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
1051. Height Checker	Easy	81.6%	Array Counting Sort+1	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
1056. Confusing Number	Easy	49.8%	Math	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
1063. Number of Valid Subarrays	Hard	79.9%	Array Monotonic Stack+1	Read
1064. Fixed Point	Easy	64.1%	Array Binary Search	Read
1065. Index Pairs of a String	Easy	68.6%	Array Sorting+2	Read
1066. Campus Bikes II	Medium	55.9%	Array Backtracking+3	Read
1067. Digit Count in Range	Hard	46.4%	Dynamic Programming Math	Read
1068. Product Sales Analysis I	Easy	85.3%	Database	Read
1069. Product Sales Analysis II	Easy	82.1%	Database	Read
1070. Product Sales Analysis III	Medium	44.3%	Database	Read
1071. Greatest Common Divisor of Strings	Easy	54.1%	Math String	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
1074. Number of Submatrices That Sum to Target	Hard	74.4%	Array Hash Table+2	Read
1075. Project Employees I	Easy	64.2%	Database	Read
1076. Project Employees II	Easy	50.1%	Database	Read
1077. Project Employees III	Medium	76.8%	Database	Read
1078. Occurrences After Bigram	Easy	64.1%	String	Read
1079. Letter Tile Possibilities	Medium	83.5%	Backtracking Counting+2	Read
1080. Insufficient Nodes in Root to Leaf Paths	Medium	55.6%	Binary Tree Depth-First Search+1	Read
1081. Smallest Subsequence of Distinct Characters	Medium	70.6%	Greedy Monotonic Stack+2	Read
1082. Sales Analysis I	Easy	74.6%	Database	Read
1083. Sales Analysis II	Easy	49.8%	Database	Read
1084. Sales Analysis III	Easy	46.8%	Database	Read
1085. Sum of Digits in the Minimum Number	Easy	76.6%	Array Math	Read
1086. High Five	Easy	74.5%	Array Hash Table+2	Read
1087. Brace Expansion	Medium	66.5%	Backtracking Breadth-First Search+1	Read
1088. Confusing Number II	Hard	47.1%	Backtracking Math	Read
1089. Duplicate Zeros	Easy	54.1%	Array Two Pointers	Read
1090. Largest Values From Labels	Medium	64.7%	Array Counting+3	Read
1091. Shortest Path in Binary Matrix	Medium	51.8%	Array Breadth-First Search+1	Read
1092. Shortest Common Supersequence	Hard	61.8%	Dynamic Programming String	Read
1093. Statistics from a Large Sample	Medium	43.6%	Array Math+1	Read
1094. Car Pooling	Medium	56.5%	Array Heap (Priority Queue)+3	Read
1095. Find in Mountain Array	Hard	41.9%	Array Binary Search+1	Read
1096. Brace Expansion II	Hard	64.0%	Backtracking Breadth-First Search+2	Read
1097. Game Play Analysis V	Hard	50.8%	Database	Read
1098. Unpopular Books	Medium	43.3%	Database	Read
1099. Two Sum Less Than K	Easy	61.9%	Array Binary Search+2	Read
1100. Find K-Length Substrings With No Repeated Characters	Medium	76.5%	Hash Table Sliding Window+1	Read

#1051Easy

Height Checker

ArrayCounting SortSorting

Acceptance: 81.6%

#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%

#1056Easy

Confusing Number

Math

Acceptance: 49.8%

#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%

#1063Hard

Number of Valid Subarrays

ArrayMonotonic StackStack

Acceptance: 79.9%

#1064Easy

Fixed Point

ArrayBinary Search

Acceptance: 64.1%

#1065Easy

Index Pairs of a String

ArraySortingString+1

Acceptance: 68.6%

#1066Medium

Campus Bikes II

ArrayBacktrackingBit Manipulation+2

Acceptance: 55.9%

#1067Hard

Digit Count in Range

Dynamic ProgrammingMath

Acceptance: 46.4%

#1068Easy

Product Sales Analysis I

Database

Acceptance: 85.3%

#1069Easy

Product Sales Analysis II

Database

Acceptance: 82.1%

#1070Medium

Product Sales Analysis III

Database

Acceptance: 44.3%

#1071Easy

Greatest Common Divisor of Strings

MathString

Acceptance: 54.1%

#1072Medium

Flip Columns For Maximum Number of Equal Rows

ArrayHash TableMatrix

Acceptance: 78.5%

#1073Medium

Adding Two Negabinary Numbers

ArrayMath

Acceptance: 37.7%

#1074Hard

Number of Submatrices That Sum to Target

ArrayHash TableMatrix+1

Acceptance: 74.4%

#1075Easy

Project Employees I

Database

Acceptance: 64.2%

#1076Easy

Project Employees II

Database

Acceptance: 50.1%

#1077Medium

Project Employees III

Database

Acceptance: 76.8%

#1078Easy

Occurrences After Bigram

String

Acceptance: 64.1%

#1079Medium

Letter Tile Possibilities

BacktrackingCountingHash Table+1

Acceptance: 83.5%

#1080Medium

Insufficient Nodes in Root to Leaf Paths

Binary TreeDepth-First SearchTree

Acceptance: 55.6%

#1081Medium

Smallest Subsequence of Distinct Characters

GreedyMonotonic StackStack+1

Acceptance: 70.6%

#1082Easy

Sales Analysis I

Database

Acceptance: 74.6%

#1083Easy

Sales Analysis II

Database

Acceptance: 49.8%

#1084Easy

Sales Analysis III

Database

Acceptance: 46.8%

#1085Easy

Sum of Digits in the Minimum Number

ArrayMath

Acceptance: 76.6%

#1086Easy

High Five

ArrayHash TableHeap (Priority Queue)+1

Acceptance: 74.5%

#1087Medium

Brace Expansion

BacktrackingBreadth-First SearchString

Acceptance: 66.5%

#1088Hard

Confusing Number II

BacktrackingMath

Acceptance: 47.1%

#1089Easy

Duplicate Zeros

ArrayTwo Pointers

Acceptance: 54.1%

#1090Medium

Largest Values From Labels

ArrayCountingGreedy+2

Acceptance: 64.7%

#1091Medium

Shortest Path in Binary Matrix

ArrayBreadth-First SearchMatrix

Acceptance: 51.8%

#1092Hard

Shortest Common Supersequence

Dynamic ProgrammingString

Acceptance: 61.8%

#1093Medium

Statistics from a Large Sample

ArrayMathProbability and Statistics

Acceptance: 43.6%

#1094Medium

Car Pooling

ArrayHeap (Priority Queue)Prefix Sum+2

Acceptance: 56.5%

#1095Hard

Find in Mountain Array

ArrayBinary SearchInteractive

Acceptance: 41.9%

#1096Hard

Brace Expansion II

BacktrackingBreadth-First SearchStack+1

Acceptance: 64.0%

#1097Hard

Game Play Analysis V

Database

Acceptance: 50.8%

#1098Medium

Unpopular Books

Database

Acceptance: 43.3%

#1099Easy

Two Sum Less Than K

ArrayBinary SearchSorting+1

Acceptance: 61.9%

#1100Medium

Find K-Length Substrings With No Repeated Characters

Hash TableSliding WindowString

Acceptance: 76.5%

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