Solutions & Explanations

Browse 4,029+ detailed solutions with multiple approaches, code in Python, Java, C++ and more.

4,029 Solutions961 Easy2102 Medium966 Hard

Title	Difficulty	Acceptance	Topics	Solution
2122. Recover the Original Array	Hard	42.0%	Array Enumeration+3	Read
2123. Minimum Operations to Remove Adjacent Ones in Matrix	Hard	42.5%	Array Graph+1	Read
2127. Maximum Employees to Be Invited to a Meeting	Hard	61.8%	Depth-First Search Graph+1	Read
2132. Stamping the Grid	Hard	35.7%	Array Greedy+2	Read
2136. Earliest Possible Day of Full Bloom	Hard	71.4%	Array Greedy+1	Read
2141. Maximum Running Time of N Computers	Hard	56.4%	Array Binary Search+2	Read
2143. Choose Numbers From Two Arrays in Range	Hard	51.4%	Array Dynamic Programming	Read
2147. Number of Ways to Divide a Long Corridor	Hard	54.6%	Dynamic Programming Math+1	Read
2151. Maximum Good People Based on Statements	Hard	52.9%	Array Backtracking+2	Read
2153. The Number of Passengers in Each Bus II	Hard	39.2%	Database	Read
2156. Find Substring With Given Hash Value	Hard	26.7%	Hash Function Rolling Hash+2	Read
2157. Groups of Strings	Hard	28.2%	Bit Manipulation String+1	Read
2158. Amount of New Area Painted Each Day	Hard	55.3%	Array Ordered Set+1	Read
2163. Minimum Difference in Sums After Removal of Elements	Hard	69.8%	Array Dynamic Programming+1	Read
2167. Minimum Time to Remove All Cars Containing Illegal Goods	Hard	42.2%	Dynamic Programming String	Read
2172. Maximum AND Sum of Array	Hard	50.8%	Array Bit Manipulation+2	Read
2173. Longest Winning Streak	Hard	52.9%	Database	Read
2179. Count Good Triplets in an Array	Hard	65.2%	Array Binary Indexed Tree+5	Read
2183. Count Array Pairs Divisible by K	Hard	30.7%	Array Math+1	Read
2188. Minimum Time to Finish the Race	Hard	43.4%	Array Dynamic Programming	Read
2193. Minimum Number of Moves to Make Palindrome	Hard	52.7%	Binary Indexed Tree Greedy+2	Read
2197. Replace Non-Coprime Numbers in Array	Hard	57.7%	Array Math+2	Read
2199. Finding the Topic of Each Post	Hard	49.3%	Database	Read
2203. Minimum Weighted Subgraph With the Required Paths	Hard	43.2%	Graph Shortest Path	Read
2204. Distance to a Cycle in Undirected Graph	Hard	73.4%	Breadth-First Search Depth-First Search+2	Read
2209. Minimum White Tiles After Covering With Carpets	Hard	39.3%	Dynamic Programming Prefix Sum+1	Read
2213. Longest Substring of One Repeating Character	Hard	65.8%	Array Ordered Set+2	Read
2218. Maximum Value of K Coins From Piles	Hard	60.5%	Array Dynamic Programming+1	Read
2223. Sum of Scores of Built Strings	Hard	50.4%	Binary Search Hash Function+4	Read
2227. Encrypt and Decrypt Strings	Hard	38.8%	Array Design+3	Read
2234. Maximum Total Beauty of the Gardens	Hard	30.4%	Array Binary Search+3	Read
2242. Maximum Score of a Node Sequence	Hard	40.5%	Array Enumeration+2	Read
2246. Longest Path With Different Adjacent Characters	Hard	54.2%	Array Depth-First Search+4	Read
2247. Maximum Cost of Trip With K Highways	Hard	50.2%	Bit Manipulation Bitmask+2	Read
2251. Number of Flowers in Full Bloom	Hard	57.8%	Array Binary Search+4	Read
2252. Dynamic Pivoting of a Table	Hard	56.0%	Database	Read
2253. Dynamic Unpivoting of a Table	Hard	66.9%	Database	Read
2254. Design Video Sharing Platform	Hard	64.1%	Design Hash Table+2	Read
2258. Escape the Spreading Fire	Hard	39.1%	Array Binary Search+2	Read
2262. Total Appeal of A String	Hard	56.4%	Dynamic Programming Hash Table+1	Read
2263. Make Array Non-decreasing or Non-increasing	Hard	64.7%	Dynamic Programming Greedy	Read
2267. Check if There Is a Valid Parentheses String Path	Hard	40.7%	Array Dynamic Programming+1	Read
2272. Substring With Largest Variance	Hard	46.1%	Array Dynamic Programming	Read
2276. Count Integers in Intervals	Hard	36.1%	Design Ordered Set+1	Read
2277. Closest Node to Path in Tree	Hard	62.1%	Array Breadth-First Search+2	Read
2281. Sum of Total Strength of Wizards	Hard	29.8%	Array Monotonic Stack+2	Read
2286. Booking Concert Tickets in Groups	Hard	20.1%	Binary Indexed Tree Binary Search+2	Read
2290. Minimum Obstacle Removal to Reach Corner	Hard	71.1%	Array Breadth-First Search+4	Read
2296. Design a Text Editor	Hard	51.5%	Design Doubly-Linked List+4	Read
2301. Match Substring After Replacement	Hard	43.3%	Array Hash Table+2	Read

#2122Hard

Recover the Original Array

ArrayEnumerationHash Table+2

Acceptance: 42.0%

#2123Hard

Minimum Operations to Remove Adjacent Ones in Matrix

ArrayGraphMatrix

Acceptance: 42.5%

#2127Hard

Maximum Employees to Be Invited to a Meeting

Depth-First SearchGraphTopological Sort

Acceptance: 61.8%

#2132Hard

Stamping the Grid

ArrayGreedyMatrix+1

Acceptance: 35.7%

#2136Hard

Earliest Possible Day of Full Bloom

ArrayGreedySorting

Acceptance: 71.4%

#2141Hard

Maximum Running Time of N Computers

ArrayBinary SearchGreedy+1

Acceptance: 56.4%

#2143Hard

Choose Numbers From Two Arrays in Range

ArrayDynamic Programming

Acceptance: 51.4%

#2147Hard

Number of Ways to Divide a Long Corridor

Dynamic ProgrammingMathString

Acceptance: 54.6%

#2151Hard

Maximum Good People Based on Statements

ArrayBacktrackingBit Manipulation+1

Acceptance: 52.9%

#2153Hard

The Number of Passengers in Each Bus II

Database

Acceptance: 39.2%

#2156Hard

Find Substring With Given Hash Value

Hash FunctionRolling HashSliding Window+1

Acceptance: 26.7%

#2157Hard

Groups of Strings

Bit ManipulationStringUnion Find

Acceptance: 28.2%

#2158Hard

Amount of New Area Painted Each Day

ArrayOrdered SetSegment Tree

Acceptance: 55.3%

#2163Hard

Minimum Difference in Sums After Removal of Elements

ArrayDynamic ProgrammingHeap (Priority Queue)

Acceptance: 69.8%

#2167Hard

Minimum Time to Remove All Cars Containing Illegal Goods

Dynamic ProgrammingString

Acceptance: 42.2%

#2172Hard

Maximum AND Sum of Array

ArrayBit ManipulationBitmask+1

Acceptance: 50.8%

#2173Hard

Longest Winning Streak

Database

Acceptance: 52.9%

#2179Hard

Count Good Triplets in an Array

ArrayBinary Indexed TreeBinary Search+4

Acceptance: 65.2%

#2183Hard

Count Array Pairs Divisible by K

ArrayMathNumber Theory

Acceptance: 30.7%

#2188Hard

Minimum Time to Finish the Race

ArrayDynamic Programming

Acceptance: 43.4%

#2193Hard

Minimum Number of Moves to Make Palindrome

Binary Indexed TreeGreedyString+1

Acceptance: 52.7%

#2197Hard

Replace Non-Coprime Numbers in Array

ArrayMathNumber Theory+1

Acceptance: 57.7%

#2199Hard

Finding the Topic of Each Post

Database

Acceptance: 49.3%

#2203Hard

Minimum Weighted Subgraph With the Required Paths

GraphShortest Path

Acceptance: 43.2%

#2204Hard

Distance to a Cycle in Undirected Graph

Breadth-First SearchDepth-First SearchGraph+1

Acceptance: 73.4%

#2209Hard

Minimum White Tiles After Covering With Carpets

Dynamic ProgrammingPrefix SumString

Acceptance: 39.3%

#2213Hard

Longest Substring of One Repeating Character

ArrayOrdered SetSegment Tree+1

Acceptance: 65.8%

#2218Hard

Maximum Value of K Coins From Piles

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 60.5%

#2223Hard

Sum of Scores of Built Strings

Binary SearchHash FunctionRolling Hash+3

Acceptance: 50.4%

#2227Hard

Encrypt and Decrypt Strings

ArrayDesignHash Table+2

Acceptance: 38.8%

#2234Hard

Maximum Total Beauty of the Gardens

ArrayBinary SearchGreedy+2

Acceptance: 30.4%

#2242Hard

Maximum Score of a Node Sequence

ArrayEnumerationGraph+1

Acceptance: 40.5%

#2246Hard

Longest Path With Different Adjacent Characters

ArrayDepth-First SearchGraph+3

Acceptance: 54.2%

#2247Hard

Maximum Cost of Trip With K Highways

Bit ManipulationBitmaskDynamic Programming+1

Acceptance: 50.2%

#2251Hard

Number of Flowers in Full Bloom

ArrayBinary SearchHash Table+3

Acceptance: 57.8%

#2252Hard

Dynamic Pivoting of a Table

Database

Acceptance: 56.0%

#2253Hard

Dynamic Unpivoting of a Table

Database

Acceptance: 66.9%

#2254Hard

Design Video Sharing Platform

DesignHash TableOrdered Set+1

Acceptance: 64.1%

#2258Hard

Escape the Spreading Fire

ArrayBinary SearchBreadth-First Search+1

Acceptance: 39.1%

#2262Hard

Total Appeal of A String

Dynamic ProgrammingHash TableString

Acceptance: 56.4%

#2263Hard

Make Array Non-decreasing or Non-increasing

Dynamic ProgrammingGreedy

Acceptance: 64.7%

#2267Hard

Check if There Is a Valid Parentheses String Path

ArrayDynamic ProgrammingMatrix

Acceptance: 40.7%

#2272Hard

Substring With Largest Variance

ArrayDynamic Programming

Acceptance: 46.1%

#2276Hard

Count Integers in Intervals

DesignOrdered SetSegment Tree

Acceptance: 36.1%

#2277Hard

Closest Node to Path in Tree

ArrayBreadth-First SearchDepth-First Search+1

Acceptance: 62.1%

#2281Hard

Sum of Total Strength of Wizards

ArrayMonotonic StackPrefix Sum+1

Acceptance: 29.8%

#2286Hard

Booking Concert Tickets in Groups

Binary Indexed TreeBinary SearchDesign+1

Acceptance: 20.1%

#2290Hard

Minimum Obstacle Removal to Reach Corner

ArrayBreadth-First SearchGraph+3

Acceptance: 71.1%

#2296Hard

Design a Text Editor

DesignDoubly-Linked ListLinked List+3

Acceptance: 51.5%

#2301Hard

Match Substring After Replacement

ArrayHash TableString+1

Acceptance: 43.3%

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