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
3149. Find the Minimum Cost Array Permutation	Hard	26.1%	Array Bit Manipulation+2	Read
3154. Find Number of Ways to Reach the K-th Stair	Hard	38.2%	Bit Manipulation Combinatorics+3	Read
3156. Employee Task Duration and Concurrent Tasks	Hard	54.0%	Database	Read
3161. Block Placement Queries	Hard	41.0%	Array Binary Indexed Tree+2	Read
3165. Maximum Sum of Subsequence With Non-adjacent Elements	Hard	15.7%	Array Divide and Conquer+2	Read
3171. Find Subarray With Bitwise OR Closest to K	Hard	31.5%	Array Binary Search+2	Read
3177. Find the Maximum Length of a Good Subsequence II	Hard	25.2%	Array Dynamic Programming+1	Read
3181. Maximum Total Reward Using Operations II	Hard	21.9%	Array Bit Manipulation+1	Read
3187. Peaks in Array	Hard	27.9%	Array Binary Indexed Tree+1	Read
3188. Find Top Scoring Students II	Hard	37.8%	Database	Read
3193. Count the Number of Inversions	Hard	31.9%	Array Dynamic Programming	Read
3197. Find the Minimum Area to Cover All Ones II	Hard	63.5%	Array Enumeration+1	Read
3203. Find Minimum Diameter After Merging Two Trees	Hard	57.1%	Breadth-First Search Depth-First Search+2	Read
3209. Number of Subarrays With AND Value of K	Hard	35.7%	Array Binary Search+2	Read
3213. Construct String with Minimum Cost	Hard	19.0%	Array Dynamic Programming+2	Read
3214. Year on Year Growth Rate	Hard	51.7%	Database	Read
3219. Minimum Cost for Cutting Cake II	Hard	54.2%	Array Greedy+1	Read
3225. Maximum Score From Grid Operations	Hard	63.5%	Array Dynamic Programming+2	Read
3229. Minimum Operations to Make Array Equal to Target	Hard	41.4%	Array Dynamic Programming+3	Read
3231. Minimum Number of Increasing Subsequence to Be Removed	Hard	47.9%	Array Binary Search	Read
3235. Check if the Rectangle Corner Is Reachable	Hard	24.4%	Array Breadth-First Search+4	Read
3236. CEO Subordinate Hierarchy	Hard	72.3%	Database	Read
3241. Time Taken to Mark All Nodes	Hard	28.9%	Depth-First Search Dynamic Programming+2	Read
3244. Shortest Distance After Road Addition Queries II	Hard	26.5%	Array Graph+2	Read
3245. Alternating Groups III	Hard	18.9%	Array Binary Indexed Tree	Read
3250. Find the Count of Monotonic Pairs I	Hard	47.6%	Array Combinatorics+3	Read
3251. Find the Count of Monotonic Pairs II	Hard	24.7%	Array Combinatorics+3	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
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
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
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
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
3279. Maximum Total Area Occupied by Pistons	Hard	41.3%	Array Counting+4	Read
3283. Maximum Number of Moves to Kill All Pawns	Hard	33.7%	Array Bit Manipulation+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
3292. Minimum Number of Valid Strings to Form Target II	Hard	21.1%	Array Binary Search+6	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
3303. Find the Occurrence of First Almost Equal Substring	Hard	16.0%	String String Matching	Read
3307. Find the K-th Character in String Game II	Hard	48.5%	Bit Manipulation Math+1	Read
3311. Construct 2D Grid Matching Graph Layout	Hard	29.3%	Array Graph+2	Read
3312. Sorted GCD Pair Queries	Hard	58.4%	Array Binary Search+6	Read

#3149Hard

Find the Minimum Cost Array Permutation

ArrayBit ManipulationBitmask+1

Acceptance: 26.1%

#3154Hard

Find Number of Ways to Reach the K-th Stair

Bit ManipulationCombinatoricsDynamic Programming+2

Acceptance: 38.2%

#3156Hard

Employee Task Duration and Concurrent Tasks

Database

Acceptance: 54.0%

#3161Hard

Block Placement Queries

ArrayBinary Indexed TreeBinary Search+1

Acceptance: 41.0%

#3165Hard

Maximum Sum of Subsequence With Non-adjacent Elements

ArrayDivide and ConquerDynamic Programming+1

Acceptance: 15.7%

#3171Hard

Find Subarray With Bitwise OR Closest to K

ArrayBinary SearchBit Manipulation+1

Acceptance: 31.5%

#3177Hard

Find the Maximum Length of a Good Subsequence II

ArrayDynamic ProgrammingHash Table

Acceptance: 25.2%

#3181Hard

Maximum Total Reward Using Operations II

ArrayBit ManipulationDynamic Programming

Acceptance: 21.9%

#3187Hard

Peaks in Array

ArrayBinary Indexed TreeSegment Tree

Acceptance: 27.9%

#3188Hard

Find Top Scoring Students II

Database

Acceptance: 37.8%

#3193Hard

Count the Number of Inversions

ArrayDynamic Programming

Acceptance: 31.9%

#3197Hard

Find the Minimum Area to Cover All Ones II

ArrayEnumerationMatrix

Acceptance: 63.5%

#3203Hard

Find Minimum Diameter After Merging Two Trees

Breadth-First SearchDepth-First SearchGraph+1

Acceptance: 57.1%

#3209Hard

Number of Subarrays With AND Value of K

ArrayBinary SearchBit Manipulation+1

Acceptance: 35.7%

#3213Hard

Construct String with Minimum Cost

ArrayDynamic ProgrammingString+1

Acceptance: 19.0%

#3214Hard

Year on Year Growth Rate

Database

Acceptance: 51.7%

#3219Hard

Minimum Cost for Cutting Cake II

ArrayGreedySorting

Acceptance: 54.2%

#3225Hard

Maximum Score From Grid Operations

ArrayDynamic ProgrammingMatrix+1

Acceptance: 63.5%

#3229Hard

Minimum Operations to Make Array Equal to Target

ArrayDynamic ProgrammingGreedy+2

Acceptance: 41.4%

#3231Hard

Minimum Number of Increasing Subsequence to Be Removed

ArrayBinary Search

Acceptance: 47.9%

#3235Hard

Check if the Rectangle Corner Is Reachable

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 24.4%

#3236Hard

CEO Subordinate Hierarchy

Database

Acceptance: 72.3%

#3241Hard

Time Taken to Mark All Nodes

Depth-First SearchDynamic ProgrammingGraph+1

Acceptance: 28.9%

#3244Hard

Shortest Distance After Road Addition Queries II

ArrayGraphGreedy+1

Acceptance: 26.5%

#3245Hard

Alternating Groups III

ArrayBinary Indexed Tree

Acceptance: 18.9%

#3250Hard

Find the Count of Monotonic Pairs I

ArrayCombinatoricsDynamic Programming+2

Acceptance: 47.6%

#3251Hard

Find the Count of Monotonic Pairs II

ArrayCombinatoricsDynamic Programming+2

Acceptance: 24.7%

#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%

#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%

#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%

#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%

#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%

#3279Hard

Maximum Total Area Occupied by Pistons

ArrayCountingHash Table+3

Acceptance: 41.3%

#3283Hard

Maximum Number of Moves to Kill All Pawns

ArrayBit ManipulationBitmask+3

Acceptance: 33.7%

#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%

#3292Hard

Minimum Number of Valid Strings to Form Target II

ArrayBinary SearchDynamic Programming+5

Acceptance: 21.1%

#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%

#3303Hard

Find the Occurrence of First Almost Equal Substring

StringString Matching

Acceptance: 16.0%

#3307Hard

Find the K-th Character in String Game II

Bit ManipulationMathRecursion

Acceptance: 48.5%

#3311Hard

Construct 2D Grid Matching Graph Layout

ArrayGraphHash Table+1

Acceptance: 29.3%

#3312Hard

Sorted GCD Pair Queries

ArrayBinary SearchCombinatorics+5

Acceptance: 58.4%

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