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
3725. Count Ways to Choose Coprime Integers from Rows	Hard	46.8%	Array Combinatorics+4	Read
3850. Count Sequences to K	Hard	35.6%	Array Dynamic Programming+3	Read
3777. Minimum Deletions to Make Alternating Substring	Hard	43.0%	Segment Tree String	Read
3729. Count Distinct Subarrays Divisible by K in Sorted Array	Hard	27.4%	Array Hash Table+1	Read
3785. Minimum Swaps to Avoid Forbidden Values	Hard	31.0%	Array Counting+2	Read
3704. Count No-Zero Pairs That Sum to N	Hard	15.6%	Dynamic Programming Math	Read
3721. Longest Balanced Subarray II	Hard	33.7%	Array Divide and Conquer+3	Read
3734. Lexicographically Smallest Palindromic Permutation Greater Than Target	Hard	56.0%	Enumeration String+1	Read
3710. Maximum Partition Factor	Hard	31.8%	Array Binary Search+4	Read
3743. Maximize Cyclic Partition Score	Hard	14.5%	Array Dynamic Programming	Read
3686. Number of Stable Subsequences	Hard	60.2%	Array Dynamic Programming	Read
3677. Count Binary Palindromic Numbers	Hard	33.2%	Bit Manipulation Math	Read
3762. Minimum Operations to Equalize Subarrays	Hard	21.3%	Array Binary Search+2	Read
3695. Maximize Alternating Sum Using Swaps	Hard	62.5%	Array Greedy+2	Read
3691. Maximum Total Subarray Value II	Hard	41.6%	Array Greedy+2	Read
3859. Count Subarrays With K Distinct Integers	Hard	21.0%	Array Counting+2	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
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
3655. XOR After Range Multiplication Queries II	Hard	47.8%	Array Divide and Conquer	Read
3700. Number of ZigZag Arrays II	Hard	67.7%	Dynamic Programming Math	Read
3699. Number of ZigZag Arrays I	Hard	50.2%	Dynamic Programming Prefix Sum	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
3646. Next Special Palindrome Number	Hard	28.0%	Backtracking Bit Manipulation	Read
3624. Number of Integers With Popcount-Depth Equal to K II	Hard	58.5%	Array Binary Indexed Tree+2	Read
3614. Process String with Special Operations II	Hard	39.9%	Simulation String	Read
3621. Number of Integers With Popcount-Depth Equal to K I	Hard	23.0%	Bit Manipulation Combinatorics+2	Read
3615. Longest Palindromic Path in Graph	Hard	22.6%	Bit Manipulation Bitmask+3	Read
3632. Subarrays with XOR at Least K	Hard	45.7%	Array Bit Manipulation+2	Read
3609. Minimum Moves to Reach Target in Grid	Hard	15.5%	Math	Read
3605. Minimum Stability Factor of Array	Hard	20.4%	Array Binary Search+4	Read
3620. Network Recovery Pathways	Hard	50.8%	Array Binary Search+5	Read
3590. Kth Smallest Path XOR Sum	Hard	29.5%	Array Depth-First Search+2	Read
3600. Maximize Spanning Tree Stability with Upgrades	Hard	65.9%	Binary Search Graph+3	Read
3585. Find Weighted Median Node in Tree	Hard	26.7%	Array Binary Search+4	Read
3625. Count Number of Trapezoids II	Hard	40.0%	Array Geometry+2	Read
3594. Minimum Time to Transport All Individuals	Hard	28.3%	Array Bit Manipulation+4	Read
3651. Minimum Cost Path with Teleportations	Hard	45.1%	Array Dynamic Programming+1	Read
3574. Maximize Subarray GCD Score	Hard	25.5%	Array Enumeration+2	Read
3549. Multiply Two Polynomials	Hard	58.6%	Array Math	Read
3630. Partition Array for Maximum XOR and AND	Hard	17.6%	Array Bit Manipulation+3	Read
3569. Maximize Count of Distinct Primes After Split	Hard	19.0%	Array Math+2	Read
3575. Maximum Good Subtree Score	Hard	44.0%	Array Bit Manipulation+4	Read
3563. Lexicographically Smallest String After Adjacent Removals	Hard	17.9%	Dynamic Programming String	Read
3579. Minimum Steps to Convert String with Operations	Hard	41.9%	Dynamic Programming String	Read
3526. Range XOR Queries with Subarray Reversals	Hard	62.4%	Array Binary Tree+1	Read
3544. Subtree Inversion Sum	Hard	41.6%	Array Depth-First Search+2	Read

#3725Hard

Count Ways to Choose Coprime Integers from Rows

ArrayCombinatoricsDynamic Programming+3

Acceptance: 46.8%

#3850Hard

Count Sequences to K

ArrayDynamic ProgrammingMath+2

Acceptance: 35.6%

#3777Hard

Minimum Deletions to Make Alternating Substring

Segment TreeString

Acceptance: 43.0%

#3729Hard

Count Distinct Subarrays Divisible by K in Sorted Array

ArrayHash TablePrefix Sum

Acceptance: 27.4%

#3785Hard

Minimum Swaps to Avoid Forbidden Values

ArrayCountingGreedy+1

Acceptance: 31.0%

#3704Hard

Count No-Zero Pairs That Sum to N

Dynamic ProgrammingMath

Acceptance: 15.6%

#3721Hard

Longest Balanced Subarray II

ArrayDivide and ConquerHash Table+2

Acceptance: 33.7%

#3734Hard

Lexicographically Smallest Palindromic Permutation Greater Than Target

EnumerationStringTwo Pointers

Acceptance: 56.0%

#3710Hard

Maximum Partition Factor

ArrayBinary SearchBreadth-First Search+3

Acceptance: 31.8%

#3743Hard

Maximize Cyclic Partition Score

ArrayDynamic Programming

Acceptance: 14.5%

#3686Hard

Number of Stable Subsequences

ArrayDynamic Programming

Acceptance: 60.2%

#3677Hard

Count Binary Palindromic Numbers

Bit ManipulationMath

Acceptance: 33.2%

#3762Hard

Minimum Operations to Equalize Subarrays

ArrayBinary SearchMath+1

Acceptance: 21.3%

#3695Hard

Maximize Alternating Sum Using Swaps

ArrayGreedySorting+1

Acceptance: 62.5%

#3691Hard

Maximum Total Subarray Value II

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 41.6%

#3859Hard

Count Subarrays With K Distinct Integers

ArrayCountingHash Table+1

Acceptance: 21.0%

#3681Hard

Maximum XOR of Subsequences

ArrayBit ManipulationGreedy+1

Acceptance: 49.5%

#3671Hard

Sum of Beautiful Subsequences

ArrayBinary Indexed TreeMath+1

Acceptance: 31.5%

#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%

#3655Hard

XOR After Range Multiplication Queries II

ArrayDivide and Conquer

Acceptance: 47.8%

#3700Hard

Number of ZigZag Arrays II

Dynamic ProgrammingMath

Acceptance: 67.7%

#3699Hard

Number of ZigZag Arrays I

Dynamic ProgrammingPrefix Sum

Acceptance: 50.2%

#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%

#3646Hard

Next Special Palindrome Number

BacktrackingBit Manipulation

Acceptance: 28.0%

#3624Hard

Number of Integers With Popcount-Depth Equal to K II

ArrayBinary Indexed TreeDivide and Conquer+1

Acceptance: 58.5%

#3614Hard

Process String with Special Operations II

SimulationString

Acceptance: 39.9%

#3621Hard

Number of Integers With Popcount-Depth Equal to K I

Bit ManipulationCombinatoricsDynamic Programming+1

Acceptance: 23.0%

#3615Hard

Longest Palindromic Path in Graph

Bit ManipulationBitmaskDynamic Programming+2

Acceptance: 22.6%

#3632Hard

Subarrays with XOR at Least K

ArrayBit ManipulationPrefix Sum+1

Acceptance: 45.7%

#3609Hard

Minimum Moves to Reach Target in Grid

Math

Acceptance: 15.5%

#3605Hard

Minimum Stability Factor of Array

ArrayBinary SearchGreedy+3

Acceptance: 20.4%

#3620Hard

Network Recovery Pathways

ArrayBinary SearchDynamic Programming+4

Acceptance: 50.8%

#3590Hard

Kth Smallest Path XOR Sum

ArrayDepth-First SearchOrdered Set+1

Acceptance: 29.5%

#3600Hard

Maximize Spanning Tree Stability with Upgrades

Binary SearchGraphGreedy+2

Acceptance: 65.9%

#3585Hard

Find Weighted Median Node in Tree

ArrayBinary SearchBit Manipulation+3

Acceptance: 26.7%

#3625Hard

Count Number of Trapezoids II

ArrayGeometryHash Table+1

Acceptance: 40.0%

#3594Hard

Minimum Time to Transport All Individuals

ArrayBit ManipulationBitmask+3

Acceptance: 28.3%

#3651Hard

Minimum Cost Path with Teleportations

ArrayDynamic ProgrammingMatrix

Acceptance: 45.1%

#3574Hard

Maximize Subarray GCD Score

ArrayEnumerationMath+1

Acceptance: 25.5%

#3549Hard

Multiply Two Polynomials

ArrayMath

Acceptance: 58.6%

#3630Hard

Partition Array for Maximum XOR and AND

ArrayBit ManipulationEnumeration+2

Acceptance: 17.6%

#3569Hard

Maximize Count of Distinct Primes After Split

ArrayMathNumber Theory+1

Acceptance: 19.0%

#3575Hard

Maximum Good Subtree Score

ArrayBit ManipulationBitmask+3

Acceptance: 44.0%

#3563Hard

Lexicographically Smallest String After Adjacent Removals

Dynamic ProgrammingString

Acceptance: 17.9%

#3579Hard

Minimum Steps to Convert String with Operations

Dynamic ProgrammingString

Acceptance: 41.9%

#3526Hard

Range XOR Queries with Subarray Reversals

ArrayBinary TreeTree

Acceptance: 62.4%

#3544Hard

Subtree Inversion Sum

ArrayDepth-First SearchDynamic Programming+1

Acceptance: 41.6%

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