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
3752. Lexicographically Smallest Negated Permutation that Sums to Target	Medium	31.5%	Array Greedy+3	Read
3739. Count Subarrays With Majority Element II	Hard	65.2%	Array Divide and Conquer+4	Read
3737. Count Subarrays With Majority Element I	Medium	75.7%	Array Counting+5	Read
3722. Lexicographically Smallest String After Reverse	Medium	53.9%	Binary Search Enumeration+1	Read
3786. Total Sum of Interaction Cost in Tree Groups	Hard	54.3%	Array Depth-First Search+1	Read
3799. Word Squares II	Medium	53.8%	Array Backtracking+3	Read
3706. Maximum Distance Between Unequal Words in Array II	Medium	71.5%	Array String	Read
3725. Count Ways to Choose Coprime Integers from Rows	Hard	46.8%	Array Combinatorics+4	Read
3712. Sum of Elements With Frequency Divisible by K	Easy	77.7%	Array Counting+1	Read
3815. Design Auction System	Medium	41.9%	Design Hash Table+2	Read
3696. Maximum Distance Between Unequal Words in Array I	Easy	81.7%	Array String	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
3840. House Robber V	Medium	53.3%	Array Dynamic Programming	Read
3785. Minimum Swaps to Avoid Forbidden Values	Hard	31.0%	Array Counting+2	Read
3687. Library Late Fee Calculator	Easy	94.4%	Array Simulation	Read
3709. Design Exam Scores Tracker	Medium	44.0%	Array Binary Search+2	Read
3701. Compute Alternating Sum	Easy	89.8%	Array Simulation	Read
3751. Total Waviness of Numbers in Range I	Medium	86.9%	Dynamic Programming Enumeration+1	Read
3714. Longest Balanced Substring II	Medium	42.0%	Hash Table Prefix Sum+1	Read
3713. Longest Balanced Substring I	Medium	69.7%	Counting Enumeration+2	Read
3747. Count Distinct Integers After Removing Zeros	Medium	23.1%	Dynamic Programming Math	Read
3692. Majority Frequency Characters	Easy	66.3%	Counting Hash Table+1	Read
3707. Equal Score Substrings	Easy	56.7%	Prefix Sum String	Read
3726. Remove Zeros in Decimal Representation	Easy	75.7%	Math Simulation	Read
3682. Minimum Index Sum of Common Elements	Medium	77.5%	Array Hash Table	Read
3704. Count No-Zero Pairs That Sum to N	Hard	15.6%	Dynamic Programming Math	Read
3733. Minimum Time to Complete All Deliveries	Medium	35.4%	Binary Search Math	Read
3721. Longest Balanced Subarray II	Hard	33.7%	Array Divide and Conquer+3	Read
3719. Longest Balanced Subarray I	Medium	65.6%	Array Divide and Conquer+3	Read
3849. Maximum Bitwise XOR After Rearrangement	Medium	70.4%	Bit Manipulation Greedy+1	Read
3724. Minimum Operations to Transform Array	Medium	39.5%	Array Greedy	Read
3693. Climbing Stairs II	Medium	63.9%	Array Dynamic Programming	Read
3697. Compute Decimal Representation	Easy	64.7%	Array Math	Read
3734. Lexicographically Smallest Palindromic Permutation Greater Than Target	Hard	56.0%	Enumeration String+1	Read
3672. Sum of Weighted Modes in Subarrays	Medium	53.7%	Array Counting+3	Read
3710. Maximum Partition Factor	Hard	31.8%	Array Binary Search+4	Read
3702. Longest Subsequence With Non-Zero Bitwise XOR	Medium	55.1%	Array Bit Manipulation	Read
3825. Longest Strictly Increasing Subsequence With Non-Zero Bitwise AND	Medium	49.5%	Array Binary Search+2	Read
3743. Maximize Cyclic Partition Score	Hard	14.5%	Array Dynamic Programming	Read
3667. Sort Array By Absolute Value	Easy	86.7%	Array Math+2	Read
3686. Number of Stable Subsequences	Hard	60.2%	Array Dynamic Programming	Read
3857. Minimum Cost to Split into Ones	Medium	82.6%	Dynamic Programming Math	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
3694. Distinct Points Reachable After Substring Removal	Medium	53.9%	Hash Table Prefix Sum+2	Read
3720. Lexicographically Smallest Permutation Greater Than Target	Medium	48.2%	Counting Enumeration+3	Read
3703. Remove K-Balanced Substrings	Medium	33.1%	Simulation Stack+1	Read
3776. Minimum Moves to Balance Circular Array	Medium	40.2%	Array Greedy+1	Read

#3752Medium

Lexicographically Smallest Negated Permutation that Sums to Target

ArrayGreedyMath+2

Acceptance: 31.5%

#3739Hard

Count Subarrays With Majority Element II

ArrayDivide and ConquerHash Table+3

Acceptance: 65.2%

#3737Medium

Count Subarrays With Majority Element I

ArrayCountingDivide and Conquer+4

Acceptance: 75.7%

#3722Medium

Lexicographically Smallest String After Reverse

Binary SearchEnumerationTwo Pointers

Acceptance: 53.9%

#3786Hard

Total Sum of Interaction Cost in Tree Groups

ArrayDepth-First SearchTree

Acceptance: 54.3%

#3799Medium

Word Squares II

ArrayBacktrackingEnumeration+2

Acceptance: 53.8%

#3706Medium

Maximum Distance Between Unequal Words in Array II

ArrayString

Acceptance: 71.5%

#3725Hard

Count Ways to Choose Coprime Integers from Rows

ArrayCombinatoricsDynamic Programming+3

Acceptance: 46.8%

#3712Easy

Sum of Elements With Frequency Divisible by K

ArrayCountingHash Table

Acceptance: 77.7%

#3815Medium

Design Auction System

DesignHash TableHeap (Priority Queue)+1

Acceptance: 41.9%

#3696Easy

Maximum Distance Between Unequal Words in Array I

ArrayString

Acceptance: 81.7%

#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%

#3840Medium

House Robber V

ArrayDynamic Programming

Acceptance: 53.3%

#3785Hard

Minimum Swaps to Avoid Forbidden Values

ArrayCountingGreedy+1

Acceptance: 31.0%

#3687Easy

Library Late Fee Calculator

ArraySimulation

Acceptance: 94.4%

#3709Medium

Design Exam Scores Tracker

ArrayBinary SearchDesign+1

Acceptance: 44.0%

#3701Easy

Compute Alternating Sum

ArraySimulation

Acceptance: 89.8%

#3751Medium

Total Waviness of Numbers in Range I

Dynamic ProgrammingEnumerationMath

Acceptance: 86.9%

#3714Medium

Longest Balanced Substring II

Hash TablePrefix SumString

Acceptance: 42.0%

#3713Medium

Longest Balanced Substring I

CountingEnumerationHash Table+1

Acceptance: 69.7%

#3747Medium

Count Distinct Integers After Removing Zeros

Dynamic ProgrammingMath

Acceptance: 23.1%

#3692Easy

Majority Frequency Characters

CountingHash TableString

Acceptance: 66.3%

#3707Easy

Equal Score Substrings

Prefix SumString

Acceptance: 56.7%

#3726Easy

Remove Zeros in Decimal Representation

MathSimulation

Acceptance: 75.7%

#3682Medium

Minimum Index Sum of Common Elements

ArrayHash Table

Acceptance: 77.5%

#3704Hard

Count No-Zero Pairs That Sum to N

Dynamic ProgrammingMath

Acceptance: 15.6%

#3733Medium

Minimum Time to Complete All Deliveries

Binary SearchMath

Acceptance: 35.4%

#3721Hard

Longest Balanced Subarray II

ArrayDivide and ConquerHash Table+2

Acceptance: 33.7%

#3719Medium

Longest Balanced Subarray I

ArrayDivide and ConquerHash Table+2

Acceptance: 65.6%

#3849Medium

Maximum Bitwise XOR After Rearrangement

Bit ManipulationGreedyString

Acceptance: 70.4%

#3724Medium

Minimum Operations to Transform Array

ArrayGreedy

Acceptance: 39.5%

#3693Medium

Climbing Stairs II

ArrayDynamic Programming

Acceptance: 63.9%

#3697Easy

Compute Decimal Representation

ArrayMath

Acceptance: 64.7%

#3734Hard

Lexicographically Smallest Palindromic Permutation Greater Than Target

EnumerationStringTwo Pointers

Acceptance: 56.0%

#3672Medium

Sum of Weighted Modes in Subarrays

ArrayCountingHash Table+2

Acceptance: 53.7%

#3710Hard

Maximum Partition Factor

ArrayBinary SearchBreadth-First Search+3

Acceptance: 31.8%

#3702Medium

Longest Subsequence With Non-Zero Bitwise XOR

ArrayBit Manipulation

Acceptance: 55.1%

#3825Medium

Longest Strictly Increasing Subsequence With Non-Zero Bitwise AND

ArrayBinary SearchBit Manipulation+1

Acceptance: 49.5%

#3743Hard

Maximize Cyclic Partition Score

ArrayDynamic Programming

Acceptance: 14.5%

#3667Easy

Sort Array By Absolute Value

ArrayMathSorting+1

Acceptance: 86.7%

#3686Hard

Number of Stable Subsequences

ArrayDynamic Programming

Acceptance: 60.2%

#3857Medium

Minimum Cost to Split into Ones

Dynamic ProgrammingMath

Acceptance: 82.6%

#3677Hard

Count Binary Palindromic Numbers

Bit ManipulationMath

Acceptance: 33.2%

#3762Hard

Minimum Operations to Equalize Subarrays

ArrayBinary SearchMath+1

Acceptance: 21.3%

#3694Medium

Distinct Points Reachable After Substring Removal

Hash TablePrefix SumSliding Window+1

Acceptance: 53.9%

#3720Medium

Lexicographically Smallest Permutation Greater Than Target

CountingEnumerationGreedy+2

Acceptance: 48.2%

#3703Medium

Remove K-Balanced Substrings

SimulationStackString

Acceptance: 33.1%

#3776Medium

Minimum Moves to Balance Circular Array

ArrayGreedySorting

Acceptance: 40.2%

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