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
3514. Number of Unique XOR Triplets II	Medium	52.9%	Array Bit Manipulation+2	Read
3531. Count Covered Buildings	Medium	58.8%	Array Hash Table+1	Read
3476. Maximize Profit from Task Assignment	Medium	65.9%	Array Greedy+2	Read
3556. Sum of Largest Prime Substrings	Medium	37.9%	Hash Table Math+3	Read
3517. Smallest Palindromic Rearrangement I	Medium	74.5%	Counting Sort Sorting+1	Read
3493. Properties Graph	Medium	48.6%	Array Breadth-First Search+4	Read
3796. Find Maximum Value in a Constrained Sequence	Medium	60.7%	Array Greedy	Read
3466. Maximum Coin Collection	Medium	52.8%	Array Dynamic Programming	Read
3499. Maximize Active Section with Trade I	Medium	60.9%	Enumeration String	Read
3598. Longest Common Prefix Between Adjacent Strings After Removals	Medium	32.4%	Array String	Read
3484. Design Spreadsheet	Medium	73.5%	Array Design+3	Read
3460. Longest Common Prefix After at Most One Removal	Medium	68.3%	String Two Pointers	Read
3489. Zero Array Transformation IV	Medium	31.6%	Array Dynamic Programming	Read
3494. Find the Minimum Amount of Time to Brew Potions	Medium	62.7%	Array Prefix Sum+1	Read
3503. Longest Palindrome After Substring Concatenation I	Medium	43.8%	Dynamic Programming Enumeration+2	Read
3479. Fruits Into Baskets III	Medium	39.2%	Array Binary Search+2	Read
3472. Longest Palindromic Subsequence After at Most K Operations	Medium	38.0%	Dynamic Programming String	Read
3468. Find the Number of Copy Arrays	Medium	46.9%	Array Math	Read
3437. Permutations III	Medium	86.2%	Array Backtracking	Read
3457. Eat Pizzas!	Medium	33.8%	Array Greedy+1	Read
3469. Find Minimum Cost to Remove Array Elements	Medium	22.2%	Array Dynamic Programming	Read
3458. Select K Disjoint Special Substrings	Medium	19.2%	Dynamic Programming Greedy+3	Read
3627. Maximum Median Sum of Subsequences of Size 3	Medium	65.1%	Array Game Theory+3	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
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
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
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
3446. Sort Matrix by Diagonals	Medium	84.7%	Array Matrix+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
3523. Make Array Non-decreasing	Medium	57.5%	Array Greedy+2	Read
3429. Paint House IV	Medium	44.8%	Array Dynamic Programming	Read
3391. Design a 3D Binary Matrix with Efficient Layer Tracking	Medium	66.1%	Array Design+4	Read
3522. Calculate Score After Performing Instructions	Medium	57.0%	Array Hash Table+2	Read
3528. Unit Conversion I	Medium	53.3%	Breadth-First Search Depth-First Search+1	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
3409. Longest Subsequence With Decreasing Adjacent Difference	Medium	16.7%	Array Dynamic Programming	Read
3413. Maximum Coins From K Consecutive Bags	Medium	27.3%	Array Binary Search+4	Read
3428. Maximum and Minimum Sums of at Most Size K Subsequences	Medium	21.7%	Array Combinatorics+3	Read
3424. Minimum Cost to Make Arrays Identical	Medium	38.3%	Array Greedy+1	Read
3527. Find the Most Common Response	Medium	74.0%	Array Counting+2	Read

#3514Medium

Number of Unique XOR Triplets II

ArrayBit ManipulationEnumeration+1

Acceptance: 52.9%

#3531Medium

Count Covered Buildings

ArrayHash TableSorting

Acceptance: 58.8%

#3476Medium

Maximize Profit from Task Assignment

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 65.9%

#3556Medium

Sum of Largest Prime Substrings

Hash TableMathNumber Theory+2

Acceptance: 37.9%

#3517Medium

Smallest Palindromic Rearrangement I

Counting SortSortingString

Acceptance: 74.5%

#3493Medium

Properties Graph

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 48.6%

#3796Medium

Find Maximum Value in a Constrained Sequence

ArrayGreedy

Acceptance: 60.7%

#3466Medium

Maximum Coin Collection

ArrayDynamic Programming

Acceptance: 52.8%

#3499Medium

Maximize Active Section with Trade I

EnumerationString

Acceptance: 60.9%

#3598Medium

Longest Common Prefix Between Adjacent Strings After Removals

ArrayString

Acceptance: 32.4%

#3484Medium

Design Spreadsheet

ArrayDesignHash Table+2

Acceptance: 73.5%

#3460Medium

Longest Common Prefix After at Most One Removal

StringTwo Pointers

Acceptance: 68.3%

#3489Medium

Zero Array Transformation IV

ArrayDynamic Programming

Acceptance: 31.6%

#3494Medium

Find the Minimum Amount of Time to Brew Potions

ArrayPrefix SumSimulation

Acceptance: 62.7%

#3503Medium

Longest Palindrome After Substring Concatenation I

Dynamic ProgrammingEnumerationString+1

Acceptance: 43.8%

#3479Medium

Fruits Into Baskets III

ArrayBinary SearchOrdered Set+1

Acceptance: 39.2%

#3472Medium

Longest Palindromic Subsequence After at Most K Operations

Dynamic ProgrammingString

Acceptance: 38.0%

#3468Medium

Find the Number of Copy Arrays

ArrayMath

Acceptance: 46.9%

#3437Medium

Permutations III

ArrayBacktracking

Acceptance: 86.2%

#3457Medium

Eat Pizzas!

ArrayGreedySorting

Acceptance: 33.8%

#3469Medium

Find Minimum Cost to Remove Array Elements

ArrayDynamic Programming

Acceptance: 22.2%

#3458Medium

Select K Disjoint Special Substrings

Dynamic ProgrammingGreedyHash Table+2

Acceptance: 19.2%

#3627Medium

Maximum Median Sum of Subsequences of Size 3

ArrayGame TheoryGreedy+2

Acceptance: 65.1%

#3462Medium

Maximum Sum With at Most K Elements

ArrayGreedyHeap (Priority Queue)+2

Acceptance: 60.6%

#3453Medium

Separate Squares I

ArrayBinary Search

Acceptance: 58.0%

#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%

#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%

#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%

#3446Medium

Sort Matrix by Diagonals

ArrayMatrixSorting

Acceptance: 84.7%

#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%

#3523Medium

Make Array Non-decreasing

ArrayGreedyMonotonic Stack+1

Acceptance: 57.5%

#3429Medium

Paint House IV

ArrayDynamic Programming

Acceptance: 44.8%

#3391Medium

Design a 3D Binary Matrix with Efficient Layer Tracking

ArrayDesignHash Table+3

Acceptance: 66.1%

#3522Medium

Calculate Score After Performing Instructions

ArrayHash TableSimulation+1

Acceptance: 57.0%

#3528Medium

Unit Conversion I

Breadth-First SearchDepth-First SearchGraph

Acceptance: 53.3%

#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%

#3409Medium

Longest Subsequence With Decreasing Adjacent Difference

ArrayDynamic Programming

Acceptance: 16.7%

#3413Medium

Maximum Coins From K Consecutive Bags

ArrayBinary SearchGreedy+3

Acceptance: 27.3%

#3428Medium

Maximum and Minimum Sums of at Most Size K Subsequences

ArrayCombinatoricsDynamic Programming+2

Acceptance: 21.7%

#3424Medium

Minimum Cost to Make Arrays Identical

ArrayGreedySorting

Acceptance: 38.3%

#3527Medium

Find the Most Common Response

ArrayCountingHash Table+1

Acceptance: 74.0%

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