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
3542. Minimum Operations to Convert All Elements to Zero	Medium	53.0%	Array Greedy+3	Read
3538. Merge Operations for Minimum Travel Time	Hard	30.5%	Array Dynamic Programming+1	Read
3502. Minimum Cost to Reach Every Position	Easy	82.6%	Array	Read
3524. Find X Value of Array I	Medium	66.5%	Array Dynamic Programming+1	Read
3516. Find Closest Person	Easy	88.9%	Math	Read
3515. Shortest Path in a Weighted Tree	Hard	41.5%	Array Binary Indexed Tree+3	Read
3508. Implement Router	Medium	39.1%	Array Binary Search+4	Read
3530. Maximum Profit from Valid Topological Order in DAG	Hard	29.7%	Array Bit Manipulation+4	Read
3481. Apply Substitutions	Medium	78.0%	Array Breadth-First Search+5	Read
3513. Number of Unique XOR Triplets I	Medium	57.2%	Array Bit Manipulation+1	Read
3619. Count Islands With Total Value Divisible by K	Medium	55.5%	Array Breadth-First Search+3	Read
3537. Fill a Special Grid	Medium	70.8%	Array Divide and Conquer+1	Read
3529. Count Cells in Overlapping Horizontal and Vertical Substrings	Medium	27.7%	Array Hash Function+4	Read
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
3492. Maximum Containers on a Ship	Easy	75.2%	Math	Read
3556. Sum of Largest Prime Substrings	Medium	37.9%	Hash Table Math+3	Read
3506. Find Time Required to Eliminate Bacterial Strains	Hard	63.2%	Array Greedy+2	Read
3518. Smallest Palindromic Rearrangement II	Hard	44.3%	Combinatorics Counting+3	Read
3517. Smallest Palindromic Rearrangement I	Medium	74.5%	Counting Sort Sorting+1	Read
3498. Reverse Degree of a String	Easy	91.9%	Simulation String	Read
3519. Count Numbers with Non-Decreasing Digits	Hard	37.3%	Dynamic Programming Math+1	Read
3493. Properties Graph	Medium	48.6%	Array Breadth-First Search+4	Read
3504. Longest Palindrome After Substring Concatenation II	Hard	18.4%	Dynamic Programming String+1	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
3501. Maximize Active Section with Trade II	Hard	64.7%	Array Binary Search+2	Read
3490. Count Beautiful Numbers	Hard	24.5%	Dynamic Programming	Read
3598. Longest Common Prefix Between Adjacent Strings After Removals	Medium	32.4%	Array String	Read
3483. Unique 3-Digit Even Numbers	Easy	79.8%	Array Enumeration+2	Read
3486. Longest Special Path II	Hard	19.8%	Array Depth-First Search+3	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
3477. Fruits Into Baskets II	Easy	70.2%	Array Binary Search+3	Read
3480. Maximize Subarrays After Removing One Conflicting Pair	Hard	64.6%	Array Enumeration+2	Read
3487. Maximum Unique Subarray Sum After Deletion	Easy	40.5%	Array Greedy+1	Read
3450. Maximum Students on a Single Bench	Easy	87.8%	Array Hash Table	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
3485. Longest Common Prefix of K Strings After Removal	Hard	24.3%	Array String+1	Read
3470. Permutations IV	Hard	32.8%	Array Combinatorics+2	Read
3464. Maximize the Distance Between Points on a Square	Hard	51.3%	Array Binary Search+3	Read
3437. Permutations III	Medium	86.2%	Array Backtracking	Read
3457. Eat Pizzas!	Medium	33.8%	Array Greedy+1	Read

#3542Medium

Minimum Operations to Convert All Elements to Zero

ArrayGreedyHash Table+2

Acceptance: 53.0%

#3538Hard

Merge Operations for Minimum Travel Time

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 30.5%

#3502Easy

Minimum Cost to Reach Every Position

Array

Acceptance: 82.6%

#3524Medium

Find X Value of Array I

ArrayDynamic ProgrammingMath

Acceptance: 66.5%

#3516Easy

Find Closest Person

Math

Acceptance: 88.9%

#3515Hard

Shortest Path in a Weighted Tree

ArrayBinary Indexed TreeDepth-First Search+2

Acceptance: 41.5%

#3508Medium

Implement Router

ArrayBinary SearchDesign+3

Acceptance: 39.1%

#3530Hard

Maximum Profit from Valid Topological Order in DAG

ArrayBit ManipulationBitmask+3

Acceptance: 29.7%

#3481Medium

Apply Substitutions

ArrayBreadth-First SearchDepth-First Search+4

Acceptance: 78.0%

#3513Medium

Number of Unique XOR Triplets I

ArrayBit ManipulationMath

Acceptance: 57.2%

#3619Medium

Count Islands With Total Value Divisible by K

ArrayBreadth-First SearchDepth-First Search+2

Acceptance: 55.5%

#3537Medium

Fill a Special Grid

ArrayDivide and ConquerMatrix

Acceptance: 70.8%

#3529Medium

Count Cells in Overlapping Horizontal and Vertical Substrings

ArrayHash FunctionMatrix+3

Acceptance: 27.7%

#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%

#3492Easy

Maximum Containers on a Ship

Math

Acceptance: 75.2%

#3556Medium

Sum of Largest Prime Substrings

Hash TableMathNumber Theory+2

Acceptance: 37.9%

#3506Hard

Find Time Required to Eliminate Bacterial Strains

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 63.2%

#3518Hard

Smallest Palindromic Rearrangement II

CombinatoricsCountingHash Table+2

Acceptance: 44.3%

#3517Medium

Smallest Palindromic Rearrangement I

Counting SortSortingString

Acceptance: 74.5%

#3498Easy

Reverse Degree of a String

SimulationString

Acceptance: 91.9%

#3519Hard

Count Numbers with Non-Decreasing Digits

Dynamic ProgrammingMathString

Acceptance: 37.3%

#3493Medium

Properties Graph

ArrayBreadth-First SearchDepth-First Search+3

Acceptance: 48.6%

#3504Hard

Longest Palindrome After Substring Concatenation II

Dynamic ProgrammingStringTwo Pointers

Acceptance: 18.4%

#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%

#3501Hard

Maximize Active Section with Trade II

ArrayBinary SearchSegment Tree+1

Acceptance: 64.7%

#3490Hard

Count Beautiful Numbers

Dynamic Programming

Acceptance: 24.5%

#3598Medium

Longest Common Prefix Between Adjacent Strings After Removals

ArrayString

Acceptance: 32.4%

#3483Easy

Unique 3-Digit Even Numbers

ArrayEnumerationHash Table+1

Acceptance: 79.8%

#3486Hard

Longest Special Path II

ArrayDepth-First SearchHash Table+2

Acceptance: 19.8%

#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%

#3477Easy

Fruits Into Baskets II

ArrayBinary SearchOrdered Set+2

Acceptance: 70.2%

#3480Hard

Maximize Subarrays After Removing One Conflicting Pair

ArrayEnumerationPrefix Sum+1

Acceptance: 64.6%

#3487Easy

Maximum Unique Subarray Sum After Deletion

ArrayGreedyHash Table

Acceptance: 40.5%

#3450Easy

Maximum Students on a Single Bench

ArrayHash Table

Acceptance: 87.8%

#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%

#3485Hard

Longest Common Prefix of K Strings After Removal

ArrayStringTrie

Acceptance: 24.3%

#3470Hard

Permutations IV

ArrayCombinatoricsEnumeration+1

Acceptance: 32.8%

#3464Hard

Maximize the Distance Between Points on a Square

ArrayBinary SearchGeometry+2

Acceptance: 51.3%

#3437Medium

Permutations III

ArrayBacktracking

Acceptance: 86.2%

#3457Medium

Eat Pizzas!

ArrayGreedySorting

Acceptance: 33.8%

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Master DSA with Step-by-Step Solutions

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