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
3467. Transform Array by Parity	Easy	89.7%	Array Counting+1	Read
3509. Maximum Product of Subsequences With an Alternating Sum Equal to K	Hard	13.7%	Array Dynamic Programming+1	Read
3469. Find Minimum Cost to Remove Array Elements	Medium	22.2%	Array Dynamic Programming	Read
3454. Separate Squares II	Hard	59.2%	Array Binary Search+2	Read
3463. Check If Digits Are Equal in String After Operations II	Hard	14.3%	Combinatorics Math+2	Read
3507. Minimum Pair Removal to Sort Array I	Easy	65.3%	Array Doubly-Linked List+5	Read
3510. Minimum Pair Removal to Sort Array II	Hard	39.1%	Array Doubly-Linked List+5	Read
3458. Select K Disjoint Special Substrings	Medium	19.2%	Dynamic Programming Greedy+3	Read
3474. Lexicographically Smallest Generated String	Hard	53.3%	Greedy String+1	Read
3461. Check If Digits Are Equal in String After Operations I	Easy	82.5%	Combinatorics Math+3	Read
3627. Maximum Median Sum of Subsequences of Size 3	Medium	65.1%	Array Game Theory+3	Read
3500. Minimum Cost to Divide Array Into Subarrays	Hard	27.6%	Array Dynamic Programming+1	Read
3462. Maximum Sum With at Most K Elements	Medium	60.6%	Array Greedy+3	Read
3453. Separate Squares I	Medium	58.0%	Array Binary Search	Read
3449. Maximize the Minimum Game Score	Hard	26.2%	Array Binary Search+1	Read
3445. Maximum Difference Between Even and Odd Frequency II	Hard	48.7%	Enumeration Prefix Sum+2	Read
3447. Assign Elements to Groups with Constraints	Medium	26.8%	Array Hash Table	Read
3478. Choose K Elements With Maximum Sum	Medium	34.0%	Array Heap (Priority Queue)+1	Read
3431. Minimum Unlocked Indices to Sort Nums	Medium	57.6%	Array Hash Table	Read
3416. Subsequences with a Unique Middle Mode II	Hard	16.3%	Array Combinatorics+2	Read
3584. Maximum Product of First and Last Elements of a Subsequence	Medium	31.9%	Array Two Pointers	Read
3443. Maximum Manhattan Distance After K Changes	Medium	54.2%	Counting Hash Table+2	Read
3442. Maximum Difference Between Even and Odd Frequency I	Easy	60.7%	Counting Hash Table+1	Read
3535. Unit Conversion II	Medium	65.3%	Array Breadth-First Search+3	Read
3434. Maximum Frequency After Subarray Operation	Medium	31.6%	Array Dynamic Programming+4	Read
3488. Closest Equal Element Queries	Medium	51.4%	Array Binary Search+1	Read
3406. Find the Lexicographically Largest String From the Box II	Hard	48.9%	String Two Pointers	Read
3446. Sort Matrix by Diagonals	Medium	84.7%	Array Matrix+1	Read
3423. Maximum Difference Between Adjacent Elements in a Circular Array	Easy	75.7%	Array	Read
3495. Minimum Operations to Make Array Elements Zero	Hard	60.4%	Array Bit Manipulation+1	Read
3439. Reschedule Meetings for Maximum Free Time I	Medium	53.9%	Array Greedy+1	Read
3440. Reschedule Meetings for Maximum Free Time II	Medium	60.4%	Array Enumeration+1	Read
3400. Maximum Number of Matching Indices After Right Shifts	Medium	84.7%	Array Simulation+1	Read
3426. Manhattan Distances of All Arrangements of Pieces	Hard	33.5%	Combinatorics Math	Read
3523. Make Array Non-decreasing	Medium	57.5%	Array Greedy+2	Read
3429. Paint House IV	Medium	44.8%	Array Dynamic Programming	Read
3438. Find Valid Pair of Adjacent Digits in String	Easy	60.7%	Counting Hash Table+1	Read
3391. Design a 3D Binary Matrix with Efficient Layer Tracking	Medium	66.1%	Array Design+4	Read
3459. Length of Longest V-Shaped Diagonal Segment	Hard	56.3%	Array Dynamic Programming+2	Read
3522. Calculate Score After Performing Instructions	Medium	57.0%	Array Hash Table+2	Read
3427. Sum of Variable Length Subarrays	Easy	85.6%	Array Prefix Sum	Read
3528. Unit Conversion I	Medium	53.3%	Breadth-First Search Depth-First Search+1	Read
3430. Maximum and Minimum Sums of at Most Size K Subarrays	Hard	25.9%	Array Math+2	Read
3452. Sum of Good Numbers	Easy	69.6%	Array	Read
3473. Sum of K Subarrays With Length at Least M	Medium	26.0%	Array Dynamic Programming+1	Read
3433. Count Mentions Per User	Medium	50.8%	Array Math+2	Read
3419. Minimize the Maximum Edge Weight of Graph	Medium	45.2%	Binary Search Breadth-First Search+3	Read
3383. Minimum Runes to Add to Cast Spell	Hard	45.2%	Array Breadth-First Search+4	Read
3505. Minimum Operations to Make Elements Within K Subarrays Equal	Hard	27.8%	Array Dynamic Programming+4	Read
3409. Longest Subsequence With Decreasing Adjacent Difference	Medium	16.7%	Array Dynamic Programming	Read

#3467Easy

Transform Array by Parity

ArrayCountingSorting

Acceptance: 89.7%

#3509Hard

Maximum Product of Subsequences With an Alternating Sum Equal to K

ArrayDynamic ProgrammingHash Table

Acceptance: 13.7%

#3469Medium

Find Minimum Cost to Remove Array Elements

ArrayDynamic Programming

Acceptance: 22.2%

#3454Hard

Separate Squares II

ArrayBinary SearchLine Sweep+1

Acceptance: 59.2%

#3463Hard

Check If Digits Are Equal in String After Operations II

CombinatoricsMathNumber Theory+1

Acceptance: 14.3%

#3507Easy

Minimum Pair Removal to Sort Array I

ArrayDoubly-Linked ListHash Table+4

Acceptance: 65.3%

#3510Hard

Minimum Pair Removal to Sort Array II

ArrayDoubly-Linked ListHash Table+4

Acceptance: 39.1%

#3458Medium

Select K Disjoint Special Substrings

Dynamic ProgrammingGreedyHash Table+2

Acceptance: 19.2%

#3474Hard

Lexicographically Smallest Generated String

GreedyStringString Matching

Acceptance: 53.3%

#3461Easy

Check If Digits Are Equal in String After Operations I

CombinatoricsMathNumber Theory+2

Acceptance: 82.5%

#3627Medium

Maximum Median Sum of Subsequences of Size 3

ArrayGame TheoryGreedy+2

Acceptance: 65.1%

#3500Hard

Minimum Cost to Divide Array Into Subarrays

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 27.6%

#3462Medium

Maximum Sum With at Most K Elements

ArrayGreedyHeap (Priority Queue)+2

Acceptance: 60.6%

#3453Medium

Separate Squares I

ArrayBinary Search

Acceptance: 58.0%

#3449Hard

Maximize the Minimum Game Score

ArrayBinary SearchGreedy

Acceptance: 26.2%

#3445Hard

Maximum Difference Between Even and Odd Frequency II

EnumerationPrefix SumSliding Window+1

Acceptance: 48.7%

#3447Medium

Assign Elements to Groups with Constraints

ArrayHash Table

Acceptance: 26.8%

#3478Medium

Choose K Elements With Maximum Sum

ArrayHeap (Priority Queue)Sorting

Acceptance: 34.0%

#3431Medium

Minimum Unlocked Indices to Sort Nums

ArrayHash Table

Acceptance: 57.6%

#3416Hard

Subsequences with a Unique Middle Mode II

ArrayCombinatoricsHash Table+1

Acceptance: 16.3%

#3584Medium

Maximum Product of First and Last Elements of a Subsequence

ArrayTwo Pointers

Acceptance: 31.9%

#3443Medium

Maximum Manhattan Distance After K Changes

CountingHash TableMath+1

Acceptance: 54.2%

#3442Easy

Maximum Difference Between Even and Odd Frequency I

CountingHash TableString

Acceptance: 60.7%

#3535Medium

Unit Conversion II

ArrayBreadth-First SearchDepth-First Search+2

Acceptance: 65.3%

#3434Medium

Maximum Frequency After Subarray Operation

ArrayDynamic ProgrammingEnumeration+3

Acceptance: 31.6%

#3488Medium

Closest Equal Element Queries

ArrayBinary SearchHash Table

Acceptance: 51.4%

#3406Hard

Find the Lexicographically Largest String From the Box II

StringTwo Pointers

Acceptance: 48.9%

#3446Medium

Sort Matrix by Diagonals

ArrayMatrixSorting

Acceptance: 84.7%

#3423Easy

Maximum Difference Between Adjacent Elements in a Circular Array

Array

Acceptance: 75.7%

#3495Hard

Minimum Operations to Make Array Elements Zero

ArrayBit ManipulationMath

Acceptance: 60.4%

#3439Medium

Reschedule Meetings for Maximum Free Time I

ArrayGreedySliding Window

Acceptance: 53.9%

#3440Medium

Reschedule Meetings for Maximum Free Time II

ArrayEnumerationGreedy

Acceptance: 60.4%

#3400Medium

Maximum Number of Matching Indices After Right Shifts

ArraySimulationTwo Pointers

Acceptance: 84.7%

#3426Hard

Manhattan Distances of All Arrangements of Pieces

CombinatoricsMath

Acceptance: 33.5%

#3523Medium

Make Array Non-decreasing

ArrayGreedyMonotonic Stack+1

Acceptance: 57.5%

#3429Medium

Paint House IV

ArrayDynamic Programming

Acceptance: 44.8%

#3438Easy

Find Valid Pair of Adjacent Digits in String

CountingHash TableString

Acceptance: 60.7%

#3391Medium

Design a 3D Binary Matrix with Efficient Layer Tracking

ArrayDesignHash Table+3

Acceptance: 66.1%

#3459Hard

Length of Longest V-Shaped Diagonal Segment

ArrayDynamic ProgrammingMatrix+1

Acceptance: 56.3%

#3522Medium

Calculate Score After Performing Instructions

ArrayHash TableSimulation+1

Acceptance: 57.0%

#3427Easy

Sum of Variable Length Subarrays

ArrayPrefix Sum

Acceptance: 85.6%

#3528Medium

Unit Conversion I

Breadth-First SearchDepth-First SearchGraph

Acceptance: 53.3%

#3430Hard

Maximum and Minimum Sums of at Most Size K Subarrays

ArrayMathMonotonic Stack+1

Acceptance: 25.9%

#3452Easy

Sum of Good Numbers

Array

Acceptance: 69.6%

#3473Medium

Sum of K Subarrays With Length at Least M

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 26.0%

#3433Medium

Count Mentions Per User

ArrayMathSimulation+1

Acceptance: 50.8%

#3419Medium

Minimize the Maximum Edge Weight of Graph

Binary SearchBreadth-First SearchDepth-First Search+2

Acceptance: 45.2%

#3383Hard

Minimum Runes to Add to Cast Spell

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 45.2%

#3505Hard

Minimum Operations to Make Elements Within K Subarrays Equal

ArrayDynamic ProgrammingHash Table+3

Acceptance: 27.8%

#3409Medium

Longest Subsequence With Decreasing Adjacent Difference

ArrayDynamic Programming

Acceptance: 16.7%

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