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
1101. The Earliest Moment When Everyone Become Friends	Medium	66.0%	Array Sorting+1	Read
1102. Path With Maximum Minimum Value	Medium	54.6%	Array Binary Search+5	Read
1103. Distribute Candies to People	Easy	67.5%	Math Simulation	Read
1104. Path In Zigzag Labelled Binary Tree	Medium	75.9%	Binary Tree Math+1	Read
1105. Filling Bookcase Shelves	Medium	68.7%	Array Dynamic Programming	Read
1106. Parsing A Boolean Expression	Hard	69.8%	Recursion Stack+1	Read
1107. New Users Daily Count	Medium	44.7%	Database	Read
1108. Defanging an IP Address	Easy	90.0%	String	Read
1109. Corporate Flight Bookings	Medium	68.7%	Array Prefix Sum	Read
1110. Delete Nodes And Return Forest	Medium	72.4%	Array Binary Tree+3	Read
1111. Maximum Nesting Depth of Two Valid Parentheses Strings	Medium	72.1%	Stack String	Read
1112. Highest Grade For Each Student	Medium	70.8%	Database	Read
1113. Reported Posts	Easy	65.0%	Database	Read
1114. Print in Order	Easy	70.3%	Concurrency	Read
1115. Print FooBar Alternately	Medium	67.7%	Concurrency	Read
1116. Print Zero Even Odd	Medium	62.0%	Concurrency	Read
1117. Building H2O	Medium	57.1%	Concurrency	Read
1118. Number of Days in a Month	Easy	59.4%	Math	Read
1119. Remove Vowels from a String	Easy	91.2%	String	Read
1120. Maximum Average Subtree	Medium	66.7%	Binary Tree Depth-First Search+1	Read
1121. Divide Array Into Increasing Sequences	Hard	65.4%	Array Counting	Read
1122. Relative Sort Array	Easy	75.4%	Array Counting Sort+2	Read
1123. Lowest Common Ancestor of Deepest Leaves	Medium	79.5%	Binary Tree Breadth-First Search+3	Read
1124. Longest Well-Performing Interval	Medium	37.9%	Array Hash Table+3	Read
1125. Smallest Sufficient Team	Hard	55.5%	Array Bit Manipulation+2	Read
1126. Active Businesses	Medium	65.8%	Database	Read
1127. User Purchase Platform	Hard	46.9%	Database	Read
1128. Number of Equivalent Domino Pairs	Easy	60.7%	Array Counting+1	Read
1129. Shortest Path with Alternating Colors	Medium	47.8%	Breadth-First Search Graph	Read
1130. Minimum Cost Tree From Leaf Values	Medium	67.7%	Array Dynamic Programming+3	Read
1131. Maximum of Absolute Value Expression	Medium	48.4%	Array Math	Read
1132. Reported Posts II	Medium	32.3%	Database	Read
1133. Largest Unique Number	Easy	71.3%	Array Hash Table+1	Read
1134. Armstrong Number	Easy	77.8%	Math	Read
1135. Connecting Cities With Minimum Cost	Medium	63.5%	Graph Heap (Priority Queue)+2	Read
1136. Parallel Courses	Medium	62.1%	Graph Topological Sort	Read
1137. N-th Tribonacci Number	Easy	63.2%	Dynamic Programming Math+1	Read
1138. Alphabet Board Path	Medium	51.5%	Hash Table String	Read
1139. Largest 1-Bordered Square	Medium	52.1%	Array Dynamic Programming+1	Read
1140. Stone Game II	Medium	75.8%	Array Dynamic Programming+3	Read
1141. User Activity for the Past 30 Days I	Easy	49.2%	Database	Read
1142. User Activity for the Past 30 Days II	Easy	35.7%	Database	Read
1143. Longest Common Subsequence	Medium	59.6%	Dynamic Programming String	Read
1144. Decrease Elements To Make Array Zigzag	Medium	49.7%	Array Greedy	Read
1145. Binary Tree Coloring Game	Medium	52.9%	Binary Tree Depth-First Search+1	Read
1146. Snapshot Array	Medium	36.8%	Array Binary Search+2	Read
1147. Longest Chunked Palindrome Decomposition	Hard	58.6%	Dynamic Programming Greedy+4	Read
1148. Article Views I	Easy	76.8%	Database	Read
1149. Article Views II	Medium	47.1%	Database	Read
1150. Check If a Number Is Majority Element in a Sorted Array	Easy	59.9%	Array Binary Search	Read

#1101Medium

The Earliest Moment When Everyone Become Friends

ArraySortingUnion Find

Acceptance: 66.0%

#1102Medium

Path With Maximum Minimum Value

ArrayBinary SearchBreadth-First Search+4

Acceptance: 54.6%

#1103Easy

Distribute Candies to People

MathSimulation

Acceptance: 67.5%

#1104Medium

Path In Zigzag Labelled Binary Tree

Binary TreeMathTree

Acceptance: 75.9%

#1105Medium

Filling Bookcase Shelves

ArrayDynamic Programming

Acceptance: 68.7%

#1106Hard

Parsing A Boolean Expression

RecursionStackString

Acceptance: 69.8%

#1107Medium

New Users Daily Count

Database

Acceptance: 44.7%

#1108Easy

Defanging an IP Address

String

Acceptance: 90.0%

#1109Medium

Corporate Flight Bookings

ArrayPrefix Sum

Acceptance: 68.7%

#1110Medium

Delete Nodes And Return Forest

ArrayBinary TreeDepth-First Search+2

Acceptance: 72.4%

#1111Medium

Maximum Nesting Depth of Two Valid Parentheses Strings

StackString

Acceptance: 72.1%

#1112Medium

Highest Grade For Each Student

Database

Acceptance: 70.8%

#1113Easy

Reported Posts

Database

Acceptance: 65.0%

#1114Easy

Print in Order

Concurrency

Acceptance: 70.3%

#1115Medium

Print FooBar Alternately

Concurrency

Acceptance: 67.7%

#1116Medium

Print Zero Even Odd

Concurrency

Acceptance: 62.0%

#1117Medium

Building H2O

Concurrency

Acceptance: 57.1%

#1118Easy

Number of Days in a Month

Math

Acceptance: 59.4%

#1119Easy

Remove Vowels from a String

String

Acceptance: 91.2%

#1120Medium

Maximum Average Subtree

Binary TreeDepth-First SearchTree

Acceptance: 66.7%

#1121Hard

Divide Array Into Increasing Sequences

ArrayCounting

Acceptance: 65.4%

#1122Easy

Relative Sort Array

ArrayCounting SortHash Table+1

Acceptance: 75.4%

#1123Medium

Lowest Common Ancestor of Deepest Leaves

Binary TreeBreadth-First SearchDepth-First Search+2

Acceptance: 79.5%

#1124Medium

Longest Well-Performing Interval

ArrayHash TableMonotonic Stack+2

Acceptance: 37.9%

#1125Hard

Smallest Sufficient Team

ArrayBit ManipulationBitmask+1

Acceptance: 55.5%

#1126Medium

Active Businesses

Database

Acceptance: 65.8%

#1127Hard

User Purchase Platform

Database

Acceptance: 46.9%

#1128Easy

Number of Equivalent Domino Pairs

ArrayCountingHash Table

Acceptance: 60.7%

#1129Medium

Shortest Path with Alternating Colors

Breadth-First SearchGraph

Acceptance: 47.8%

#1130Medium

Minimum Cost Tree From Leaf Values

ArrayDynamic ProgrammingGreedy+2

Acceptance: 67.7%

#1131Medium

Maximum of Absolute Value Expression

ArrayMath

Acceptance: 48.4%

#1132Medium

Reported Posts II

Database

Acceptance: 32.3%

#1133Easy

Largest Unique Number

ArrayHash TableSorting

Acceptance: 71.3%

#1134Easy

Armstrong Number

Math

Acceptance: 77.8%

#1135Medium

Connecting Cities With Minimum Cost

GraphHeap (Priority Queue)Minimum Spanning Tree+1

Acceptance: 63.5%

#1136Medium

Parallel Courses

GraphTopological Sort

Acceptance: 62.1%

#1137Easy

N-th Tribonacci Number

Dynamic ProgrammingMathMemoization

Acceptance: 63.2%

#1138Medium

Alphabet Board Path

Hash TableString

Acceptance: 51.5%

#1139Medium

Largest 1-Bordered Square

ArrayDynamic ProgrammingMatrix

Acceptance: 52.1%

#1140Medium

Stone Game II

ArrayDynamic ProgrammingGame Theory+2

Acceptance: 75.8%

#1141Easy

User Activity for the Past 30 Days I

Database

Acceptance: 49.2%

#1142Easy

User Activity for the Past 30 Days II

Database

Acceptance: 35.7%

#1143Medium

Longest Common Subsequence

Dynamic ProgrammingString

Acceptance: 59.6%

#1144Medium

Decrease Elements To Make Array Zigzag

ArrayGreedy

Acceptance: 49.7%

#1145Medium

Binary Tree Coloring Game

Binary TreeDepth-First SearchTree

Acceptance: 52.9%

#1146Medium

Snapshot Array

ArrayBinary SearchDesign+1

Acceptance: 36.8%

#1147Hard

Longest Chunked Palindrome Decomposition

Dynamic ProgrammingGreedyHash Function+3

Acceptance: 58.6%

#1148Easy

Article Views I

Database

Acceptance: 76.8%

#1149Medium

Article Views II

Database

Acceptance: 47.1%

#1150Easy

Check If a Number Is Majority Element in a Sorted Array

ArrayBinary Search

Acceptance: 59.9%

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Master DSA with Step-by-Step Solutions

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