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
2340. Minimum Adjacent Swaps to Make a Valid Array	Medium	72.6%	Array Greedy	Read
2342. Max Sum of a Pair With Equal Sum of Digits	Medium	66.0%	Array Hash Table+2	Read
2343. Query Kth Smallest Trimmed Number	Medium	47.9%	Array Divide and Conquer+5	Read
2345. Finding the Number of Visible Mountains	Medium	37.3%	Array Monotonic Stack+2	Read
2346. Compute the Rank as a Percentage	Medium	33.7%	Database	Read
2348. Number of Zero-Filled Subarrays	Medium	70.1%	Array Math	Read
2349. Design a Number Container System	Medium	57.1%	Design Hash Table+2	Read
2352. Equal Row and Column Pairs	Medium	70.9%	Array Hash Table+2	Read
2353. Design a Food Rating System	Medium	52.9%	Design Hash Table+2	Read
2358. Maximum Number of Groups Entering a Competition	Medium	68.5%	Array Binary Search+2	Read
2359. Find Closest Node to Given Two Nodes	Medium	53.0%	Depth-First Search Graph	Read
2364. Count Number of Bad Pairs	Medium	54.2%	Array Counting+2	Read
2365. Task Scheduler II	Medium	54.7%	Array Hash Table+1	Read
2368. Reachable Nodes With Restrictions	Medium	60.8%	Array Breadth-First Search+5	Read
2369. Check if There is a Valid Partition For The Array	Medium	52.5%	Array Dynamic Programming	Read
2370. Longest Ideal Subsequence	Medium	47.1%	Dynamic Programming Hash Table+1	Read
2372. Calculate the Influence of Each Salesperson	Medium	83.2%	Database	Read
2374. Node With Highest Edge Score	Medium	49.3%	Graph Hash Table	Read
2375. Construct Smallest Number From DI String	Medium	85.6%	Backtracking Greedy+2	Read
2378. Choose Edges to Maximize Score in a Tree	Medium	56.5%	Depth-First Search Dynamic Programming+1	Read
2380. Time Needed to Rearrange a Binary String	Medium	53.3%	Dynamic Programming Simulation+1	Read
2381. Shifting Letters II	Medium	53.6%	Array Prefix Sum+1	Read
2384. Largest Palindromic Number	Medium	37.1%	Counting Greedy+2	Read
2385. Amount of Time for Binary Tree to Be Infected	Medium	65.8%	Binary Tree Breadth-First Search+3	Read
2387. Median of a Row Wise Sorted Matrix	Medium	70.9%	Array Binary Search+1	Read
2388. Change Null Values in a Table to the Previous Value	Medium	51.0%	Database	Read
2390. Removing Stars From a String	Medium	79.7%	Simulation Stack+1	Read
2391. Minimum Amount of Time to Collect Garbage	Medium	85.2%	Array Prefix Sum+1	Read
2393. Count Strictly Increasing Subarrays	Medium	70.8%	Array Dynamic Programming+1	Read
2394. Employees With Deductions	Medium	41.0%	Database	Read
2396. Strictly Palindromic Number	Medium	90.3%	Brainteaser Math+1	Read
2397. Maximum Rows Covered by Columns	Medium	58.4%	Array Backtracking+3	Read
2400. Number of Ways to Reach a Position After Exactly k Steps	Medium	37.4%	Combinatorics Dynamic Programming+1	Read
2401. Longest Nice Subarray	Medium	64.8%	Array Bit Manipulation+1	Read
2405. Optimal Partition of String	Medium	78.0%	Greedy Hash Table+1	Read
2406. Divide Intervals Into Minimum Number of Groups	Medium	63.7%	Array Greedy+4	Read
2408. Design SQL	Medium	63.9%	Array Design+2	Read
2410. Maximum Matching of Players With Trainers	Medium	75.2%	Array Greedy+2	Read
2411. Smallest Subarrays With Maximum Bitwise OR	Medium	62.0%	Array Binary Search+2	Read
2414. Length of the Longest Alphabetical Continuous Substring	Medium	61.0%	String	Read
2415. Reverse Odd Levels of Binary Tree	Medium	86.7%	Binary Tree Breadth-First Search+2	Read
2417. Closest Fair Integer	Medium	43.7%	Enumeration Math	Read
2419. Longest Subarray With Maximum Bitwise AND	Medium	65.4%	Array Bit Manipulation+1	Read
2420. Find All Good Indices	Medium	40.8%	Array Dynamic Programming+1	Read
2422. Merge Operations to Turn Array Into a Palindrome	Medium	69.0%	Array Greedy+1	Read
2424. Longest Uploaded Prefix	Medium	55.5%	Binary Indexed Tree Binary Search+5	Read
2425. Bitwise XOR of All Pairings	Medium	66.9%	Array Bit Manipulation+1	Read
2428. Maximum Sum of an Hourglass	Medium	77.1%	Array Matrix+1	Read
2429. Minimize XOR	Medium	62.4%	Bit Manipulation Greedy	Read
2431. Maximize Total Tastiness of Purchased Fruits	Medium	64.6%	Array Dynamic Programming	Read

#2340Medium

Minimum Adjacent Swaps to Make a Valid Array

ArrayGreedy

Acceptance: 72.6%

#2342Medium

Max Sum of a Pair With Equal Sum of Digits

ArrayHash TableHeap (Priority Queue)+1

Acceptance: 66.0%

#2343Medium

Query Kth Smallest Trimmed Number

ArrayDivide and ConquerHeap (Priority Queue)+4

Acceptance: 47.9%

#2345Medium

Finding the Number of Visible Mountains

ArrayMonotonic StackSorting+1

Acceptance: 37.3%

#2346Medium

Compute the Rank as a Percentage

Database

Acceptance: 33.7%

#2348Medium

Number of Zero-Filled Subarrays

ArrayMath

Acceptance: 70.1%

#2349Medium

Design a Number Container System

DesignHash TableHeap (Priority Queue)+1

Acceptance: 57.1%

#2352Medium

Equal Row and Column Pairs

ArrayHash TableMatrix+1

Acceptance: 70.9%

#2353Medium

Design a Food Rating System

DesignHash TableHeap (Priority Queue)+1

Acceptance: 52.9%

#2358Medium

Maximum Number of Groups Entering a Competition

ArrayBinary SearchGreedy+1

Acceptance: 68.5%

#2359Medium

Find Closest Node to Given Two Nodes

Depth-First SearchGraph

Acceptance: 53.0%

#2364Medium

Count Number of Bad Pairs

ArrayCountingHash Table+1

Acceptance: 54.2%

#2365Medium

Task Scheduler II

ArrayHash TableSimulation

Acceptance: 54.7%

#2368Medium

Reachable Nodes With Restrictions

ArrayBreadth-First SearchDepth-First Search+4

Acceptance: 60.8%

#2369Medium

Check if There is a Valid Partition For The Array

ArrayDynamic Programming

Acceptance: 52.5%

#2370Medium

Longest Ideal Subsequence

Dynamic ProgrammingHash TableString

Acceptance: 47.1%

#2372Medium

Calculate the Influence of Each Salesperson

Database

Acceptance: 83.2%

#2374Medium

Node With Highest Edge Score

GraphHash Table

Acceptance: 49.3%

#2375Medium

Construct Smallest Number From DI String

BacktrackingGreedyStack+1

Acceptance: 85.6%

#2378Medium

Choose Edges to Maximize Score in a Tree

Depth-First SearchDynamic ProgrammingTree

Acceptance: 56.5%

#2380Medium

Time Needed to Rearrange a Binary String

Dynamic ProgrammingSimulationString

Acceptance: 53.3%

#2381Medium

Shifting Letters II

ArrayPrefix SumString

Acceptance: 53.6%

#2384Medium

Largest Palindromic Number

CountingGreedyHash Table+1

Acceptance: 37.1%

#2385Medium

Amount of Time for Binary Tree to Be Infected

Binary TreeBreadth-First SearchDepth-First Search+2

Acceptance: 65.8%

#2387Medium

Median of a Row Wise Sorted Matrix

ArrayBinary SearchMatrix

Acceptance: 70.9%

#2388Medium

Change Null Values in a Table to the Previous Value

Database

Acceptance: 51.0%

#2390Medium

Removing Stars From a String

SimulationStackString

Acceptance: 79.7%

#2391Medium

Minimum Amount of Time to Collect Garbage

ArrayPrefix SumString

Acceptance: 85.2%

#2393Medium

Count Strictly Increasing Subarrays

ArrayDynamic ProgrammingMath

Acceptance: 70.8%

#2394Medium

Employees With Deductions

Database

Acceptance: 41.0%

#2396Medium

Strictly Palindromic Number

BrainteaserMathTwo Pointers

Acceptance: 90.3%

#2397Medium

Maximum Rows Covered by Columns

ArrayBacktrackingBit Manipulation+2

Acceptance: 58.4%

#2400Medium

Number of Ways to Reach a Position After Exactly k Steps

CombinatoricsDynamic ProgrammingMath

Acceptance: 37.4%

#2401Medium

Longest Nice Subarray

ArrayBit ManipulationSliding Window

Acceptance: 64.8%

#2405Medium

Optimal Partition of String

GreedyHash TableString

Acceptance: 78.0%

#2406Medium

Divide Intervals Into Minimum Number of Groups

ArrayGreedyHeap (Priority Queue)+3

Acceptance: 63.7%

#2408Medium

Design SQL

ArrayDesignHash Table+1

Acceptance: 63.9%

#2410Medium

Maximum Matching of Players With Trainers

ArrayGreedySorting+1

Acceptance: 75.2%

#2411Medium

Smallest Subarrays With Maximum Bitwise OR

ArrayBinary SearchBit Manipulation+1

Acceptance: 62.0%

#2414Medium

Length of the Longest Alphabetical Continuous Substring

String

Acceptance: 61.0%

#2415Medium

Reverse Odd Levels of Binary Tree

Binary TreeBreadth-First SearchDepth-First Search+1

Acceptance: 86.7%

#2417Medium

Closest Fair Integer

EnumerationMath

Acceptance: 43.7%

#2419Medium

Longest Subarray With Maximum Bitwise AND

ArrayBit ManipulationBrainteaser

Acceptance: 65.4%

#2420Medium

Find All Good Indices

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 40.8%

#2422Medium

Merge Operations to Turn Array Into a Palindrome

ArrayGreedyTwo Pointers

Acceptance: 69.0%

#2424Medium

Longest Uploaded Prefix

Binary Indexed TreeBinary SearchDesign+4

Acceptance: 55.5%

#2425Medium

Bitwise XOR of All Pairings

ArrayBit ManipulationBrainteaser

Acceptance: 66.9%

#2428Medium

Maximum Sum of an Hourglass

ArrayMatrixPrefix Sum

Acceptance: 77.1%

#2429Medium

Minimize XOR

Bit ManipulationGreedy

Acceptance: 62.4%

#2431Medium

Maximize Total Tastiness of Purchased Fruits

ArrayDynamic Programming

Acceptance: 64.6%

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