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
1251. Average Selling Price	Easy	37.1%	Database	Read
1252. Cells with Odd Values in a Matrix	Easy	79.7%	Array Math+1	Read
1253. Reconstruct a 2-Row Binary Matrix	Medium	49.4%	Array Greedy+1	Read
1254. Number of Closed Islands	Medium	67.1%	Array Breadth-First Search+3	Read
1255. Maximum Score Words Formed by Letters	Hard	81.9%	Array Backtracking+4	Read
1256. Encode Number	Medium	70.0%	Bit Manipulation Math+1	Read
1257. Smallest Common Region	Medium	68.6%	Array Breadth-First Search+4	Read
1258. Synonymous Sentences	Medium	57.2%	Array Backtracking+3	Read
1259. Handshakes That Don't Cross	Hard	61.1%	Dynamic Programming Math	Read
1260. Shift 2D Grid	Easy	74.3%	Array Matrix+1	Read
1261. Find Elements in a Contaminated Binary Tree	Medium	84.1%	Binary Tree Breadth-First Search+4	Read
1262. Greatest Sum Divisible by Three	Medium	57.1%	Array Dynamic Programming+2	Read
1263. Minimum Moves to Move a Box to Their Target Location	Hard	49.7%	Array Breadth-First Search+2	Read
1264. Page Recommendations	Medium	65.3%	Database	Read
1265. Print Immutable Linked List in Reverse	Medium	94.0%	Linked List Recursion+2	Read
1266. Minimum Time Visiting All Points	Easy	84.8%	Array Geometry+1	Read
1267. Count Servers that Communicate	Medium	73.5%	Array Breadth-First Search+4	Read
1268. Search Suggestions System	Medium	65.1%	Array Binary Search+4	Read
1269. Number of Ways to Stay in the Same Place After Some Steps	Hard	50.2%	Dynamic Programming	Read
1270. All People Report to the Given Manager	Medium	84.5%	Database	Read
1271. Hexspeak	Easy	58.2%	Math String	Read
1272. Remove Interval	Medium	67.2%	Array	Read
1273. Delete Tree Nodes	Medium	61.2%	Array Breadth-First Search+2	Read
1274. Number of Ships in a Rectangle	Hard	68.7%	Array Divide and Conquer+1	Read
1275. Find Winner on a Tic Tac Toe Game	Easy	54.6%	Array Hash Table+2	Read
1276. Number of Burgers with No Waste of Ingredients	Medium	52.7%	Math	Read
1277. Count Square Submatrices with All Ones	Medium	80.7%	Array Dynamic Programming+1	Read
1278. Palindrome Partitioning III	Hard	62.2%	Dynamic Programming String	Read
1279. Traffic Light Controlled Intersection	Easy	72.8%	Concurrency	Read
1280. Students and Examinations	Easy	59.6%	Database	Read
1281. Subtract the Product and Sum of Digits of an Integer	Easy	86.6%	Math	Read
1282. Group the People Given the Group Size They Belong To	Medium	87.4%	Array Greedy+1	Read
1283. Find the Smallest Divisor Given a Threshold	Medium	66.8%	Array Binary Search	Read
1284. Minimum Number of Flips to Convert Binary Matrix to Zero Matrix	Hard	72.9%	Array Bit Manipulation+3	Read
1285. Find the Start and End Number of Continuous Ranges	Medium	82.1%	Database	Read
1286. Iterator for Combination	Medium	72.7%	Backtracking Design+2	Read
1287. Element Appearing More Than 25% In Sorted Array	Easy	61.5%	Array	Read
1288. Remove Covered Intervals	Medium	60.1%	Array Sorting	Read
1289. Minimum Falling Path Sum II	Hard	63.2%	Array Dynamic Programming+1	Read
1290. Convert Binary Number in a Linked List to Integer	Easy	82.3%	Linked List Math	Read
1291. Sequential Digits	Medium	68.6%	Enumeration	Read
1292. Maximum Side Length of a Square with Sum Less than or Equal to Threshold	Medium	65.4%	Array Binary Search+2	Read
1293. Shortest Path in a Grid with Obstacles Elimination	Hard	46.2%	Array Breadth-First Search+1	Read
1294. Weather Type in Each Country	Easy	66.8%	Database	Read
1295. Find Numbers with Even Number of Digits	Easy	79.7%	Array Math	Read
1296. Divide Array in Sets of K Consecutive Numbers	Medium	59.2%	Array Greedy+2	Read
1297. Maximum Number of Occurrences of a Substring	Medium	54.9%	Hash Table Sliding Window+1	Read
1298. Maximum Candies You Can Get from Boxes	Hard	67.2%	Array Breadth-First Search+1	Read
1299. Replace Elements with Greatest Element on Right Side	Easy	72.6%	Array	Read
1300. Sum of Mutated Array Closest to Target	Medium	46.2%	Array Binary Search+1	Read

#1251Easy

Average Selling Price

Database

Acceptance: 37.1%

#1252Easy

Cells with Odd Values in a Matrix

ArrayMathSimulation

Acceptance: 79.7%

#1253Medium

Reconstruct a 2-Row Binary Matrix

ArrayGreedyMatrix

Acceptance: 49.4%

#1254Medium

Number of Closed Islands

ArrayBreadth-First SearchDepth-First Search+2

Acceptance: 67.1%

#1255Hard

Maximum Score Words Formed by Letters

ArrayBacktrackingBit Manipulation+3

Acceptance: 81.9%

#1256Medium

Encode Number

Bit ManipulationMathString

Acceptance: 70.0%

#1257Medium

Smallest Common Region

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 68.6%

#1258Medium

Synonymous Sentences

ArrayBacktrackingHash Table+2

Acceptance: 57.2%

#1259Hard

Handshakes That Don't Cross

Dynamic ProgrammingMath

Acceptance: 61.1%

#1260Easy

Shift 2D Grid

ArrayMatrixSimulation

Acceptance: 74.3%

#1261Medium

Find Elements in a Contaminated Binary Tree

Binary TreeBreadth-First SearchDepth-First Search+3

Acceptance: 84.1%

#1262Medium

Greatest Sum Divisible by Three

ArrayDynamic ProgrammingGreedy+1

Acceptance: 57.1%

#1263Hard

Minimum Moves to Move a Box to Their Target Location

ArrayBreadth-First SearchHeap (Priority Queue)+1

Acceptance: 49.7%

#1264Medium

Page Recommendations

Database

Acceptance: 65.3%

#1265Medium

Print Immutable Linked List in Reverse

Linked ListRecursionStack+1

Acceptance: 94.0%

#1266Easy

Minimum Time Visiting All Points

ArrayGeometryMath

Acceptance: 84.8%

#1267Medium

Count Servers that Communicate

ArrayBreadth-First SearchCounting+3

Acceptance: 73.5%

#1268Medium

Search Suggestions System

ArrayBinary SearchHeap (Priority Queue)+3

Acceptance: 65.1%

#1269Hard

Number of Ways to Stay in the Same Place After Some Steps

Dynamic Programming

Acceptance: 50.2%

#1270Medium

All People Report to the Given Manager

Database

Acceptance: 84.5%

#1271Easy

Hexspeak

MathString

Acceptance: 58.2%

#1272Medium

Remove Interval

Array

Acceptance: 67.2%

#1273Medium

Delete Tree Nodes

ArrayBreadth-First SearchDepth-First Search+1

Acceptance: 61.2%

#1274Hard

Number of Ships in a Rectangle

ArrayDivide and ConquerInteractive

Acceptance: 68.7%

#1275Easy

Find Winner on a Tic Tac Toe Game

ArrayHash TableMatrix+1

Acceptance: 54.6%

#1276Medium

Number of Burgers with No Waste of Ingredients

Math

Acceptance: 52.7%

#1277Medium

Count Square Submatrices with All Ones

ArrayDynamic ProgrammingMatrix

Acceptance: 80.7%

#1278Hard

Palindrome Partitioning III

Dynamic ProgrammingString

Acceptance: 62.2%

#1279Easy

Traffic Light Controlled Intersection

Concurrency

Acceptance: 72.8%

#1280Easy

Students and Examinations

Database

Acceptance: 59.6%

#1281Easy

Subtract the Product and Sum of Digits of an Integer

Math

Acceptance: 86.6%

#1282Medium

Group the People Given the Group Size They Belong To

ArrayGreedyHash Table

Acceptance: 87.4%

#1283Medium

Find the Smallest Divisor Given a Threshold

ArrayBinary Search

Acceptance: 66.8%

#1284Hard

Minimum Number of Flips to Convert Binary Matrix to Zero Matrix

ArrayBit ManipulationBreadth-First Search+2

Acceptance: 72.9%

#1285Medium

Find the Start and End Number of Continuous Ranges

Database

Acceptance: 82.1%

#1286Medium

Iterator for Combination

BacktrackingDesignIterator+1

Acceptance: 72.7%

#1287Easy

Element Appearing More Than 25% In Sorted Array

Array

Acceptance: 61.5%

#1288Medium

Remove Covered Intervals

ArraySorting

Acceptance: 60.1%

#1289Hard

Minimum Falling Path Sum II

ArrayDynamic ProgrammingMatrix

Acceptance: 63.2%

#1290Easy

Convert Binary Number in a Linked List to Integer

Linked ListMath

Acceptance: 82.3%

#1291Medium

Sequential Digits

Enumeration

Acceptance: 68.6%

#1292Medium

Maximum Side Length of a Square with Sum Less than or Equal to Threshold

ArrayBinary SearchMatrix+1

Acceptance: 65.4%

#1293Hard

Shortest Path in a Grid with Obstacles Elimination

ArrayBreadth-First SearchMatrix

Acceptance: 46.2%

#1294Easy

Weather Type in Each Country

Database

Acceptance: 66.8%

#1295Easy

Find Numbers with Even Number of Digits

ArrayMath

Acceptance: 79.7%

#1296Medium

Divide Array in Sets of K Consecutive Numbers

ArrayGreedyHash Table+1

Acceptance: 59.2%

#1297Medium

Maximum Number of Occurrences of a Substring

Hash TableSliding WindowString

Acceptance: 54.9%

#1298Hard

Maximum Candies You Can Get from Boxes

ArrayBreadth-First SearchGraph

Acceptance: 67.2%

#1299Easy

Replace Elements with Greatest Element on Right Side

Array

Acceptance: 72.6%

#1300Medium

Sum of Mutated Array Closest to Target

ArrayBinary SearchSorting

Acceptance: 46.2%

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Master DSA with Step-by-Step Solutions

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Try the problem first: Spend at least 20 minutes before reading the solution
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Code it yourself: After understanding the approach, close the solution and implement from memory
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