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
3562. Maximum Profit from Trading Stocks with Discounts	Hard	56.1%	Array Depth-First Search+2	Read
3553. Minimum Weighted Subgraph With the Required Paths II	Hard	47.6%	Array Bit Manipulation+3	Read
3534. Path Existence Queries in a Graph II	Hard	64.2%	Array Binary Search+6	Read
3539. Find Sum of Array Product of Magical Sequences	Hard	61.9%	Array Bit Manipulation+4	Read
3548. Equal Sum Grid Partition II	Hard	39.5%	Array Enumeration+3	Read
3547. Maximum Sum of Edge Values in a Graph	Hard	37.6%	Graph Greedy+1	Read
3559. Number of Ways to Assign Edge Weights II	Hard	71.8%	Array Bit Manipulation+4	Read
3533. Concatenated Divisibility	Hard	30.6%	Array Bit Manipulation+2	Read
3525. Find X Value of Array II	Hard	45.5%	Array Math+1	Read
3538. Merge Operations for Minimum Travel Time	Hard	30.5%	Array Dynamic Programming+1	Read
3515. Shortest Path in a Weighted Tree	Hard	41.5%	Array Binary Indexed Tree+3	Read
3530. Maximum Profit from Valid Topological Order in DAG	Hard	29.7%	Array Bit Manipulation+4	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
3519. Count Numbers with Non-Decreasing Digits	Hard	37.3%	Dynamic Programming Math+1	Read
3504. Longest Palindrome After Substring Concatenation II	Hard	18.4%	Dynamic Programming String+1	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
3486. Longest Special Path II	Hard	19.8%	Array Depth-First Search+3	Read
3480. Maximize Subarrays After Removing One Conflicting Pair	Hard	64.6%	Array Enumeration+2	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
3509. Maximum Product of Subsequences With an Alternating Sum Equal to K	Hard	13.7%	Array Dynamic Programming+1	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
3510. Minimum Pair Removal to Sort Array II	Hard	39.1%	Array Doubly-Linked List+5	Read
3474. Lexicographically Smallest Generated String	Hard	53.3%	Greedy String+1	Read
3500. Minimum Cost to Divide Array Into Subarrays	Hard	27.6%	Array Dynamic Programming+1	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
3416. Subsequences with a Unique Middle Mode II	Hard	16.3%	Array Combinatorics+2	Read
3406. Find the Lexicographically Largest String From the Box II	Hard	48.9%	String Two Pointers	Read
3495. Minimum Operations to Make Array Elements Zero	Hard	60.4%	Array Bit Manipulation+1	Read
3426. Manhattan Distances of All Arrangements of Pieces	Hard	33.5%	Combinatorics Math	Read
3459. Length of Longest V-Shaped Diagonal Segment	Hard	56.3%	Array Dynamic Programming+2	Read
3430. Maximum and Minimum Sums of at Most Size K Subarrays	Hard	25.9%	Array Math+2	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
3435. Frequencies of Shortest Supersequences	Hard	22.2%	Array Bit Manipulation+4	Read
3399. Smallest Substring With Identical Characters II	Hard	39.0%	Binary Search String	Read
3441. Minimum Cost Good Caption	Hard	20.5%	Dynamic Programming String	Read
3395. Subsequences with a Unique Middle Mode I	Hard	20.7%	Array Combinatorics+2	Read
3444. Minimum Increments for Target Multiples in an Array	Hard	27.5%	Array Bit Manipulation+4	Read
3448. Count Substrings Divisible By Last Digit	Hard	23.7%	Dynamic Programming String	Read
3385. Minimum Time to Break Locks II	Hard	45.7%	Array Depth-First Search+1	Read
3455. Shortest Matching Substring	Hard	24.5%	Binary Search String+2	Read
3398. Smallest Substring With Identical Characters I	Hard	21.0%	Array Binary Search+1	Read
3382. Maximum Area Rectangle With Point Constraints II	Hard	24.0%	Array Binary Indexed Tree+4	Read
3410. Maximize Subarray Sum After Removing All Occurrences of One Element	Hard	23.0%	Array Dynamic Programming+1	Read

#3562Hard

Maximum Profit from Trading Stocks with Discounts

ArrayDepth-First SearchDynamic Programming+1

Acceptance: 56.1%

#3553Hard

Minimum Weighted Subgraph With the Required Paths II

ArrayBit ManipulationDepth-First Search+2

Acceptance: 47.6%

#3534Hard

Path Existence Queries in a Graph II

ArrayBinary SearchBit Manipulation+5

Acceptance: 64.2%

#3539Hard

Find Sum of Array Product of Magical Sequences

ArrayBit ManipulationBitmask+3

Acceptance: 61.9%

#3548Hard

Equal Sum Grid Partition II

ArrayEnumerationHash Table+2

Acceptance: 39.5%

#3547Hard

Maximum Sum of Edge Values in a Graph

GraphGreedyMath

Acceptance: 37.6%

#3559Hard

Number of Ways to Assign Edge Weights II

ArrayBit ManipulationDepth-First Search+3

Acceptance: 71.8%

#3533Hard

Concatenated Divisibility

ArrayBit ManipulationBitmask+1

Acceptance: 30.6%

#3525Hard

Find X Value of Array II

ArrayMathSegment Tree

Acceptance: 45.5%

#3538Hard

Merge Operations for Minimum Travel Time

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 30.5%

#3515Hard

Shortest Path in a Weighted Tree

ArrayBinary Indexed TreeDepth-First Search+2

Acceptance: 41.5%

#3530Hard

Maximum Profit from Valid Topological Order in DAG

ArrayBit ManipulationBitmask+3

Acceptance: 29.7%

#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%

#3519Hard

Count Numbers with Non-Decreasing Digits

Dynamic ProgrammingMathString

Acceptance: 37.3%

#3504Hard

Longest Palindrome After Substring Concatenation II

Dynamic ProgrammingStringTwo Pointers

Acceptance: 18.4%

#3501Hard

Maximize Active Section with Trade II

ArrayBinary SearchSegment Tree+1

Acceptance: 64.7%

#3490Hard

Count Beautiful Numbers

Dynamic Programming

Acceptance: 24.5%

#3486Hard

Longest Special Path II

ArrayDepth-First SearchHash Table+2

Acceptance: 19.8%

#3480Hard

Maximize Subarrays After Removing One Conflicting Pair

ArrayEnumerationPrefix Sum+1

Acceptance: 64.6%

#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%

#3509Hard

Maximum Product of Subsequences With an Alternating Sum Equal to K

ArrayDynamic ProgrammingHash Table

Acceptance: 13.7%

#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%

#3510Hard

Minimum Pair Removal to Sort Array II

ArrayDoubly-Linked ListHash Table+4

Acceptance: 39.1%

#3474Hard

Lexicographically Smallest Generated String

GreedyStringString Matching

Acceptance: 53.3%

#3500Hard

Minimum Cost to Divide Array Into Subarrays

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 27.6%

#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%

#3416Hard

Subsequences with a Unique Middle Mode II

ArrayCombinatoricsHash Table+1

Acceptance: 16.3%

#3406Hard

Find the Lexicographically Largest String From the Box II

StringTwo Pointers

Acceptance: 48.9%

#3495Hard

Minimum Operations to Make Array Elements Zero

ArrayBit ManipulationMath

Acceptance: 60.4%

#3426Hard

Manhattan Distances of All Arrangements of Pieces

CombinatoricsMath

Acceptance: 33.5%

#3459Hard

Length of Longest V-Shaped Diagonal Segment

ArrayDynamic ProgrammingMatrix+1

Acceptance: 56.3%

#3430Hard

Maximum and Minimum Sums of at Most Size K Subarrays

ArrayMathMonotonic Stack+1

Acceptance: 25.9%

#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%

#3435Hard

Frequencies of Shortest Supersequences

ArrayBit ManipulationEnumeration+3

Acceptance: 22.2%

#3399Hard

Smallest Substring With Identical Characters II

Binary SearchString

Acceptance: 39.0%

#3441Hard

Minimum Cost Good Caption

Dynamic ProgrammingString

Acceptance: 20.5%

#3395Hard

Subsequences with a Unique Middle Mode I

ArrayCombinatoricsHash Table+1

Acceptance: 20.7%

#3444Hard

Minimum Increments for Target Multiples in an Array

ArrayBit ManipulationBitmask+3

Acceptance: 27.5%

#3448Hard

Count Substrings Divisible By Last Digit

Dynamic ProgrammingString

Acceptance: 23.7%

#3385Hard

Minimum Time to Break Locks II

ArrayDepth-First SearchGraph

Acceptance: 45.7%

#3455Hard

Shortest Matching Substring

Binary SearchStringString Matching+1

Acceptance: 24.5%

#3398Hard

Smallest Substring With Identical Characters I

ArrayBinary SearchEnumeration

Acceptance: 21.0%

#3382Hard

Maximum Area Rectangle With Point Constraints II

ArrayBinary Indexed TreeGeometry+3

Acceptance: 24.0%

#3410Hard

Maximize Subarray Sum After Removing All Occurrences of One Element

ArrayDynamic ProgrammingSegment Tree

Acceptance: 23.0%

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