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
3251. Find the Count of Monotonic Pairs II	Hard	24.7%	Array Combinatorics+3	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
3256. Maximum Value Sum by Placing Three Rooks I	Hard	17.0%	Array Dynamic Programming+2	Read
3257. Maximum Value Sum by Placing Three Rooks II	Hard	26.1%	Array Dynamic Programming+2	Read
3258. Count Substrings That Satisfy K-Constraint I	Easy	78.9%	Sliding Window String	Read
3259. Maximum Energy Boost From Two Drinks	Medium	50.0%	Array Dynamic Programming	Read
3260. Find the Largest Palindrome Divisible by K	Hard	17.0%	Dynamic Programming Greedy+3	Read
3261. Count Substrings That Satisfy K-Constraint II	Hard	23.5%	Array Binary Search+3	Read
3262. Find Overlapping Shifts	Medium	61.8%	Database	Read
3263. Convert Doubly Linked List to Array I	Easy	95.0%	Array Doubly-Linked List+1	Read
3264. Final Array State After K Multiplication Operations I	Easy	86.9%	Array Heap (Priority Queue)+2	Read
3265. Count Almost Equal Pairs I	Medium	38.3%	Array Counting+3	Read
3266. Final Array State After K Multiplication Operations II	Hard	13.7%	Array Heap (Priority Queue)+1	Read
3267. Count Almost Equal Pairs II	Hard	27.7%	Array Counting+3	Read
3268. Find Overlapping Shifts II	Hard	70.0%	Database	Read
3269. Constructing Two Increasing Arrays	Hard	61.8%	Array Dynamic Programming	Read
3270. Find the Key of the Numbers	Easy	76.1%	Math	Read
3271. Hash Divided String	Medium	83.3%	Simulation String	Read
3272. Find the Count of Good Integers	Hard	69.5%	Combinatorics Enumeration+2	Read
3273. Minimum Amount of Damage Dealt to Bob	Hard	39.6%	Array Greedy+1	Read
3274. Check if Two Chessboard Squares Have the Same Color	Easy	72.3%	Math String	Read
3275. K-th Nearest Obstacle Queries	Medium	49.0%	Array Heap (Priority Queue)	Read
3276. Select Cells in Grid With Maximum Score	Hard	15.7%	Array Bit Manipulation+3	Read
3277. Maximum XOR Score Subarray Queries	Hard	42.8%	Array Dynamic Programming	Read
3278. Find Candidates for Data Scientist Position II	Medium	44.6%	Database	Read
3279. Maximum Total Area Occupied by Pistons	Hard	41.3%	Array Counting+4	Read
3280. Convert Date to Binary	Easy	88.8%	Math String	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
3283. Maximum Number of Moves to Kill All Pawns	Hard	33.7%	Array Bit Manipulation+4	Read
3284. Sum of Consecutive Subarrays	Medium	43.4%	Array Dynamic Programming+1	Read
3285. Find Indices of Stable Mountains	Easy	86.5%	Array	Read
3286. Find a Safe Walk Through a Grid	Medium	55.4%	Array Breadth-First Search+4	Read
3287. Find the Maximum Sequence Value of Array	Hard	21.9%	Array Bit Manipulation+1	Read
3288. Length of the Longest Increasing Path	Hard	19.9%	Array Binary Search+1	Read
3289. The Two Sneaky Numbers of Digitville	Easy	89.9%	Array Hash Table+1	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
3292. Minimum Number of Valid Strings to Form Target II	Hard	21.1%	Array Binary Search+6	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
3298. Count Substrings That Can Be Rearranged to Contain a String II	Hard	55.2%	Hash Table Sliding Window+1	Read
3299. Sum of Consecutive Subsequences	Hard	44.9%	Array Dynamic Programming+1	Read
3300. Minimum Element After Replacement With Digit Sum	Easy	89.6%	Array Math	Read

#3251Hard

Find the Count of Monotonic Pairs II

ArrayCombinatoricsDynamic Programming+2

Acceptance: 24.7%

#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%

#3256Hard

Maximum Value Sum by Placing Three Rooks I

ArrayDynamic ProgrammingEnumeration+1

Acceptance: 17.0%

#3257Hard

Maximum Value Sum by Placing Three Rooks II

ArrayDynamic ProgrammingEnumeration+1

Acceptance: 26.1%

#3258Easy

Count Substrings That Satisfy K-Constraint I

Sliding WindowString

Acceptance: 78.9%

#3259Medium

Maximum Energy Boost From Two Drinks

ArrayDynamic Programming

Acceptance: 50.0%

#3260Hard

Find the Largest Palindrome Divisible by K

Dynamic ProgrammingGreedyMath+2

Acceptance: 17.0%

#3261Hard

Count Substrings That Satisfy K-Constraint II

ArrayBinary SearchPrefix Sum+2

Acceptance: 23.5%

#3262Medium

Find Overlapping Shifts

Database

Acceptance: 61.8%

#3263Easy

Convert Doubly Linked List to Array I

ArrayDoubly-Linked ListLinked List

Acceptance: 95.0%

#3264Easy

Final Array State After K Multiplication Operations I

ArrayHeap (Priority Queue)Math+1

Acceptance: 86.9%

#3265Medium

Count Almost Equal Pairs I

ArrayCountingEnumeration+2

Acceptance: 38.3%

#3266Hard

Final Array State After K Multiplication Operations II

ArrayHeap (Priority Queue)Simulation

Acceptance: 13.7%

#3267Hard

Count Almost Equal Pairs II

ArrayCountingEnumeration+2

Acceptance: 27.7%

#3268Hard

Find Overlapping Shifts II

Database

Acceptance: 70.0%

#3269Hard

Constructing Two Increasing Arrays

ArrayDynamic Programming

Acceptance: 61.8%

#3270Easy

Find the Key of the Numbers

Math

Acceptance: 76.1%

#3271Medium

Hash Divided String

SimulationString

Acceptance: 83.3%

#3272Hard

Find the Count of Good Integers

CombinatoricsEnumerationHash Table+1

Acceptance: 69.5%

#3273Hard

Minimum Amount of Damage Dealt to Bob

ArrayGreedySorting

Acceptance: 39.6%

#3274Easy

Check if Two Chessboard Squares Have the Same Color

MathString

Acceptance: 72.3%

#3275Medium

K-th Nearest Obstacle Queries

ArrayHeap (Priority Queue)

Acceptance: 49.0%

#3276Hard

Select Cells in Grid With Maximum Score

ArrayBit ManipulationBitmask+2

Acceptance: 15.7%

#3277Hard

Maximum XOR Score Subarray Queries

ArrayDynamic Programming

Acceptance: 42.8%

#3278Medium

Find Candidates for Data Scientist Position II

Database

Acceptance: 44.6%

#3279Hard

Maximum Total Area Occupied by Pistons

ArrayCountingHash Table+3

Acceptance: 41.3%

#3280Easy

Convert Date to Binary

MathString

Acceptance: 88.8%

#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%

#3283Hard

Maximum Number of Moves to Kill All Pawns

ArrayBit ManipulationBitmask+3

Acceptance: 33.7%

#3284Medium

Sum of Consecutive Subarrays

ArrayDynamic ProgrammingTwo Pointers

Acceptance: 43.4%

#3285Easy

Find Indices of Stable Mountains

Array

Acceptance: 86.5%

#3286Medium

Find a Safe Walk Through a Grid

ArrayBreadth-First SearchGraph+3

Acceptance: 55.4%

#3287Hard

Find the Maximum Sequence Value of Array

ArrayBit ManipulationDynamic Programming

Acceptance: 21.9%

#3288Hard

Length of the Longest Increasing Path

ArrayBinary SearchSorting

Acceptance: 19.9%

#3289Easy

The Two Sneaky Numbers of Digitville

ArrayHash TableMath

Acceptance: 89.9%

#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%

#3292Hard

Minimum Number of Valid Strings to Form Target II

ArrayBinary SearchDynamic Programming+5

Acceptance: 21.1%

#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%

#3298Hard

Count Substrings That Can Be Rearranged to Contain a String II

Hash TableSliding WindowString

Acceptance: 55.2%

#3299Hard

Sum of Consecutive Subsequences

ArrayDynamic ProgrammingHash Table

Acceptance: 44.9%

#3300Easy

Minimum Element After Replacement With Digit Sum

ArrayMath

Acceptance: 89.6%

1 2 365 66 6779 80 81

Page 66 of 81

Master DSA with Step-by-Step Solutions

Each solution article on FleetCode breaks down the problem into multiple approaches, from brute force to optimal, with detailed explanations and code in Python, Java, C++ and more. Understanding why an approach works - not just copying code - is what separates candidates who clear interviews from those who don't.

How to Use These Solutions

Try the problem first: Spend at least 20 minutes before reading the solution
Read all approaches: Start from brute force to understand the problem fully, then study the optimized solution
Understand the complexity: Pay attention to time and space analysis for each approach
Code it yourself: After understanding the approach, close the solution and implement from memory
Revisit after a week: Spaced repetition helps retain problem-solving patterns