Solutions & Explanations

Browse 4,030+ detailed solutions with multiple approaches, code in Python, Java, C++ and more.

4,030 Solutions961 Easy2102 Medium967 Hard

Title	Difficulty	Acceptance	Topics	Solution
1001. Grid Illumination	Hard	39.7%	Array Hash Table	Read
1002. Find Common Characters	Easy	74.6%	Array Hash Table+1	Read
1003. Check If Word Is Valid After Substitutions	Medium	61.1%	Stack String	Read
1004. Max Consecutive Ones III	Medium	68.0%	Array Binary Search+2	Read
1005. Maximize Sum Of Array After K Negations	Easy	54.3%	Array Greedy+1	Read
1006. Clumsy Factorial	Medium	61.8%	Math Simulation+1	Read
1007. Minimum Domino Rotations For Equal Row	Medium	56.5%	Array Greedy	Read
1008. Construct Binary Search Tree from Preorder Traversal	Medium	84.1%	Array Binary Search Tree+4	Read
1009. Complement of Base 10 Integer	Easy	63.3%	Bit Manipulation	Read
1010. Pairs of Songs With Total Durations Divisible by 60	Medium	53.1%	Array Counting+1	Read
1011. Capacity To Ship Packages Within D Days	Medium	74.2%	Array Binary Search	Read
1012. Numbers With Repeated Digits	Hard	48.3%	Dynamic Programming Math	Read
1013. Partition Array Into Three Parts With Equal Sum	Easy	42.6%	Array Greedy	Read
1014. Best Sightseeing Pair	Medium	62.7%	Array Dynamic Programming	Read
1015. Smallest Integer Divisible by K	Medium	54.4%	Hash Table Math	Read
1016. Binary String With Substrings Representing 1 To N	Medium	58.5%	String	Read
1017. Convert to Base -2	Medium	63.0%	Math	Read
1018. Binary Prefix Divisible By 5	Easy	53.5%	Array Bit Manipulation	Read
1019. Next Greater Node In Linked List	Medium	64.6%	Array Linked List+2	Read
1020. Number of Enclaves	Medium	72.2%	Array Breadth-First Search+3	Read
1021. Remove Outermost Parentheses	Easy	87.5%	Stack String	Read
1022. Sum of Root To Leaf Binary Numbers	Easy	76.6%	Binary Tree Depth-First Search+1	Read
1023. Camelcase Matching	Medium	65.8%	Array String+3	Read
1024. Video Stitching	Medium	52.6%	Array Dynamic Programming+1	Read
1025. Divisor Game	Easy	72.3%	Brainteaser Dynamic Programming+2	Read
1026. Maximum Difference Between Node and Ancestor	Medium	78.1%	Binary Tree Depth-First Search+1	Read
1027. Longest Arithmetic Subsequence	Medium	49.9%	Array Binary Search+2	Read
1028. Recover a Tree From Preorder Traversal	Hard	83.2%	Binary Tree Depth-First Search+2	Read
1029. Two City Scheduling	Medium	69.0%	Array Greedy+1	Read
1030. Matrix Cells in Distance Order	Easy	74.6%	Array Geometry+3	Read
1031. Maximum Sum of Two Non-Overlapping Subarrays	Medium	61.4%	Array Dynamic Programming+1	Read
1032. Stream of Characters	Hard	52.8%	Array Data Stream+3	Read
1033. Moving Stones Until Consecutive	Medium	52.2%	Brainteaser Math	Read
1034. Coloring A Border	Medium	51.2%	Array Breadth-First Search+2	Read
1035. Uncrossed Lines	Medium	65.1%	Array Dynamic Programming	Read
1036. Escape a Large Maze	Hard	37.0%	Array Breadth-First Search+2	Read
1037. Valid Boomerang	Easy	39.9%	Array Geometry+1	Read
1038. Binary Search Tree to Greater Sum Tree	Medium	88.3%	Binary Search Tree Binary Tree+2	Read
1039. Minimum Score Triangulation of Polygon	Medium	67.4%	Array Dynamic Programming	Read
1040. Moving Stones Until Consecutive II	Medium	59.4%	Array Math+2	Read
1041. Robot Bounded In Circle	Medium	56.6%	Math Simulation+1	Read
1042. Flower Planting With No Adjacent	Medium	54.1%	Breadth-First Search Depth-First Search+1	Read
1043. Partition Array for Maximum Sum	Medium	77.4%	Array Dynamic Programming	Read
1044. Longest Duplicate Substring	Hard	31.1%	Binary Search Hash Function+4	Read
1045. Customers Who Bought All Products	Medium	62.6%	Database	Read
1046. Last Stone Weight	Easy	66.4%	Array Heap (Priority Queue)	Read
1047. Remove All Adjacent Duplicates In String	Easy	73.6%	Stack String	Read
1048. Longest String Chain	Medium	63.5%	Array Dynamic Programming+4	Read
1049. Last Stone Weight II	Medium	60.6%	Array Dynamic Programming	Read
1050. Actors and Directors Who Cooperated At Least Three Times	Easy	70.3%	Database	Read

#1001Hard

Grid Illumination

ArrayHash Table

Acceptance: 39.7%

#1002Easy

Find Common Characters

ArrayHash TableString

Acceptance: 74.6%

#1003Medium

Check If Word Is Valid After Substitutions

StackString

Acceptance: 61.1%

#1004Medium

Max Consecutive Ones III

ArrayBinary SearchPrefix Sum+1

Acceptance: 68.0%

#1005Easy

Maximize Sum Of Array After K Negations

ArrayGreedySorting

Acceptance: 54.3%

#1006Medium

Clumsy Factorial

MathSimulationStack

Acceptance: 61.8%

#1007Medium

Minimum Domino Rotations For Equal Row

ArrayGreedy

Acceptance: 56.5%

#1008Medium

Construct Binary Search Tree from Preorder Traversal

ArrayBinary Search TreeBinary Tree+3

Acceptance: 84.1%

#1009Easy

Complement of Base 10 Integer

Bit Manipulation

Acceptance: 63.3%

#1010Medium

Pairs of Songs With Total Durations Divisible by 60

ArrayCountingHash Table

Acceptance: 53.1%

#1011Medium

Capacity To Ship Packages Within D Days

ArrayBinary Search

Acceptance: 74.2%

#1012Hard

Numbers With Repeated Digits

Dynamic ProgrammingMath

Acceptance: 48.3%

#1013Easy

Partition Array Into Three Parts With Equal Sum

ArrayGreedy

Acceptance: 42.6%

#1014Medium

Best Sightseeing Pair

ArrayDynamic Programming

Acceptance: 62.7%

#1015Medium

Smallest Integer Divisible by K

Hash TableMath

Acceptance: 54.4%

#1016Medium

Binary String With Substrings Representing 1 To N

String

Acceptance: 58.5%

#1017Medium

Convert to Base -2

Math

Acceptance: 63.0%

#1018Easy

Binary Prefix Divisible By 5

ArrayBit Manipulation

Acceptance: 53.5%

#1019Medium

Next Greater Node In Linked List

ArrayLinked ListMonotonic Stack+1

Acceptance: 64.6%

#1020Medium

Number of Enclaves

ArrayBreadth-First SearchDepth-First Search+2

Acceptance: 72.2%

#1021Easy

Remove Outermost Parentheses

StackString

Acceptance: 87.5%

#1022Easy

Sum of Root To Leaf Binary Numbers

Binary TreeDepth-First SearchTree

Acceptance: 76.6%

#1023Medium

Camelcase Matching

ArrayStringString Matching+2

Acceptance: 65.8%

#1024Medium

Video Stitching

ArrayDynamic ProgrammingGreedy

Acceptance: 52.6%

#1025Easy

Divisor Game

BrainteaserDynamic ProgrammingGame Theory+1

Acceptance: 72.3%

#1026Medium

Maximum Difference Between Node and Ancestor

Binary TreeDepth-First SearchTree

Acceptance: 78.1%

#1027Medium

Longest Arithmetic Subsequence

ArrayBinary SearchDynamic Programming+1

Acceptance: 49.9%

#1028Hard

Recover a Tree From Preorder Traversal

Binary TreeDepth-First SearchString+1

Acceptance: 83.2%

#1029Medium

Two City Scheduling

ArrayGreedySorting

Acceptance: 69.0%

#1030Easy

Matrix Cells in Distance Order

ArrayGeometryMath+2

Acceptance: 74.6%

#1031Medium

Maximum Sum of Two Non-Overlapping Subarrays

ArrayDynamic ProgrammingSliding Window

Acceptance: 61.4%

#1032Hard

Stream of Characters

ArrayData StreamDesign+2

Acceptance: 52.8%

#1033Medium

Moving Stones Until Consecutive

BrainteaserMath

Acceptance: 52.2%

#1034Medium

Coloring A Border

ArrayBreadth-First SearchDepth-First Search+1

Acceptance: 51.2%

#1035Medium

Uncrossed Lines

ArrayDynamic Programming

Acceptance: 65.1%

#1036Hard

Escape a Large Maze

ArrayBreadth-First SearchDepth-First Search+1

Acceptance: 37.0%

#1037Easy

Valid Boomerang

ArrayGeometryMath

Acceptance: 39.9%

#1038Medium

Binary Search Tree to Greater Sum Tree

Binary Search TreeBinary TreeDepth-First Search+1

Acceptance: 88.3%

#1039Medium

Minimum Score Triangulation of Polygon

ArrayDynamic Programming

Acceptance: 67.4%

#1040Medium

Moving Stones Until Consecutive II

ArrayMathSorting+1

Acceptance: 59.4%

#1041Medium

Robot Bounded In Circle

MathSimulationString

Acceptance: 56.6%

#1042Medium

Flower Planting With No Adjacent

Breadth-First SearchDepth-First SearchGraph

Acceptance: 54.1%

#1043Medium

Partition Array for Maximum Sum

ArrayDynamic Programming

Acceptance: 77.4%

#1044Hard

Longest Duplicate Substring

Binary SearchHash FunctionRolling Hash+3

Acceptance: 31.1%

#1045Medium

Customers Who Bought All Products

Database

Acceptance: 62.6%

#1046Easy

Last Stone Weight

ArrayHeap (Priority Queue)

Acceptance: 66.4%

#1047Easy

Remove All Adjacent Duplicates In String

StackString

Acceptance: 73.6%

#1048Medium

Longest String Chain

ArrayDynamic ProgrammingHash Table+3

Acceptance: 63.5%

#1049Medium

Last Stone Weight II

ArrayDynamic Programming

Acceptance: 60.6%

#1050Easy

Actors and Directors Who Cooperated At Least Three Times

Database

Acceptance: 70.3%

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Master DSA with Step-by-Step Solutions

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