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
3931. Check Adjacent Digit Differences	Easy	77.1%	String	Read
3932. Count K-th Roots in a Range	Medium	24.6%	Binary Search Math	Read
3934. Smallest Unique Subarray	Hard	39.7%	Array Binary Search+4	Read
3935. Power Update After K-th Largest Insertion I	Medium	68.1%		Read
3933. Largest Local Values in a Matrix II	Medium	18.5%	Array Matrix+1	Read
3936. Minimum Swaps to Move Zeros to End	Easy	59.7%	Array Two Pointers	Read
3941. Password Strength	Medium	74.5%	Hash Table String	Read
3940. Limit Occurrences in Sorted Array	Easy	72.6%	Array Two Pointers	Read
3937. Minimum Operations to Make Array Modulo Alternating I	Medium	46.5%	Array Enumeration	Read
3942. Minimum Operations to Sort a Permutation	Medium	27.8%	Array	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
3938. Maximum Path Intersection Sum in a Grid	Medium	25.6%	Array Dynamic Programming+2	Read
3945. Digit Frequency Score	Easy	90.7%	Hash Table Math	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
3947. Maximum Number of Items From Sale II	Medium	30.2%	Array Greedy+2	Read
3946. Maximum Number of Items From Sale I	Medium	37.3%	Array Dynamic Programming+1	Read
3949. Subtree Inversion Sum II	Hard	68.9%		Read
3954. Sum of Compatible Numbers in Range I	Easy	58.4%	Bit Manipulation Dynamic Programming+1	Read
3950. Exactly One Consecutive Set Bits Pair	Easy	50.4%	Bit Manipulation	Read
3951. Minimum Energy to Maintain Brightness	Medium	53.4%	Array Sorting	Read
3955. Valid Binary Strings With Cost Limit	Medium	78.5%	Backtracking Bit Manipulation+2	Read
3953. Maximum Score with Co-Prime Element	Hard	27.5%	Array Combinatorics+4	Read
3952. Maximum Total Value of Covered Indices	Medium	28.5%	Array Dynamic Programming+2	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
3958. Minimum Cost to Split into Ones II	Medium	68.4%		Read
3959. Check Good Integer	Easy	82.6%	Math Simulation	Read
3960. Frequency Balance Subarray	Medium	29.5%	Array Counting+1	Read
3962. Maximum Subarray Sum After at Most K Swaps	Hard	14.2%	Array Binary Indexed Tree+5	Read
3961. Maximize Sum of Device Ratings	Medium	39.4%	Array Greedy+2	Read
3963. Create Grid With Exactly One Path	Easy	75.9%		Read
3968. Maximum Manhattan Distance After All Moves	Medium	63.3%	Counting Math+1	Read
3964. Minimum Lights to Illuminate a Road	Medium	37.8%	Array Prefix Sum	Read
3972. Valid Subarrays With Matching Sum Digits II	Hard	35.9%		Read
3969. Valid Subarrays With Matching Sum Digits I	Medium	46.8%	Array Enumeration+3	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
3970. Shortest Path With At Most K Consecutive Identical Characters	Medium	44.7%	Graph Heap (Priority Queue)+2	Read
3967. Finish Time of Tasks II	Hard	24.8%		Read
3965. Finish Time of Tasks I	Medium	60.3%	Array Depth-First Search+2	Read
3973. Distinct Gate Paths to LCA	Hard	57.9%		Read
3974. Maximum Total Sum of K Selected Elements	Medium	49.1%	Array Greedy+1	Read
3977. Minimum Time to Reach Target With Limited Power	Hard	40.4%	Array Dynamic Programming+3	Read
3976. Maximum Subarray Sum After Multiplier	Medium	25.9%	Array Dynamic Programming	Read
3975. Filter Occupied Intervals	Medium	46.0%	Array Sorting	Read
3996. Even Number of Knight Moves	Easy	74.5%	Array Math	Read
3993. Maximum Value of an Alternating Sequence	Medium	31.5%	Greedy Math	Read
3997. Count Dominant Nodes in a Binary Tree	Medium	72.1%	Binary Tree Depth-First Search+1	Read

#3931Easy

Check Adjacent Digit Differences

String

Acceptance: 77.1%

#3932Medium

Count K-th Roots in a Range

Binary SearchMath

Acceptance: 24.6%

#3934Hard

Smallest Unique Subarray

ArrayBinary SearchHash Function+3

Acceptance: 39.7%

#3935Medium

Power Update After K-th Largest Insertion I

Acceptance: 68.1%

#3933Medium

Largest Local Values in a Matrix II

ArrayMatrixPrefix Sum

Acceptance: 18.5%

#3936Easy

Minimum Swaps to Move Zeros to End

ArrayTwo Pointers

Acceptance: 59.7%

#3941Medium

Password Strength

Hash TableString

Acceptance: 74.5%

#3940Easy

Limit Occurrences in Sorted Array

ArrayTwo Pointers

Acceptance: 72.6%

#3937Medium

Minimum Operations to Make Array Modulo Alternating I

ArrayEnumeration

Acceptance: 46.5%

#3942Medium

Minimum Operations to Sort a Permutation

Array

Acceptance: 27.8%

#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%

#3938Medium

Maximum Path Intersection Sum in a Grid

ArrayDynamic ProgrammingMatrix+1

Acceptance: 25.6%

#3945Easy

Digit Frequency Score

Hash TableMath

Acceptance: 90.7%

#3944Hard

Minimum Operations to Make Array Modulo Alternating II

Acceptance: 64.5%

#3948Hard

Lexicographically Maximum MEX Array

ArrayGreedyHash Table+1

Acceptance: 53.6%

#3947Medium

Maximum Number of Items From Sale II

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 30.2%

#3946Medium

Maximum Number of Items From Sale I

ArrayDynamic ProgrammingGreedy

Acceptance: 37.3%

#3949Hard

Subtree Inversion Sum II

Acceptance: 68.9%

#3954Easy

Sum of Compatible Numbers in Range I

Bit ManipulationDynamic ProgrammingEnumeration

Acceptance: 58.4%

#3950Easy

Exactly One Consecutive Set Bits Pair

Bit Manipulation

Acceptance: 50.4%

#3951Medium

Minimum Energy to Maintain Brightness

ArraySorting

Acceptance: 53.4%

#3955Medium

Valid Binary Strings With Cost Limit

BacktrackingBit ManipulationEnumeration+1

Acceptance: 78.5%

#3953Hard

Maximum Score with Co-Prime Element

ArrayCombinatoricsEnumeration+3

Acceptance: 27.5%

#3952Medium

Maximum Total Value of Covered Indices

ArrayDynamic ProgrammingGreedy+1

Acceptance: 28.5%

#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%

#3958Medium

Minimum Cost to Split into Ones II

Acceptance: 68.4%

#3959Easy

Check Good Integer

MathSimulation

Acceptance: 82.6%

#3960Medium

Frequency Balance Subarray

ArrayCountingHash Table

Acceptance: 29.5%

#3962Hard

Maximum Subarray Sum After at Most K Swaps

ArrayBinary Indexed TreeGreedy+4

Acceptance: 14.2%

#3961Medium

Maximize Sum of Device Ratings

ArrayGreedyMatrix+1

Acceptance: 39.4%

#3963Easy

Create Grid With Exactly One Path

Acceptance: 75.9%

#3968Medium

Maximum Manhattan Distance After All Moves

CountingMathString

Acceptance: 63.3%

#3964Medium

Minimum Lights to Illuminate a Road

ArrayPrefix Sum

Acceptance: 37.8%

#3972Hard

Valid Subarrays With Matching Sum Digits II

Acceptance: 35.9%

#3969Medium

Valid Subarrays With Matching Sum Digits I

ArrayEnumerationHash Table+2

Acceptance: 46.8%

#3966Hard

Count Good Integers in a Range

Dynamic ProgrammingMath

Acceptance: 49.8%

#3971Hard

Maximum Total Value

ArrayBinary SearchGreedy+1

Acceptance: 29.7%

#3970Medium

Shortest Path With At Most K Consecutive Identical Characters

GraphHeap (Priority Queue)Shortest Path+1

Acceptance: 44.7%

#3967Hard

Finish Time of Tasks II

Acceptance: 24.8%

#3965Medium

Finish Time of Tasks I

ArrayDepth-First SearchDynamic Programming+1

Acceptance: 60.3%

#3973Hard

Distinct Gate Paths to LCA

Acceptance: 57.9%

#3974Medium

Maximum Total Sum of K Selected Elements

ArrayGreedySorting

Acceptance: 49.1%

#3977Hard

Minimum Time to Reach Target With Limited Power

ArrayDynamic ProgrammingGraph+2

Acceptance: 40.4%

#3976Medium

Maximum Subarray Sum After Multiplier

ArrayDynamic Programming

Acceptance: 25.9%

#3975Medium

Filter Occupied Intervals

ArraySorting

Acceptance: 46.0%

#3996Easy

Even Number of Knight Moves

ArrayMath

Acceptance: 74.5%

#3993Medium

Maximum Value of an Alternating Sequence

GreedyMath

Acceptance: 31.5%

#3997Medium

Count Dominant Nodes in a Binary Tree

Binary TreeDepth-First SearchTree

Acceptance: 72.1%

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