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
3662. Filter Characters by Frequency	Easy	86.2%	Counting Hash Table+1	Read
3698. Split Array With Minimum Difference	Medium	33.6%	Array Prefix Sum	Read
3853. Merge Close Characters	Medium	54.8%	Hash Table String	Read
3683. Earliest Time to Finish One Task	Easy	84.5%	Array	Read
3678. Smallest Absent Positive Greater Than Average	Easy	34.2%	Array Hash Table	Read
3695. Maximize Alternating Sum Using Swaps	Hard	62.5%	Array Greedy+2	Read
3688. Bitwise OR of Even Numbers in an Array	Easy	84.9%	Array Bit Manipulation+1	Read
3668. Restore Finishing Order	Easy	91.1%	Array Hash Table	Read
3691. Maximum Total Subarray Value II	Hard	41.6%	Array Greedy+2	Read
3656. Determine if a Simple Graph Exists	Medium	47.5%	Array Binary Search+3	Read
3689. Maximum Total Subarray Value I	Medium	71.9%	Array Greedy	Read
3708. Longest Fibonacci Subarray	Medium	68.5%	Array	Read
3859. Count Subarrays With K Distinct Integers	Hard	21.0%	Array Counting+2	Read
3676. Count Bowl Subarrays	Medium	48.7%	Array Monotonic Stack+1	Read
3675. Minimum Operations to Transform String	Medium	61.9%	Greedy String	Read
3674. Minimum Operations to Equalize Array	Easy	60.8%	Array Bit Manipulation+1	Read
3684. Maximize Sum of At Most K Distinct Elements	Easy	76.8%	Array Greedy+2	Read
3658. GCD of Odd and Even Sums	Easy	89.8%	Math Number Theory	Read
3663. Find The Least Frequent Digit	Easy	68.8%	Array Counting+2	Read
3641. Longest Semi-Repeating Subarray	Medium	63.9%	Array Hash Table+1	Read
3680. Generate Schedule	Medium	25.3%	Array Greedy+1	Read
3681. Maximum XOR of Subsequences	Hard	49.5%	Array Bit Manipulation+2	Read
3671. Sum of Beautiful Subsequences	Hard	31.5%	Array Binary Indexed Tree+2	Read
3647. Maximum Weight in Two Bags	Medium	58.3%	Array Dynamic Programming	Read
3742. Maximum Path Score in a Grid	Medium	53.7%	Array Dynamic Programming+1	Read
3666. Minimum Operations to Equalize Binary String	Hard	45.2%	Breadth-First Search Math+3	Read
3661. Maximum Walls Destroyed by Robots	Hard	48.0%	Array Binary Search+2	Read
3660. Jump Game IX	Medium	46.1%	Array Dynamic Programming	Read
3652. Best Time to Buy and Sell Stock using Strategy	Medium	59.8%	Array Prefix Sum+1	Read
3659. Partition Array Into K-Distinct Groups	Medium	47.1%	Array Counting+1	Read
3655. XOR After Range Multiplication Queries II	Hard	47.8%	Array Divide and Conquer	Read
3653. XOR After Range Multiplication Queries I	Medium	73.3%	Array Divide and Conquer+1	Read
3643. Flip Square Submatrix Vertically	Easy	79.3%	Array Matrix+1	Read
3631. Sort Threats by Severity and Exploitability	Medium	63.3%	Array Sorting	Read
3635. Earliest Finish Time for Land and Water Rides II	Medium	64.2%	Array Binary Search+3	Read
3654. Minimum Sum After Divisible Sum Deletions	Medium	45.9%	Array Dynamic Programming+2	Read
3633. Earliest Finish Time for Land and Water Rides I	Easy	73.0%	Array Binary Search+3	Read
3700. Number of ZigZag Arrays II	Hard	67.7%	Dynamic Programming Math	Read
3649. Number of Perfect Pairs	Medium	34.2%	Array Math+2	Read
3699. Number of ZigZag Arrays I	Hard	50.2%	Dynamic Programming Prefix Sum	Read
3616. Number of Student Replacements	Medium	86.0%	Array Simulation	Read
3645. Maximum Total from Optimal Activation Order	Medium	33.1%	Array Greedy+3	Read
3634. Minimum Removals to Balance Array	Medium	47.9%	Array Binary Search+2	Read
3715. Sum of Perfect Square Ancestors	Hard	41.3%	Array Counting+5	Read
3640. Trionic Array II	Hard	47.3%	Array Dynamic Programming	Read
3636. Threshold Majority Queries	Hard	22.5%	Array Binary Search+4	Read
3638. Maximum Balanced Shipments	Medium	61.4%	Array Dynamic Programming+3	Read
3679. Minimum Discards to Balance Inventory	Medium	34.9%	Array Counting+3	Read
3637. Trionic Array I	Easy	49.5%	Array	Read
3646. Next Special Palindrome Number	Hard	28.0%	Backtracking Bit Manipulation	Read

#3662Easy

Filter Characters by Frequency

CountingHash TableString

Acceptance: 86.2%

#3698Medium

Split Array With Minimum Difference

ArrayPrefix Sum

Acceptance: 33.6%

#3853Medium

Merge Close Characters

Hash TableString

Acceptance: 54.8%

#3683Easy

Earliest Time to Finish One Task

Array

Acceptance: 84.5%

#3678Easy

Smallest Absent Positive Greater Than Average

ArrayHash Table

Acceptance: 34.2%

#3695Hard

Maximize Alternating Sum Using Swaps

ArrayGreedySorting+1

Acceptance: 62.5%

#3688Easy

Bitwise OR of Even Numbers in an Array

ArrayBit ManipulationSimulation

Acceptance: 84.9%

#3668Easy

Restore Finishing Order

ArrayHash Table

Acceptance: 91.1%

#3691Hard

Maximum Total Subarray Value II

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 41.6%

#3656Medium

Determine if a Simple Graph Exists

ArrayBinary SearchGraph+2

Acceptance: 47.5%

#3689Medium

Maximum Total Subarray Value I

ArrayGreedy

Acceptance: 71.9%

#3708Medium

Longest Fibonacci Subarray

Array

Acceptance: 68.5%

#3859Hard

Count Subarrays With K Distinct Integers

ArrayCountingHash Table+1

Acceptance: 21.0%

#3676Medium

Count Bowl Subarrays

ArrayMonotonic StackStack

Acceptance: 48.7%

#3675Medium

Minimum Operations to Transform String

GreedyString

Acceptance: 61.9%

#3674Easy

Minimum Operations to Equalize Array

ArrayBit ManipulationBrainteaser

Acceptance: 60.8%

#3684Easy

Maximize Sum of At Most K Distinct Elements

ArrayGreedyHash Table+1

Acceptance: 76.8%

#3658Easy

GCD of Odd and Even Sums

MathNumber Theory

Acceptance: 89.8%

#3663Easy

Find The Least Frequent Digit

ArrayCountingHash Table+1

Acceptance: 68.8%

#3641Medium

Longest Semi-Repeating Subarray

ArrayHash TableSliding Window

Acceptance: 63.9%

#3680Medium

Generate Schedule

ArrayGreedyMath

Acceptance: 25.3%

#3681Hard

Maximum XOR of Subsequences

ArrayBit ManipulationGreedy+1

Acceptance: 49.5%

#3671Hard

Sum of Beautiful Subsequences

ArrayBinary Indexed TreeMath+1

Acceptance: 31.5%

#3647Medium

Maximum Weight in Two Bags

ArrayDynamic Programming

Acceptance: 58.3%

#3742Medium

Maximum Path Score in a Grid

ArrayDynamic ProgrammingMatrix

Acceptance: 53.7%

#3666Hard

Minimum Operations to Equalize Binary String

Breadth-First SearchMathOrdered Set+2

Acceptance: 45.2%

#3661Hard

Maximum Walls Destroyed by Robots

ArrayBinary SearchDynamic Programming+1

Acceptance: 48.0%

#3660Medium

Jump Game IX

ArrayDynamic Programming

Acceptance: 46.1%

#3652Medium

Best Time to Buy and Sell Stock using Strategy

ArrayPrefix SumSliding Window

Acceptance: 59.8%

#3659Medium

Partition Array Into K-Distinct Groups

ArrayCountingHash Table

Acceptance: 47.1%

#3655Hard

XOR After Range Multiplication Queries II

ArrayDivide and Conquer

Acceptance: 47.8%

#3653Medium

XOR After Range Multiplication Queries I

ArrayDivide and ConquerSimulation

Acceptance: 73.3%

#3643Easy

Flip Square Submatrix Vertically

ArrayMatrixTwo Pointers

Acceptance: 79.3%

#3631Medium

Sort Threats by Severity and Exploitability

ArraySorting

Acceptance: 63.3%

#3635Medium

Earliest Finish Time for Land and Water Rides II

ArrayBinary SearchGreedy+2

Acceptance: 64.2%

#3654Medium

Minimum Sum After Divisible Sum Deletions

ArrayDynamic ProgrammingHash Table+1

Acceptance: 45.9%

#3633Easy

Earliest Finish Time for Land and Water Rides I

ArrayBinary SearchGreedy+2

Acceptance: 73.0%

#3700Hard

Number of ZigZag Arrays II

Dynamic ProgrammingMath

Acceptance: 67.7%

#3649Medium

Number of Perfect Pairs

ArrayMathSorting+1

Acceptance: 34.2%

#3699Hard

Number of ZigZag Arrays I

Dynamic ProgrammingPrefix Sum

Acceptance: 50.2%

#3616Medium

Number of Student Replacements

ArraySimulation

Acceptance: 86.0%

#3645Medium

Maximum Total from Optimal Activation Order

ArrayGreedyHeap (Priority Queue)+2

Acceptance: 33.1%

#3634Medium

Minimum Removals to Balance Array

ArrayBinary SearchSliding Window+1

Acceptance: 47.9%

#3715Hard

Sum of Perfect Square Ancestors

ArrayCountingDepth-First Search+4

Acceptance: 41.3%

#3640Hard

Trionic Array II

ArrayDynamic Programming

Acceptance: 47.3%

#3636Hard

Threshold Majority Queries

ArrayBinary SearchCounting+3

Acceptance: 22.5%

#3638Medium

Maximum Balanced Shipments

ArrayDynamic ProgrammingGreedy+2

Acceptance: 61.4%

#3679Medium

Minimum Discards to Balance Inventory

ArrayCountingHash Table+2

Acceptance: 34.9%

#3637Easy

Trionic Array I

Array

Acceptance: 49.5%

#3646Hard

Next Special Palindrome Number

BacktrackingBit Manipulation

Acceptance: 28.0%

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