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
2351. First Letter to Appear Twice	Easy	74.9%	Bit Manipulation Counting+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
2354. Number of Excellent Pairs	Hard	49.1%	Array Binary Search+2	Read
2355. Maximum Number of Books You Can Take	Hard	40.3%	Array Dynamic Programming+2	Read
2356. Number of Unique Subjects Taught by Each Teacher	Easy	89.1%	Database	Read
2357. Make Array Zero by Subtracting Equal Amounts	Easy	73.8%	Array Greedy+4	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
2360. Longest Cycle in a Graph	Hard	51.1%	Depth-First Search Graph+1	Read
2361. Minimum Costs Using the Train Line	Hard	77.7%	Array Dynamic Programming	Read
2362. Generate the Invoice	Hard	75.2%	Database	Read
2363. Merge Similar Items	Easy	77.4%	Array Hash Table+2	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
2366. Minimum Replacements to Sort the Array	Hard	53.4%	Array Greedy+1	Read
2367. Number of Arithmetic Triplets	Easy	85.4%	Array Enumeration+2	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
2371. Minimize Maximum Value in a Grid	Hard	70.1%	Array Graph+4	Read
2372. Calculate the Influence of Each Salesperson	Medium	83.2%	Database	Read
2373. Largest Local Values in a Matrix	Easy	87.8%	Array Matrix	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
2376. Count Special Integers	Hard	45.2%	Dynamic Programming Math	Read
2377. Sort the Olympic Table	Easy	79.1%	Database	Read
2378. Choose Edges to Maximize Score in a Tree	Medium	56.5%	Depth-First Search Dynamic Programming+1	Read
2379. Minimum Recolors to Get K Consecutive Black Blocks	Easy	68.6%	Sliding Window String	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
2382. Maximum Segment Sum After Removals	Hard	50.1%	Array Ordered Set+2	Read
2383. Minimum Hours of Training to Win a Competition	Easy	42.5%	Array Greedy	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
2386. Find the K-Sum of an Array	Hard	42.0%	Array Heap (Priority Queue)+1	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
2389. Longest Subsequence With Limited Sum	Easy	73.5%	Array Binary Search+3	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
2392. Build a Matrix With Conditions	Hard	79.5%	Array Graph+2	Read
2393. Count Strictly Increasing Subarrays	Medium	70.8%	Array Dynamic Programming+1	Read
2394. Employees With Deductions	Medium	41.0%	Database	Read
2395. Find Subarrays With Equal Sum	Easy	66.9%	Array Hash Table	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
2398. Maximum Number of Robots Within Budget	Hard	38.8%	Array Binary Search+5	Read
2399. Check Distances Between Same Letters	Easy	71.5%	Array Hash Table+1	Read
2400. Number of Ways to Reach a Position After Exactly k Steps	Medium	37.4%	Combinatorics Dynamic Programming+1	Read

#2351Easy

First Letter to Appear Twice

Bit ManipulationCountingHash Table+1

Acceptance: 74.9%

#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%

#2354Hard

Number of Excellent Pairs

ArrayBinary SearchBit Manipulation+1

Acceptance: 49.1%

#2355Hard

Maximum Number of Books You Can Take

ArrayDynamic ProgrammingMonotonic Stack+1

Acceptance: 40.3%

#2356Easy

Number of Unique Subjects Taught by Each Teacher

Database

Acceptance: 89.1%

#2357Easy

Make Array Zero by Subtracting Equal Amounts

ArrayGreedyHash Table+3

Acceptance: 73.8%

#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%

#2360Hard

Longest Cycle in a Graph

Depth-First SearchGraphTopological Sort

Acceptance: 51.1%

#2361Hard

Minimum Costs Using the Train Line

ArrayDynamic Programming

Acceptance: 77.7%

#2362Hard

Generate the Invoice

Database

Acceptance: 75.2%

#2363Easy

Merge Similar Items

ArrayHash TableOrdered Set+1

Acceptance: 77.4%

#2364Medium

Count Number of Bad Pairs

ArrayCountingHash Table+1

Acceptance: 54.2%

#2365Medium

Task Scheduler II

ArrayHash TableSimulation

Acceptance: 54.7%

#2366Hard

Minimum Replacements to Sort the Array

ArrayGreedyMath

Acceptance: 53.4%

#2367Easy

Number of Arithmetic Triplets

ArrayEnumerationHash Table+1

Acceptance: 85.4%

#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%

#2371Hard

Minimize Maximum Value in a Grid

ArrayGraphMatrix+3

Acceptance: 70.1%

#2372Medium

Calculate the Influence of Each Salesperson

Database

Acceptance: 83.2%

#2373Easy

Largest Local Values in a Matrix

ArrayMatrix

Acceptance: 87.8%

#2374Medium

Node With Highest Edge Score

GraphHash Table

Acceptance: 49.3%

#2375Medium

Construct Smallest Number From DI String

BacktrackingGreedyStack+1

Acceptance: 85.6%

#2376Hard

Count Special Integers

Dynamic ProgrammingMath

Acceptance: 45.2%

#2377Easy

Sort the Olympic Table

Database

Acceptance: 79.1%

#2378Medium

Choose Edges to Maximize Score in a Tree

Depth-First SearchDynamic ProgrammingTree

Acceptance: 56.5%

#2379Easy

Minimum Recolors to Get K Consecutive Black Blocks

Sliding WindowString

Acceptance: 68.6%

#2380Medium

Time Needed to Rearrange a Binary String

Dynamic ProgrammingSimulationString

Acceptance: 53.3%

#2381Medium

Shifting Letters II

ArrayPrefix SumString

Acceptance: 53.6%

#2382Hard

Maximum Segment Sum After Removals

ArrayOrdered SetPrefix Sum+1

Acceptance: 50.1%

#2383Easy

Minimum Hours of Training to Win a Competition

ArrayGreedy

Acceptance: 42.5%

#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%

#2386Hard

Find the K-Sum of an Array

ArrayHeap (Priority Queue)Sorting

Acceptance: 42.0%

#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%

#2389Easy

Longest Subsequence With Limited Sum

ArrayBinary SearchGreedy+2

Acceptance: 73.5%

#2390Medium

Removing Stars From a String

SimulationStackString

Acceptance: 79.7%

#2391Medium

Minimum Amount of Time to Collect Garbage

ArrayPrefix SumString

Acceptance: 85.2%

#2392Hard

Build a Matrix With Conditions

ArrayGraphMatrix+1

Acceptance: 79.5%

#2393Medium

Count Strictly Increasing Subarrays

ArrayDynamic ProgrammingMath

Acceptance: 70.8%

#2394Medium

Employees With Deductions

Database

Acceptance: 41.0%

#2395Easy

Find Subarrays With Equal Sum

ArrayHash Table

Acceptance: 66.9%

#2396Medium

Strictly Palindromic Number

BrainteaserMathTwo Pointers

Acceptance: 90.3%

#2397Medium

Maximum Rows Covered by Columns

ArrayBacktrackingBit Manipulation+2

Acceptance: 58.4%

#2398Hard

Maximum Number of Robots Within Budget

ArrayBinary SearchHeap (Priority Queue)+4

Acceptance: 38.8%

#2399Easy

Check Distances Between Same Letters

ArrayHash TableString

Acceptance: 71.5%

#2400Medium

Number of Ways to Reach a Position After Exactly k Steps

CombinatoricsDynamic ProgrammingMath

Acceptance: 37.4%

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