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
3101. Count Alternating Subarrays	Medium	57.6%	Array Math	Read
3102. Minimize Manhattan Distances	Hard	32.9%	Array Geometry+3	Read
3103. Find Trending Hashtags II	Hard	64.7%	Database	Read
3104. Find Longest Self-Contained Substring	Hard	58.6%	Binary Search Hash Table+2	Read
3105. Longest Strictly Increasing or Strictly Decreasing Subarray	Easy	64.9%	Array	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
3108. Minimum Cost Walk in Weighted Graph	Hard	68.3%	Array Bit Manipulation+2	Read
3109. Find the Index of Permutation	Medium	37.1%	Array Binary Indexed Tree+5	Read
3110. Score of a String	Easy	91.4%	String	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
3113. Find the Number of Subarrays Where Boundary Elements Are Maximum	Hard	34.2%	Array Binary Search+2	Read
3114. Latest Time You Can Obtain After Replacing Characters	Easy	35.4%	Enumeration String	Read
3115. Maximum Prime Difference	Medium	59.3%	Array Math+1	Read
3116. Kth Smallest Amount With Single Denomination Combination	Hard	50.3%	Array Binary Search+4	Read
3117. Minimum Sum of Values by Dividing Array	Hard	27.9%	Array Binary Search+4	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
3120. Count the Number of Special Characters I	Easy	77.2%	Hash Table String	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
3123. Find Edges in Shortest Paths	Hard	47.0%	Breadth-First Search Depth-First Search+3	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
3127. Make a Square with the Same Color	Easy	53.0%	Array Enumeration+1	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
3130. Find All Possible Stable Binary Arrays II	Hard	58.4%	Dynamic Programming Prefix Sum	Read
3131. Find the Integer Added to Array I	Easy	82.9%	Array	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
3134. Find the Median of the Uniqueness Array	Hard	30.0%	Array Binary Search+2	Read
3135. Equalize Strings by Adding or Removing Characters at Ends	Medium	56.8%	Binary Search Dynamic Programming+3	Read
3136. Valid Word	Easy	50.9%	String	Read
3137. Minimum Number of Operations to Make Word K-Periodic	Medium	59.9%	Counting Hash Table+1	Read
3138. Minimum Length of Anagram Concatenation	Medium	39.8%	Counting Hash Table+1	Read
3139. Minimum Cost to Equalize Array	Hard	18.8%	Array Enumeration+1	Read
3140. Consecutive Available Seats II	Medium	58.6%	Database	Read
3141. Maximum Hamming Distances	Hard	50.0%	Array Bit Manipulation+1	Read
3142. Check if Grid Satisfies Conditions	Easy	45.7%	Array Matrix	Read
3143. Maximum Points Inside the Square	Medium	39.9%	Array Binary Search+3	Read
3144. Minimum Substring Partition of Equal Character Frequency	Medium	40.5%	Counting Dynamic Programming+2	Read
3145. Find Products of Elements of Big Array	Hard	24.4%	Array Binary Search+1	Read
3146. Permutation Difference between Two Strings	Easy	87.9%	Hash Table String	Read
3147. Taking Maximum Energy From the Mystic Dungeon	Medium	61.0%	Array Prefix Sum	Read
3148. Maximum Difference Score in a Grid	Medium	48.4%	Array Dynamic Programming+1	Read
3149. Find the Minimum Cost Array Permutation	Hard	26.1%	Array Bit Manipulation+2	Read
3150. Invalid Tweets II	Easy	87.0%	Database	Read

#3101Medium

Count Alternating Subarrays

ArrayMath

Acceptance: 57.6%

#3102Hard

Minimize Manhattan Distances

ArrayGeometryMath+2

Acceptance: 32.9%

#3103Hard

Find Trending Hashtags II

Database

Acceptance: 64.7%

#3104Hard

Find Longest Self-Contained Substring

Binary SearchHash TablePrefix Sum+1

Acceptance: 58.6%

#3105Easy

Longest Strictly Increasing or Strictly Decreasing Subarray

Array

Acceptance: 64.9%

#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%

#3108Hard

Minimum Cost Walk in Weighted Graph

ArrayBit ManipulationGraph+1

Acceptance: 68.3%

#3109Medium

Find the Index of Permutation

ArrayBinary Indexed TreeBinary Search+4

Acceptance: 37.1%

#3110Easy

Score of a String

String

Acceptance: 91.4%

#3111Medium

Minimum Rectangles to Cover Points

ArrayGreedySorting

Acceptance: 63.2%

#3112Medium

Minimum Time to Visit Disappearing Nodes

ArrayGraphHeap (Priority Queue)+1

Acceptance: 38.2%

#3113Hard

Find the Number of Subarrays Where Boundary Elements Are Maximum

ArrayBinary SearchMonotonic Stack+1

Acceptance: 34.2%

#3114Easy

Latest Time You Can Obtain After Replacing Characters

EnumerationString

Acceptance: 35.4%

#3115Medium

Maximum Prime Difference

ArrayMathNumber Theory

Acceptance: 59.3%

#3116Hard

Kth Smallest Amount With Single Denomination Combination

ArrayBinary SearchBit Manipulation+3

Acceptance: 50.3%

#3117Hard

Minimum Sum of Values by Dividing Array

ArrayBinary SearchBit Manipulation+3

Acceptance: 27.9%

#3118Medium

Friday Purchase III

Database

Acceptance: 58.0%

#3119Medium

Maximum Number of Potholes That Can Be Fixed

GreedySortingString

Acceptance: 53.3%

#3120Easy

Count the Number of Special Characters I

Hash TableString

Acceptance: 77.2%

#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%

#3123Hard

Find Edges in Shortest Paths

Breadth-First SearchDepth-First SearchGraph+2

Acceptance: 47.0%

#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%

#3127Easy

Make a Square with the Same Color

ArrayEnumerationMatrix

Acceptance: 53.0%

#3128Medium

Right Triangles

ArrayCombinatoricsCounting+2

Acceptance: 48.5%

#3129Medium

Find All Possible Stable Binary Arrays I

Dynamic ProgrammingPrefix Sum

Acceptance: 53.8%

#3130Hard

Find All Possible Stable Binary Arrays II

Dynamic ProgrammingPrefix Sum

Acceptance: 58.4%

#3131Easy

Find the Integer Added to Array I

Array

Acceptance: 82.9%

#3132Medium

Find the Integer Added to Array II

ArrayEnumerationSorting+1

Acceptance: 32.9%

#3133Medium

Minimum Array End

Bit Manipulation

Acceptance: 55.5%

#3134Hard

Find the Median of the Uniqueness Array

ArrayBinary SearchHash Table+1

Acceptance: 30.0%

#3135Medium

Equalize Strings by Adding or Removing Characters at Ends

Binary SearchDynamic ProgrammingHash Function+2

Acceptance: 56.8%

#3136Easy

Valid Word

String

Acceptance: 50.9%

#3137Medium

Minimum Number of Operations to Make Word K-Periodic

CountingHash TableString

Acceptance: 59.9%

#3138Medium

Minimum Length of Anagram Concatenation

CountingHash TableString

Acceptance: 39.8%

#3139Hard

Minimum Cost to Equalize Array

ArrayEnumerationGreedy

Acceptance: 18.8%

#3140Medium

Consecutive Available Seats II

Database

Acceptance: 58.6%

#3141Hard

Maximum Hamming Distances

ArrayBit ManipulationBreadth-First Search

Acceptance: 50.0%

#3142Easy

Check if Grid Satisfies Conditions

ArrayMatrix

Acceptance: 45.7%

#3143Medium

Maximum Points Inside the Square

ArrayBinary SearchHash Table+2

Acceptance: 39.9%

#3144Medium

Minimum Substring Partition of Equal Character Frequency

CountingDynamic ProgrammingHash Table+1

Acceptance: 40.5%

#3145Hard

Find Products of Elements of Big Array

ArrayBinary SearchBit Manipulation

Acceptance: 24.4%

#3146Easy

Permutation Difference between Two Strings

Hash TableString

Acceptance: 87.9%

#3147Medium

Taking Maximum Energy From the Mystic Dungeon

ArrayPrefix Sum

Acceptance: 61.0%

#3148Medium

Maximum Difference Score in a Grid

ArrayDynamic ProgrammingMatrix

Acceptance: 48.4%

#3149Hard

Find the Minimum Cost Array Permutation

ArrayBit ManipulationBitmask+1

Acceptance: 26.1%

#3150Easy

Invalid Tweets II

Database

Acceptance: 87.0%

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