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
3425. Longest Special Path	Hard	23.2%	Array Depth-First Search+3	Read
3405. Count the Number of Arrays with K Matching Adjacent Elements	Hard	58.3%	Combinatorics Math	Read
3378. Count Connected Components in LCM Graph	Hard	30.7%	Array Hash Table+3	Read
3420. Count Non-Decreasing Subarrays After K Operations	Hard	25.0%	Array Monotonic Queue+5	Read
3389. Minimum Operations to Make Character Frequencies Equal	Hard	25.8%	Counting Dynamic Programming+3	Read
3414. Maximum Score of Non-overlapping Intervals	Hard	65.9%	Array Binary Search+2	Read
3888. Minimum Operations to Make All Grid Elements Equal	Hard	61.3%		Read
3883. Count Non Decreasing Arrays With Given Digit Sums	Hard	40.3%	Array Dynamic Programming+1	Read
3886. Sum of Sortable Integers	Hard	31.8%	Array Enumeration+2	Read
3887. Incremental Even-Weighted Cycle Queries	Hard	49.1%	Graph Union Find	Read
3892. Minimum Operations to Achieve At Least K Peaks	Hard	30.6%	Array Dynamic Programming	Read
3897. Maximum Value of Concatenated Binary Segments	Hard	26.7%	Array Greedy+1	Read
3901. Good Subsequence Queries	Hard	20.6%	Array Math+2	Read
3906. Count Good Integers on a Grid Path	Hard	49.6%	Dynamic Programming	Read
3911. K-th Smallest Remaining Even Integer in Subarray Queries	Hard	28.6%	Array Binary Search	Read
3910. Count Connected Subgraphs with Even Node Sum	Hard	59.0%	Array Bit Manipulation+5	Read
3915. Maximum Sum of Alternating Subsequence With Distance at Least K	Hard	30.7%	Array Dynamic Programming+1	Read
3916. Number of ZigZag Arrays III	Hard	62.9%		Read
3920. Maximize Fixed Points After Deletions	Hard	19.9%	Array Binary Search+1	Read
3924. Minimum Threshold Path With Limited Heavy Edges	Hard	39.0%	Binary Search Breadth-First Search+1	Read
3928. Minimum Cost to Buy Apples II	Hard	31.8%	Array Graph+2	Read
3929. Minimum Partition Score II	Hard	44.8%		Read
3930. Power Update After K-th Largest Insertion II	Hard	81.3%		Read
3934. Smallest Unique Subarray	Hard	39.7%	Array Binary Search+4	Read
3943. Number of Pairs After Increment	Hard	20.9%	Array Counting+2	Read
3939. Count Non Adjacent Subsets in a Rooted Tree	Hard	51.7%	Array Depth-First Search+2	Read
3944. Minimum Operations to Make Array Modulo Alternating II	Hard	64.5%		Read
3948. Lexicographically Maximum MEX Array	Hard	53.6%	Array Greedy+2	Read
3949. Subtree Inversion Sum II	Hard	68.9%		Read
3953. Maximum Score with Co-Prime Element	Hard	27.5%	Array Combinatorics+4	Read
3957. Maximum Sum of M Non-Overlapping Subarrays II	Hard	16.6%	Array Binary Search+5	Read
3956. Maximum Sum of M Non-Overlapping Subarrays I	Hard	26.3%	Array Binary Search+5	Read
3962. Maximum Subarray Sum After at Most K Swaps	Hard	14.2%	Array Binary Indexed Tree+5	Read
3972. Valid Subarrays With Matching Sum Digits II	Hard	35.9%		Read
3966. Count Good Integers in a Range	Hard	49.8%	Dynamic Programming Math	Read
3971. Maximum Total Value	Hard	29.7%	Array Binary Search+2	Read
3967. Finish Time of Tasks II	Hard	24.8%		Read
3973. Distinct Gate Paths to LCA	Hard	57.9%		Read
3977. Minimum Time to Reach Target With Limited Power	Hard	40.4%	Array Dynamic Programming+3	Read
3990. Create Grid With Exactly K Paths II	Hard	73.8%		Read
3989. Maximum Consistent Columns in a Grid	Hard	68.7%	Array Dynamic Programming+1	Read
3995. Minimum Cost to Convert String III	Hard	55.6%	Array Dynamic Programming+1	Read
3981. Count Distinct Ways to Form Target from Two Strings	Hard	46.4%	Dynamic Programming Prefix Sum+1	Read
3985. Palindromic Subarray Sum	Hard	34.0%	Array Binary Search+2	Read
3999. Minimum Number of String Groups Through Transformations	Hard	47.9%	Hash Table String+1	Read
4003. Minimum Cost Path with Alternating Directions III	Hard	61.4%	Array Graph+3	Read
4005. Minimum Operations to Make Array Equal III	Hard	26.3%		Read
4004. Minimum Moves to Balance Circular Array II	Hard	61.8%		Read
4007. Widest Possible Fence	Hard	16.9%	Array Counting+2	Read
4009. Minimum Possible Maximum Waiting Time	Hard	29.3%	Array Dynamic Programming+1	Read

#3425Hard

Longest Special Path

ArrayDepth-First SearchHash Table+2

Acceptance: 23.2%

#3405Hard

Count the Number of Arrays with K Matching Adjacent Elements

CombinatoricsMath

Acceptance: 58.3%

#3378Hard

Count Connected Components in LCM Graph

ArrayHash TableMath+2

Acceptance: 30.7%

#3420Hard

Count Non-Decreasing Subarrays After K Operations

ArrayMonotonic QueueMonotonic Stack+4

Acceptance: 25.0%

#3389Hard

Minimum Operations to Make Character Frequencies Equal

CountingDynamic ProgrammingEnumeration+2

Acceptance: 25.8%

#3414Hard

Maximum Score of Non-overlapping Intervals

ArrayBinary SearchDynamic Programming+1

Acceptance: 65.9%

#3888Hard

Minimum Operations to Make All Grid Elements Equal

Acceptance: 61.3%

#3883Hard

Count Non Decreasing Arrays With Given Digit Sums

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 40.3%

#3886Hard

Sum of Sortable Integers

ArrayEnumerationMath+1

Acceptance: 31.8%

#3887Hard

Incremental Even-Weighted Cycle Queries

GraphUnion Find

Acceptance: 49.1%

#3892Hard

Minimum Operations to Achieve At Least K Peaks

ArrayDynamic Programming

Acceptance: 30.6%

#3897Hard

Maximum Value of Concatenated Binary Segments

ArrayGreedySorting

Acceptance: 26.7%

#3901Hard

Good Subsequence Queries

ArrayMathNumber Theory+1

Acceptance: 20.6%

#3906Hard

Count Good Integers on a Grid Path

Dynamic Programming

Acceptance: 49.6%

#3911Hard

K-th Smallest Remaining Even Integer in Subarray Queries

ArrayBinary Search

Acceptance: 28.6%

#3910Hard

Count Connected Subgraphs with Even Node Sum

ArrayBit ManipulationBreadth-First Search+4

Acceptance: 59.0%

#3915Hard

Maximum Sum of Alternating Subsequence With Distance at Least K

ArrayDynamic ProgrammingSegment Tree

Acceptance: 30.7%

#3916Hard

Number of ZigZag Arrays III

Acceptance: 62.9%

#3920Hard

Maximize Fixed Points After Deletions

ArrayBinary SearchSorting

Acceptance: 19.9%

#3924Hard

Minimum Threshold Path With Limited Heavy Edges

Binary SearchBreadth-First SearchGraph

Acceptance: 39.0%

#3928Hard

Minimum Cost to Buy Apples II

ArrayGraphHeap (Priority Queue)+1

Acceptance: 31.8%

#3929Hard

Minimum Partition Score II

Acceptance: 44.8%

#3930Hard

Power Update After K-th Largest Insertion II

Acceptance: 81.3%

#3934Hard

Smallest Unique Subarray

ArrayBinary SearchHash Function+3

Acceptance: 39.7%

#3943Hard

Number of Pairs After Increment

ArrayCountingDivide and Conquer+1

Acceptance: 20.9%

#3939Hard

Count Non Adjacent Subsets in a Rooted Tree

ArrayDepth-First SearchDynamic Programming+1

Acceptance: 51.7%

#3944Hard

Minimum Operations to Make Array Modulo Alternating II

Acceptance: 64.5%

#3948Hard

Lexicographically Maximum MEX Array

ArrayGreedyHash Table+1

Acceptance: 53.6%

#3949Hard

Subtree Inversion Sum II

Acceptance: 68.9%

#3953Hard

Maximum Score with Co-Prime Element

ArrayCombinatoricsEnumeration+3

Acceptance: 27.5%

#3957Hard

Maximum Sum of M Non-Overlapping Subarrays II

ArrayBinary SearchDynamic Programming+4

Acceptance: 16.6%

#3956Hard

Maximum Sum of M Non-Overlapping Subarrays I

ArrayBinary SearchDynamic Programming+4

Acceptance: 26.3%

#3962Hard

Maximum Subarray Sum After at Most K Swaps

ArrayBinary Indexed TreeGreedy+4

Acceptance: 14.2%

#3972Hard

Valid Subarrays With Matching Sum Digits II

Acceptance: 35.9%

#3966Hard

Count Good Integers in a Range

Dynamic ProgrammingMath

Acceptance: 49.8%

#3971Hard

Maximum Total Value

ArrayBinary SearchGreedy+1

Acceptance: 29.7%

#3967Hard

Finish Time of Tasks II

Acceptance: 24.8%

#3973Hard

Distinct Gate Paths to LCA

Acceptance: 57.9%

#3977Hard

Minimum Time to Reach Target With Limited Power

ArrayDynamic ProgrammingGraph+2

Acceptance: 40.4%

#3990Hard

Create Grid With Exactly K Paths II

Acceptance: 73.8%

#3989Hard

Maximum Consistent Columns in a Grid

ArrayDynamic ProgrammingMatrix

Acceptance: 68.7%

#3995Hard

Minimum Cost to Convert String III

ArrayDynamic ProgrammingString

Acceptance: 55.6%

#3981Hard

Count Distinct Ways to Form Target from Two Strings

Dynamic ProgrammingPrefix SumString

Acceptance: 46.4%

#3985Hard

Palindromic Subarray Sum

ArrayBinary SearchHash Function+1

Acceptance: 34.0%

#3999Hard

Minimum Number of String Groups Through Transformations

Hash TableStringTwo Pointers

Acceptance: 47.9%

#4003Hard

Minimum Cost Path with Alternating Directions III

ArrayGraphHeap (Priority Queue)+2

Acceptance: 61.4%

#4005Hard

Minimum Operations to Make Array Equal III

Acceptance: 26.3%

#4004Hard

Minimum Moves to Balance Circular Array II

Acceptance: 61.8%

#4007Hard

Widest Possible Fence

ArrayCountingEnumeration+1

Acceptance: 16.9%

#4009Hard

Minimum Possible Maximum Waiting Time

ArrayDynamic ProgrammingMemoization

Acceptance: 29.3%

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