrammingGreedy+2

Acceptance: 41.4%

#3230Medium

Customer Purchasing Behavior Analysis

Database

Acceptance: 37.8%

#3231Hard

Minimum Number of Increasing Subsequence to Be Removed

ArrayBinary Search

Acceptance: 47.9%

#3232Easy

Find if Digit Game Can Be Won

ArrayMath

Acceptance: 81.5%

#3233Medium

Find the Count of Numbers Which Are Not Special

ArrayMathNumber Theory

Acceptance: 28.3%

#3234Medium

Count the Number of Substrings With Dominant Ones

EnumerationSliding WindowString

Acceptance: 42.1%

#3235Hard

Check if the Rectangle Corner Is Reachable

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 24.4%

#3236Hard

CEO Subordinate Hierarchy

Database

Acceptance: 72.3%

#3237Medium

Alt and Tab Simulation

ArrayHash TableSimulation

Acceptance: 54.3%

#3238Easy

Find the Number of Winning Players

ArrayCountingHash Table

Acceptance: 60.5%

#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%

#3241Hard

Time Taken to Mark All Nodes

Depth-First SearchDynamic ProgrammingGraph+1

Acceptance: 28.9%

#3242Easy

Design Neighbor Sum Service

ArrayDesignHash Table+2

Acceptance: 76.4%

#3243Medium

Shortest Distance After Road Addition Queries I

ArrayBreadth-First SearchGraph

Acceptance: 61.9%

#3244Hard

Shortest Distance After Road Addition Queries II

ArrayGraphGreedy+1

Acceptance: 26.5%

#3245Hard

Alternating Groups III

ArrayBinary Indexed Tree

Acceptance: 18.9%

#3246Easy

Premier League Table Ranking

Database

Acceptance: 83.3%

#3247Medium

Number of Subsequences with Odd Sum

ArrayCombinatoricsDynamic Programming+1

Acceptance: 47.6%

#3248Easy

Snake in Matrix

ArraySimulationString

Acceptance: 81.8%

#3249Medium

Count the Number of Good Nodes

Depth-First SearchTree

Acceptance: 55.0%

#3250Hard

Find the Count of Monotonic Pairs I

ArrayCombinatoricsDynamic Programming+2

Acceptance: 47.6%

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