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
3043. Find the Length of the Longest Common Prefix	Medium	62.1%	Array Hash Table+2	Read
3044. Most Frequent Prime	Medium	45.5%	Array Counting+5	Read
3047. Find the Largest Area of Square Inside Two Rectangles	Medium	66.9%	Array Geometry+1	Read
3048. Earliest Second to Mark Indices I	Medium	36.7%	Array Binary Search	Read
3050. Pizza Toppings Cost Analysis	Medium	66.2%	Database	Read
3054. Binary Tree Nodes	Medium	79.8%	Database	Read
3055. Top Percentile Fraud	Medium	58.1%	Database	Read
3056. Snaps Analysis	Medium	58.0%	Database	Read
3058. Friends With No Mutual Friends	Medium	49.4%	Database	Read
3064. Guess the Number Using Bitwise Questions I	Medium	89.0%	Bit Manipulation Interactive	Read
3066. Minimum Operations to Exceed Threshold Value II	Medium	45.8%	Array Heap (Priority Queue)+1	Read
3067. Count Pairs of Connectable Servers in a Weighted Tree Network	Medium	55.6%	Array Depth-First Search+1	Read
3070. Count Submatrices with Top-Left Element and Sum Less Than k	Medium	74.8%	Array Matrix+1	Read
3071. Minimum Operations to Write the Letter Y on a Grid	Medium	63.9%	Array Counting+2	Read
3073. Maximum Increasing Triplet Value	Medium	35.7%	Array Ordered Set	Read
3075. Maximize Happiness of Selected Children	Medium	58.7%	Array Greedy+1	Read
3076. Shortest Uncommon Substring in an Array	Medium	50.8%	Array Hash Table+2	Read
3078. Match Alphanumerical Pattern in Matrix I	Medium	64.6%	Array Hash Table+2	Read
3080. Mark Elements on Array by Performing Queries	Medium	49.1%	Array Hash Table+3	Read
3081. Replace Question Marks in String to Minimize Its Value	Medium	29.0%	Counting Greedy+4	Read
3084. Count Substrings Starting and Ending with Given Character	Medium	49.9%	Counting Math+1	Read
3085. Minimum Deletions to Make String K-Special	Medium	67.2%	Counting Greedy+3	Read
3087. Find Trending Hashtags	Medium	62.0%	Database	Read
3089. Find Bursty Behavior	Medium	39.4%	Database	Read
3091. Apply Operations to Make Sum of Array Greater Than or Equal to k	Medium	44.2%	Enumeration Greedy+1	Read
3092. Most Frequent IDs	Medium	43.0%	Array Hash Table+2	Read
3094. Guess the Number Using Bitwise Questions II	Medium	83.0%	Bit Manipulation Interactive	Read
3096. Minimum Levels to Gain More Points	Medium	40.4%	Array Prefix Sum	Read
3097. Shortest Subarray With OR at Least K II	Medium	50.5%	Array Bit Manipulation+1	Read
3100. Water Bottles II	Medium	78.2%	Math Simulation	Read
3101. Count Alternating Subarrays	Medium	57.6%	Array Math	Read
3106. Lexicographically Smallest String After Operations With Constraint	Medium	62.3%	Greedy String	Read
3107. Minimum Operations to Make Median of Array Equal to K	Medium	47.7%	Array Greedy+1	Read
3109. Find the Index of Permutation	Medium	37.1%	Array Binary Indexed Tree+5	Read
3111. Minimum Rectangles to Cover Points	Medium	63.2%	Array Greedy+1	Read
3112. Minimum Time to Visit Disappearing Nodes	Medium	38.2%	Array Graph+2	Read
3115. Maximum Prime Difference	Medium	59.3%	Array Math+1	Read
3118. Friday Purchase III	Medium	58.0%	Database	Read
3119. Maximum Number of Potholes That Can Be Fixed	Medium	53.3%	Greedy Sorting+1	Read
3121. Count the Number of Special Characters II	Medium	60.3%	Hash Table String	Read
3122. Minimum Number of Operations to Satisfy Conditions	Medium	42.4%	Array Dynamic Programming+1	Read
3124. Find Longest Calls	Medium	62.6%	Database	Read
3125. Maximum Number That Makes Result of Bitwise AND Zero	Medium	70.0%	Greedy Sorting+1	Read
3126. Server Utilization Time	Medium	60.3%	Database	Read
3128. Right Triangles	Medium	48.5%	Array Combinatorics+3	Read
3129. Find All Possible Stable Binary Arrays I	Medium	53.8%	Dynamic Programming Prefix Sum	Read
3132. Find the Integer Added to Array II	Medium	32.9%	Array Enumeration+2	Read
3133. Minimum Array End	Medium	55.5%	Bit Manipulation	Read
3135. Equalize Strings by Adding or Removing Characters at Ends	Medium	56.8%	Binary Search Dynamic Programming+3	Read
3137. Minimum Number of Operations to Make Word K-Periodic	Medium	59.9%	Counting Hash Table+1	Read

#3043Medium

Find the Length of the Longest Common Prefix

ArrayHash TableString+1

Acceptance: 62.1%

#3044Medium

Most Frequent Prime

ArrayCountingEnumeration+4

Acceptance: 45.5%

#3047Medium

Find the Largest Area of Square Inside Two Rectangles

ArrayGeometryMath

Acceptance: 66.9%

#3048Medium

Earliest Second to Mark Indices I

ArrayBinary Search

Acceptance: 36.7%

#3050Medium

Pizza Toppings Cost Analysis

Database

Acceptance: 66.2%

#3054Medium

Binary Tree Nodes

Database

Acceptance: 79.8%

#3055Medium

Top Percentile Fraud

Database

Acceptance: 58.1%

#3056Medium

Snaps Analysis

Database

Acceptance: 58.0%

#3058Medium

Friends With No Mutual Friends

Database

Acceptance: 49.4%

#3064Medium

Guess the Number Using Bitwise Questions I

Bit ManipulationInteractive

Acceptance: 89.0%

#3066Medium

Minimum Operations to Exceed Threshold Value II

ArrayHeap (Priority Queue)Simulation

Acceptance: 45.8%

#3067Medium

Count Pairs of Connectable Servers in a Weighted Tree Network

ArrayDepth-First SearchTree

Acceptance: 55.6%

#3070Medium

Count Submatrices with Top-Left Element and Sum Less Than k

ArrayMatrixPrefix Sum

Acceptance: 74.8%

#3071Medium

Minimum Operations to Write the Letter Y on a Grid

ArrayCountingHash Table+1

Acceptance: 63.9%

#3073Medium

Maximum Increasing Triplet Value

ArrayOrdered Set

Acceptance: 35.7%

#3075Medium

Maximize Happiness of Selected Children

ArrayGreedySorting

Acceptance: 58.7%

#3076Medium

Shortest Uncommon Substring in an Array

ArrayHash TableString+1

Acceptance: 50.8%

#3078Medium

Match Alphanumerical Pattern in Matrix I

ArrayHash TableMatrix+1

Acceptance: 64.6%

#3080Medium

Mark Elements on Array by Performing Queries

ArrayHash TableHeap (Priority Queue)+2

Acceptance: 49.1%

#3081Medium

Replace Question Marks in String to Minimize Its Value

CountingGreedyHash Table+3

Acceptance: 29.0%

#3084Medium

Count Substrings Starting and Ending with Given Character

CountingMathString

Acceptance: 49.9%

#3085Medium

Minimum Deletions to Make String K-Special

CountingGreedyHash Table+2

Acceptance: 67.2%

#3087Medium

Find Trending Hashtags

Database

Acceptance: 62.0%

#3089Medium

Find Bursty Behavior

Database

Acceptance: 39.4%

#3091Medium

Apply Operations to Make Sum of Array Greater Than or Equal to k

EnumerationGreedyMath

Acceptance: 44.2%

#3092Medium

Most Frequent IDs

ArrayHash TableHeap (Priority Queue)+1

Acceptance: 43.0%

#3094Medium

Guess the Number Using Bitwise Questions II

Bit ManipulationInteractive

Acceptance: 83.0%

#3096Medium

Minimum Levels to Gain More Points

ArrayPrefix Sum

Acceptance: 40.4%

#3097Medium

Shortest Subarray With OR at Least K II

ArrayBit ManipulationSliding Window

Acceptance: 50.5%

#3100Medium

Water Bottles II

MathSimulation

Acceptance: 78.2%

#3101Medium

Count Alternating Subarrays

ArrayMath

Acceptance: 57.6%

#3106Medium

Lexicographically Smallest String After Operations With Constraint

GreedyString

Acceptance: 62.3%

#3107Medium

Minimum Operations to Make Median of Array Equal to K

ArrayGreedySorting

Acceptance: 47.7%

#3109Medium

Find the Index of Permutation

ArrayBinary Indexed TreeBinary Search+4

Acceptance: 37.1%

#3111Medium

Minimum Rectangles to Cover Points

ArrayGreedySorting

Acceptance: 63.2%

#3112Medium

Minimum Time to Visit Disappearing Nodes

ArrayGraphHeap (Priority Queue)+1

Acceptance: 38.2%

#3115Medium

Maximum Prime Difference

ArrayMathNumber Theory

Acceptance: 59.3%

#3118Medium

Friday Purchase III

Database

Acceptance: 58.0%

#3119Medium

Maximum Number of Potholes That Can Be Fixed

GreedySortingString

Acceptance: 53.3%

#3121Medium

Count the Number of Special Characters II

Hash TableString

Acceptance: 60.3%

#3122Medium

Minimum Number of Operations to Satisfy Conditions

ArrayDynamic ProgrammingMatrix

Acceptance: 42.4%

#3124Medium

Find Longest Calls

Database

Acceptance: 62.6%

#3125Medium

Maximum Number That Makes Result of Bitwise AND Zero

GreedySortingString

Acceptance: 70.0%

#3126Medium

Server Utilization Time

Database

Acceptance: 60.3%

#3128Medium

Right Triangles

ArrayCombinatoricsCounting+2

Acceptance: 48.5%

#3129Medium

Find All Possible Stable Binary Arrays I

Dynamic ProgrammingPrefix Sum

Acceptance: 53.8%

#3132Medium

Find the Integer Added to Array II

ArrayEnumerationSorting+1

Acceptance: 32.9%

#3133Medium

Minimum Array End

Bit Manipulation

Acceptance: 55.5%

#3135Medium

Equalize Strings by Adding or Removing Characters at Ends

Binary SearchDynamic ProgrammingHash Function+2

Acceptance: 56.8%

#3137Medium

Minimum Number of Operations to Make Word K-Periodic

CountingHash TableString

Acceptance: 59.9%

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