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
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
3303. Find the Occurrence of First Almost Equal Substring	Hard	16.0%	String String Matching	Read
3304. Find the K-th Character in String Game I	Easy	81.6%	Bit Manipulation Math+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
3307. Find the K-th Character in String Game II	Hard	48.5%	Bit Manipulation Math+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
3311. Construct 2D Grid Matching Graph Layout	Hard	29.3%	Array Graph+2	Read
3312. Sorted GCD Pair Queries	Hard	58.4%	Array Binary Search+6	Read
3313. Find the Last Marked Nodes in Tree	Hard	57.1%	Depth-First Search Tree	Read
3314. Construct the Minimum Bitwise Array I	Easy	85.3%	Array Bit Manipulation	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
3317. Find the Number of Possible Ways for an Event	Hard	34.8%	Combinatorics Dynamic Programming+1	Read
3318. Find X-Sum of All K-Long Subarrays I	Easy	76.1%	Array Hash Table+2	Read
3319. K-th Largest Perfect Subtree Size in Binary Tree	Medium	61.6%	Binary Tree Depth-First Search+2	Read
3320. Count The Number of Winning Sequences	Hard	32.4%	Dynamic Programming String	Read
3321. Find X-Sum of All K-Long Subarrays II	Hard	41.1%	Array Hash Table+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
3327. Check if DFS Strings Are Palindromes	Hard	20.9%	Array Depth-First Search+4	Read
3328. Find Cities in Each State II	Medium	70.6%	Database	Read
3329. Count Substrings With K-Frequency Characters II	Hard	72.2%	Hash Table Sliding Window+1	Read
3330. Find the Original Typed String I	Easy	72.1%	String	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
3333. Find the Original Typed String II	Hard	45.6%	Dynamic Programming Prefix Sum+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
3336. Find the Number of Subsequences With Equal GCD	Hard	66.7%	Array Dynamic Programming+2	Read
3337. Total Characters in String After Transformations II	Hard	58.0%	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
3340. Check Balanced String	Easy	82.9%	String	Read
3341. Find Minimum Time to Reach Last Room I	Medium	55.5%	Array Graph+3	Read
3342. Find Minimum Time to Reach Last Room II	Medium	67.3%	Array Graph+3	Read
3343. Count Number of Balanced Permutations	Hard	49.1%	Combinatorics Dynamic Programming+2	Read
3344. Maximum Sized Array	Medium	51.4%	Binary Search Bit Manipulation	Read
3345. Smallest Divisible Digit Product I	Easy	73.1%	Enumeration Math	Read
3346. Maximum Frequency of an Element After Performing Operations I	Medium	40.1%	Array Binary Search+3	Read
3347. Maximum Frequency of an Element After Performing Operations II	Hard	53.8%	Array Binary Search+3	Read
3348. Smallest Divisible Digit Product II	Hard	45.3%	Backtracking Greedy+3	Read
3349. Adjacent Increasing Subarrays Detection I	Easy	48.0%	Array	Read
3350. Adjacent Increasing Subarrays Detection II	Medium	58.9%	Array Binary Search	Read

#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%

#3303Hard

Find the Occurrence of First Almost Equal Substring

StringString Matching

Acceptance: 16.0%

#3304Easy

Find the K-th Character in String Game I

Bit ManipulationMathRecursion+1

Acceptance: 81.6%

#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%

#3307Hard

Find the K-th Character in String Game II

Bit ManipulationMathRecursion

Acceptance: 48.5%

#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%

#3311Hard

Construct 2D Grid Matching Graph Layout

ArrayGraphHash Table+1

Acceptance: 29.3%

#3312Hard

Sorted GCD Pair Queries

ArrayBinary SearchCombinatorics+5

Acceptance: 58.4%

#3313Hard

Find the Last Marked Nodes in Tree

Depth-First SearchTree

Acceptance: 57.1%

#3314Easy

Construct the Minimum Bitwise Array I

ArrayBit Manipulation

Acceptance: 85.3%

#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%

#3317Hard

Find the Number of Possible Ways for an Event

CombinatoricsDynamic ProgrammingMath

Acceptance: 34.8%

#3318Easy

Find X-Sum of All K-Long Subarrays I

ArrayHash TableHeap (Priority Queue)+1

Acceptance: 76.1%

#3319Medium

K-th Largest Perfect Subtree Size in Binary Tree

Binary TreeDepth-First SearchSorting+1

Acceptance: 61.6%

#3320Hard

Count The Number of Winning Sequences

Dynamic ProgrammingString

Acceptance: 32.4%

#3321Hard

Find X-Sum of All K-Long Subarrays II

ArrayHash TableHeap (Priority Queue)+1

Acceptance: 41.1%

#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%

#3327Hard

Check if DFS Strings Are Palindromes

ArrayDepth-First SearchHash Function+3

Acceptance: 20.9%

#3328Medium

Find Cities in Each State II

Database

Acceptance: 70.6%

#3329Hard

Count Substrings With K-Frequency Characters II

Hash TableSliding WindowString

Acceptance: 72.2%

#3330Easy

Find the Original Typed String I

String

Acceptance: 72.1%

#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%

#3333Hard

Find the Original Typed String II

Dynamic ProgrammingPrefix SumString

Acceptance: 45.6%

#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%

#3336Hard

Find the Number of Subsequences With Equal GCD

ArrayDynamic ProgrammingMath+1

Acceptance: 66.7%

#3337Hard

Total Characters in String After Transformations II

CountingDynamic ProgrammingHash Table+2

Acceptance: 58.0%

#3338Medium

Second Highest Salary II

Database

Acceptance: 92.3%

#3339Medium

Find the Number of K-Even Arrays

Dynamic Programming

Acceptance: 61.3%

#3340Easy

Check Balanced String

String

Acceptance: 82.9%

#3341Medium

Find Minimum Time to Reach Last Room I

ArrayGraphHeap (Priority Queue)+2

Acceptance: 55.5%

#3342Medium

Find Minimum Time to Reach Last Room II

ArrayGraphHeap (Priority Queue)+2

Acceptance: 67.3%

#3343Hard

Count Number of Balanced Permutations

CombinatoricsDynamic ProgrammingMath+1

Acceptance: 49.1%

#3344Medium

Maximum Sized Array

Binary SearchBit Manipulation

Acceptance: 51.4%

#3345Easy

Smallest Divisible Digit Product I

EnumerationMath

Acceptance: 73.1%

#3346Medium

Maximum Frequency of an Element After Performing Operations I

ArrayBinary SearchPrefix Sum+2

Acceptance: 40.1%

#3347Hard

Maximum Frequency of an Element After Performing Operations II

ArrayBinary SearchPrefix Sum+2

Acceptance: 53.8%

#3348Hard

Smallest Divisible Digit Product II

BacktrackingGreedyMath+2

Acceptance: 45.3%

#3349Easy

Adjacent Increasing Subarrays Detection I

Array

Acceptance: 48.0%

#3350Medium

Adjacent Increasing Subarrays Detection II

ArrayBinary Search

Acceptance: 58.9%

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Master DSA with Step-by-Step Solutions

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How to Use These Solutions

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