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
988. Smallest String Starting From Leaf	Medium	61.2%	Backtracking Binary Tree+3	Read
990. Satisfiability of Equality Equations	Medium	52.2%	Array Graph+2	Read
991. Broken Calculator	Medium	56.0%	Greedy Math	Read
994. Rotting Oranges	Medium	59.5%	Array Breadth-First Search+1	Read
998. Maximum Binary Tree II	Medium	70.8%	Binary Tree Tree	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
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
1010. Pairs of Songs With Total Durations Divisible by 60	Medium	53.6%	Array Counting+1	Read
1011. Capacity To Ship Packages Within D Days	Medium	74.2%	Array Binary Search	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
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
1023. Camelcase Matching	Medium	65.8%	Array String+3	Read
1024. Video Stitching	Medium	52.6%	Array Dynamic Programming+1	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
1029. Two City Scheduling	Medium	69.0%	Array Greedy+1	Read
1031. Maximum Sum of Two Non-Overlapping Subarrays	Medium	61.4%	Array Dynamic Programming+1	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
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
1045. Customers Who Bought All Products	Medium	62.6%	Database	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
1052. Grumpy Bookstore Owner	Medium	64.2%	Array Sliding Window	Read
1053. Previous Permutation With One Swap	Medium	49.5%	Array Greedy	Read
1054. Distant Barcodes	Medium	49.3%	Array Counting+4	Read
1055. Shortest Way to Form String	Medium	61.6%	Binary Search Greedy+2	Read
1057. Campus Bikes	Medium	58.8%	Array Greedy+1	Read
1058. Minimize Rounding Error to Meet Target	Medium	45.9%	Array Greedy+3	Read
1059. All Paths from Source Lead to Destination	Medium	37.2%	Graph Topological Sort	Read
1060. Missing Element in Sorted Array	Medium	59.7%	Array Binary Search	Read
1061. Lexicographically Smallest Equivalent String	Medium	81.1%	String Union Find	Read
1062. Longest Repeating Substring	Medium	63.4%	Binary Search Dynamic Programming+4	Read
1066. Campus Bikes II	Medium	55.9%	Array Backtracking+3	Read
1070. Product Sales Analysis III	Medium	44.3%	Database	Read
1072. Flip Columns For Maximum Number of Equal Rows	Medium	78.5%	Array Hash Table+1	Read
1073. Adding Two Negabinary Numbers	Medium	37.7%	Array Math	Read

#988Medium

Smallest String Starting From Leaf

BacktrackingBinary TreeDepth-First Search+2

Acceptance: 61.2%

#990Medium

Satisfiability of Equality Equations

ArrayGraphString+1

Acceptance: 52.2%

#991Medium

Broken Calculator

GreedyMath

Acceptance: 56.0%

#994Medium

Rotting Oranges

ArrayBreadth-First SearchMatrix

Acceptance: 59.5%

#998Medium

Maximum Binary Tree II

Binary TreeTree

Acceptance: 70.8%

#1003Medium

Check If Word Is Valid After Substitutions

StackString

Acceptance: 61.1%

#1004Medium

Max Consecutive Ones III

ArrayBinary SearchPrefix Sum+1

Acceptance: 68.0%

#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%

#1010Medium

Pairs of Songs With Total Durations Divisible by 60

ArrayCountingHash Table

Acceptance: 53.6%

#1011Medium

Capacity To Ship Packages Within D Days

ArrayBinary Search

Acceptance: 74.2%

#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%

#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%

#1023Medium

Camelcase Matching

ArrayStringString Matching+2

Acceptance: 65.8%

#1024Medium

Video Stitching

ArrayDynamic ProgrammingGreedy

Acceptance: 52.6%

#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%

#1029Medium

Two City Scheduling

ArrayGreedySorting

Acceptance: 69.0%

#1031Medium

Maximum Sum of Two Non-Overlapping Subarrays

ArrayDynamic ProgrammingSliding Window

Acceptance: 61.4%

#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%

#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%

#1045Medium

Customers Who Bought All Products

Database

Acceptance: 62.6%

#1048Medium

Longest String Chain

ArrayDynamic ProgrammingHash Table+3

Acceptance: 63.5%

#1049Medium

Last Stone Weight II

ArrayDynamic Programming

Acceptance: 60.6%

#1052Medium

Grumpy Bookstore Owner

ArraySliding Window

Acceptance: 64.2%

#1053Medium

Previous Permutation With One Swap

ArrayGreedy

Acceptance: 49.5%

#1054Medium

Distant Barcodes

ArrayCountingGreedy+3

Acceptance: 49.3%

#1055Medium

Shortest Way to Form String

Binary SearchGreedyString+1

Acceptance: 61.6%

#1057Medium

Campus Bikes

ArrayGreedySorting

Acceptance: 58.8%

#1058Medium

Minimize Rounding Error to Meet Target

ArrayGreedyMath+2

Acceptance: 45.9%

#1059Medium

All Paths from Source Lead to Destination

GraphTopological Sort

Acceptance: 37.2%

#1060Medium

Missing Element in Sorted Array

ArrayBinary Search

Acceptance: 59.7%

#1061Medium

Lexicographically Smallest Equivalent String

StringUnion Find

Acceptance: 81.1%

#1062Medium

Longest Repeating Substring

Binary SearchDynamic ProgrammingHash Function+3

Acceptance: 63.4%

#1066Medium

Campus Bikes II

ArrayBacktrackingBit Manipulation+2

Acceptance: 55.9%

#1070Medium

Product Sales Analysis III

Database

Acceptance: 44.3%

#1072Medium

Flip Columns For Maximum Number of Equal Rows

ArrayHash TableMatrix

Acceptance: 78.5%

#1073Medium

Adding Two Negabinary Numbers

ArrayMath

Acceptance: 37.7%

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