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
2963. Count the Number of Good Partitions	Hard	49.3%	Array Combinatorics+2	Read
2968. Apply Operations to Maximize Frequency Score	Hard	39.3%	Array Binary Search+3	Read
2969. Minimum Number of Coins for Fruits II	Hard	48.2%	Array Dynamic Programming+3	Read
2972. Count the Number of Incremovable Subarrays II	Hard	39.8%	Array Binary Search+1	Read
2973. Find Number of Coins to Place in Tree Nodes	Hard	37.4%	Depth-First Search Dynamic Programming+3	Read
2977. Minimum Cost to Convert String II	Hard	59.1%	Array Dynamic Programming+4	Read
2983. Palindrome Rearrangement Queries	Hard	25.1%	Hash Table Prefix Sum+1	Read
2991. Top Three Wineries	Hard	55.8%	Database	Read
2994. Friday Purchases II	Hard	74.6%	Database	Read
2995. Viewers Turned Streamers	Hard	43.4%	Database	Read
2999. Count the Number of Powerful Integers	Hard	46.3%	Dynamic Programming Math+1	Read
3003. Maximize the Number of Partitions After Operations	Hard	53.5%	Bit Manipulation Bitmask+2	Read
3008. Find Beautiful Indices in the Given Array II	Hard	28.3%	Binary Search Hash Function+4	Read
3009. Maximum Number of Intersections on the Chart	Hard	45.5%	Array Binary Indexed Tree+2	Read
3013. Divide an Array Into Subarrays With Minimum Cost II	Hard	54.7%	Array Hash Table+2	Read
3017. Count the Number of Houses at a Certain Distance II	Hard	23.7%	Graph Prefix Sum	Read
3018. Maximum Number of Removal Queries That Can Be Processed I	Hard	44.8%	Array Dynamic Programming	Read
3022. Minimize OR of Remaining Elements Using Operations	Hard	29.6%	Array Bit Manipulation+1	Read
3027. Find the Number of Ways to Place People II	Hard	64.4%	Array Enumeration+3	Read
3031. Minimum Time to Revert Word to Initial State II	Hard	35.1%	Hash Function Rolling Hash+2	Read
3036. Number of Subarrays That Match a Pattern II	Hard	34.1%	Array Hash Function+2	Read
3037. Find Pattern in Infinite Stream II	Hard	67.5%	Array Hash Function+3	Read
3041. Maximize Consecutive Elements in an Array After Modification	Hard	33.7%	Array Dynamic Programming+1	Read
3045. Count Prefix and Suffix Pairs II	Hard	28.2%	Array Hash Function+4	Read
3049. Earliest Second to Mark Indices II	Hard	22.6%	Array Binary Search+2	Read
3052. Maximize Items	Hard	72.0%	Database	Read
3057. Employees Project Allocation	Hard	68.4%	Database	Read
3060. User Activities within Time Bounds	Hard	40.6%	Database	Read
3061. Calculate Trapping Rain Water	Hard	81.1%	Database	Read
3068. Find the Maximum Sum of Node Values	Hard	69.5%	Array Bit Manipulation+4	Read
3072. Distribute Elements Into Two Arrays II	Hard	32.1%	Array Binary Indexed Tree+2	Read
3077. Maximum Strength of K Disjoint Subarrays	Hard	28.2%	Array Dynamic Programming+1	Read
3082. Find the Sum of the Power of All Subsequences	Hard	38.1%	Array Dynamic Programming	Read
3086. Minimum Moves to Pick K Ones	Hard	21.6%	Array Greedy+2	Read
3088. Make String Anti-palindrome	Hard	46.6%	Counting Sort Greedy+2	Read
3093. Longest Common Suffix Queries	Hard	52.8%	Array String+1	Read
3098. Find the Sum of Subsequence Powers	Hard	25.1%	Array Dynamic Programming+1	Read
3102. Minimize Manhattan Distances	Hard	32.9%	Array Geometry+3	Read
3103. Find Trending Hashtags II	Hard	64.7%	Database	Read
3104. Find Longest Self-Contained Substring	Hard	58.6%	Binary Search Hash Table+2	Read
3108. Minimum Cost Walk in Weighted Graph	Hard	68.3%	Array Bit Manipulation+2	Read
3113. Find the Number of Subarrays Where Boundary Elements Are Maximum	Hard	34.2%	Array Binary Search+2	Read
3116. Kth Smallest Amount With Single Denomination Combination	Hard	50.3%	Array Binary Search+4	Read
3117. Minimum Sum of Values by Dividing Array	Hard	27.9%	Array Binary Search+4	Read
3123. Find Edges in Shortest Paths	Hard	47.0%	Breadth-First Search Depth-First Search+3	Read
3130. Find All Possible Stable Binary Arrays II	Hard	58.4%	Dynamic Programming Prefix Sum	Read
3134. Find the Median of the Uniqueness Array	Hard	30.0%	Array Binary Search+2	Read
3139. Minimum Cost to Equalize Array	Hard	18.8%	Array Enumeration+1	Read
3141. Maximum Hamming Distances	Hard	50.0%	Array Bit Manipulation+1	Read
3145. Find Products of Elements of Big Array	Hard	24.4%	Array Binary Search+1	Read

#2963Hard

Count the Number of Good Partitions

ArrayCombinatoricsHash Table+1

Acceptance: 49.3%

#2968Hard

Apply Operations to Maximize Frequency Score

ArrayBinary SearchPrefix Sum+2

Acceptance: 39.3%

#2969Hard

Minimum Number of Coins for Fruits II

ArrayDynamic ProgrammingHeap (Priority Queue)+2

Acceptance: 48.2%

#2972Hard

Count the Number of Incremovable Subarrays II

ArrayBinary SearchTwo Pointers

Acceptance: 39.8%

#2973Hard

Find Number of Coins to Place in Tree Nodes

Depth-First SearchDynamic ProgrammingHeap (Priority Queue)+2

Acceptance: 37.4%

#2977Hard

Minimum Cost to Convert String II

ArrayDynamic ProgrammingGraph+3

Acceptance: 59.1%

#2983Hard

Palindrome Rearrangement Queries

Hash TablePrefix SumString

Acceptance: 25.1%

#2991Hard

Top Three Wineries

Database

Acceptance: 55.8%

#2994Hard

Friday Purchases II

Database

Acceptance: 74.6%

#2995Hard

Viewers Turned Streamers

Database

Acceptance: 43.4%

#2999Hard

Count the Number of Powerful Integers

Dynamic ProgrammingMathString

Acceptance: 46.3%

#3003Hard

Maximize the Number of Partitions After Operations

Bit ManipulationBitmaskDynamic Programming+1

Acceptance: 53.5%

#3008Hard

Find Beautiful Indices in the Given Array II

Binary SearchHash FunctionRolling Hash+3

Acceptance: 28.3%

#3009Hard

Maximum Number of Intersections on the Chart

ArrayBinary Indexed TreeGeometry+1

Acceptance: 45.5%

#3013Hard

Divide an Array Into Subarrays With Minimum Cost II

ArrayHash TableHeap (Priority Queue)+1

Acceptance: 54.7%

#3017Hard

Count the Number of Houses at a Certain Distance II

GraphPrefix Sum

Acceptance: 23.7%

#3018Hard

Maximum Number of Removal Queries That Can Be Processed I

ArrayDynamic Programming

Acceptance: 44.8%

#3022Hard

Minimize OR of Remaining Elements Using Operations

ArrayBit ManipulationGreedy

Acceptance: 29.6%

#3027Hard

Find the Number of Ways to Place People II

ArrayEnumerationGeometry+2

Acceptance: 64.4%

#3031Hard

Minimum Time to Revert Word to Initial State II

Hash FunctionRolling HashString+1

Acceptance: 35.1%

#3036Hard

Number of Subarrays That Match a Pattern II

ArrayHash FunctionRolling Hash+1

Acceptance: 34.1%

#3037Hard

Find Pattern in Infinite Stream II

ArrayHash FunctionRolling Hash+2

Acceptance: 67.5%

#3041Hard

Maximize Consecutive Elements in an Array After Modification

ArrayDynamic ProgrammingSorting

Acceptance: 33.7%

#3045Hard

Count Prefix and Suffix Pairs II

ArrayHash FunctionRolling Hash+3

Acceptance: 28.2%

#3049Hard

Earliest Second to Mark Indices II

ArrayBinary SearchGreedy+1

Acceptance: 22.6%

#3052Hard

Maximize Items

Database

Acceptance: 72.0%

#3057Hard

Employees Project Allocation

Database

Acceptance: 68.4%

#3060Hard

User Activities within Time Bounds

Database

Acceptance: 40.6%

#3061Hard

Calculate Trapping Rain Water

Database

Acceptance: 81.1%

#3068Hard

Find the Maximum Sum of Node Values

ArrayBit ManipulationDynamic Programming+3

Acceptance: 69.5%

#3072Hard

Distribute Elements Into Two Arrays II

ArrayBinary Indexed TreeSegment Tree+1

Acceptance: 32.1%

#3077Hard

Maximum Strength of K Disjoint Subarrays

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 28.2%

#3082Hard

Find the Sum of the Power of All Subsequences

ArrayDynamic Programming

Acceptance: 38.1%

#3086Hard

Minimum Moves to Pick K Ones

ArrayGreedyPrefix Sum+1

Acceptance: 21.6%

#3088Hard

Make String Anti-palindrome

Counting SortGreedySorting+1

Acceptance: 46.6%

#3093Hard

Longest Common Suffix Queries

ArrayStringTrie

Acceptance: 52.8%

#3098Hard

Find the Sum of Subsequence Powers

ArrayDynamic ProgrammingSorting

Acceptance: 25.1%

#3102Hard

Minimize Manhattan Distances

ArrayGeometryMath+2

Acceptance: 32.9%

#3103Hard

Find Trending Hashtags II

Database

Acceptance: 64.7%

#3104Hard

Find Longest Self-Contained Substring

Binary SearchHash TablePrefix Sum+1

Acceptance: 58.6%

#3108Hard

Minimum Cost Walk in Weighted Graph

ArrayBit ManipulationGraph+1

Acceptance: 68.3%

#3113Hard

Find the Number of Subarrays Where Boundary Elements Are Maximum

ArrayBinary SearchMonotonic Stack+1

Acceptance: 34.2%

#3116Hard

Kth Smallest Amount With Single Denomination Combination

ArrayBinary SearchBit Manipulation+3

Acceptance: 50.3%

#3117Hard

Minimum Sum of Values by Dividing Array

ArrayBinary SearchBit Manipulation+3

Acceptance: 27.9%

#3123Hard

Find Edges in Shortest Paths

Breadth-First SearchDepth-First SearchGraph+2

Acceptance: 47.0%

#3130Hard

Find All Possible Stable Binary Arrays II

Dynamic ProgrammingPrefix Sum

Acceptance: 58.4%

#3134Hard

Find the Median of the Uniqueness Array

ArrayBinary SearchHash Table+1

Acceptance: 30.0%

#3139Hard

Minimum Cost to Equalize Array

ArrayEnumerationGreedy

Acceptance: 18.8%

#3141Hard

Maximum Hamming Distances

ArrayBit ManipulationBreadth-First Search

Acceptance: 50.0%

#3145Hard

Find Products of Elements of Big Array

ArrayBinary SearchBit Manipulation

Acceptance: 24.4%

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