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
2965. Find Missing and Repeated Values	Easy	83.2%	Array Hash Table+2	Read
2970. Count the Number of Incremovable Subarrays I	Easy	56.9%	Array Binary Search+2	Read
2974. Minimum Number Game	Easy	85.5%	Array Heap (Priority Queue)+2	Read
2980. Check if Bitwise OR Has Trailing Zeros	Easy	71.2%	Array Bit Manipulation	Read
2985. Calculate Compressed Mean	Easy	88.0%	Database	Read
2987. Find Expensive Cities	Easy	79.6%	Database	Read
2990. Loan Types	Easy	63.2%	Database	Read
2996. Smallest Missing Integer Greater Than Sequential Prefix Sum	Easy	49.8%	Array Hash Table+1	Read
3000. Maximum Area of Longest Diagonal Rectangle	Easy	45.9%	Array	Read
3005. Count Elements With Maximum Frequency	Easy	79.8%	Array Counting+1	Read
3010. Divide an Array Into Subarrays With Minimum Cost I	Easy	80.5%	Array Enumeration+1	Read
3014. Minimum Number of Pushes to Type Word I	Easy	77.1%	Greedy Math+1	Read
3019. Number of Changing Keys	Easy	80.6%	String	Read
3024. Type of Triangle	Easy	44.1%	Array Math+1	Read
3028. Ant on the Boundary	Easy	74.6%	Array Prefix Sum+1	Read
3032. Count Numbers With Unique Digits II	Easy	87.4%	Dynamic Programming Hash Table+1	Read
3033. Modify the Matrix	Easy	69.1%	Array Matrix	Read
3038. Maximum Number of Operations With the Same Score I	Easy	52.8%	Array Simulation	Read
3042. Count Prefix and Suffix Pairs I	Easy	77.8%	Array Hash Function+4	Read
3046. Split the Array	Easy	61.7%	Array Counting+1	Read
3051. Find Candidates for Data Scientist Position	Easy	74.7%	Database	Read
3053. Classifying Triangles by Lengths	Easy	50.3%	Database	Read
3059. Find All Unique Email Domains	Easy	69.0%	Database	Read
3062. Winner of the Linked List Game	Easy	77.6%	Linked List	Read
3063. Linked List Frequency	Easy	85.8%	Counting Hash Table+1	Read
3065. Minimum Operations to Exceed Threshold Value I	Easy	86.7%	Array	Read
3069. Distribute Elements Into Two Arrays I	Easy	83.4%	Array Simulation	Read
3074. Apple Redistribution into Boxes	Easy	78.5%	Array Greedy+1	Read
3079. Find the Sum of Encrypted Integers	Easy	74.7%	Array Math	Read
3083. Existence of a Substring in a String and Its Reverse	Easy	66.6%	Hash Table String	Read
3090. Maximum Length Substring With Two Occurrences	Easy	77.4%	Hash Table Sliding Window+1	Read
3095. Shortest Subarray With OR at Least K I	Easy	44.9%	Array Bit Manipulation+1	Read
3099. Harshad Number	Easy	83.4%	Math	Read
3105. Longest Strictly Increasing or Strictly Decreasing Subarray	Easy	64.9%	Array	Read
3110. Score of a String	Easy	91.4%	String	Read
3114. Latest Time You Can Obtain After Replacing Characters	Easy	35.4%	Enumeration String	Read
3120. Count the Number of Special Characters I	Easy	77.2%	Hash Table String	Read
3127. Make a Square with the Same Color	Easy	53.0%	Array Enumeration+1	Read
3131. Find the Integer Added to Array I	Easy	82.9%	Array	Read
3136. Valid Word	Easy	50.9%	String	Read
3142. Check if Grid Satisfies Conditions	Easy	45.7%	Array Matrix	Read
3146. Permutation Difference between Two Strings	Easy	87.9%	Hash Table String	Read
3150. Invalid Tweets II	Easy	87.0%	Database	Read
3151. Special Array I	Easy	81.6%	Array	Read
3158. Find the XOR of Numbers Which Appear Twice	Easy	78.9%	Array Bit Manipulation+1	Read
3162. Find the Number of Good Pairs I	Easy	86.4%	Array Hash Table	Read
3168. Minimum Number of Chairs in a Waiting Room	Easy	79.3%	Simulation String	Read
3172. Second Day Verification	Easy	70.7%	Database	Read
3173. Bitwise OR of Adjacent Elements	Easy	94.8%	Array Bit Manipulation	Read
3174. Clear Digits	Easy	82.7%	Simulation Stack+1	Read

#2965Easy

Find Missing and Repeated Values

ArrayHash TableMath+1

Acceptance: 83.2%

#2970Easy

Count the Number of Incremovable Subarrays I

ArrayBinary SearchEnumeration+1

Acceptance: 56.9%

#2974Easy

Minimum Number Game

ArrayHeap (Priority Queue)Simulation+1

Acceptance: 85.5%

#2980Easy

Check if Bitwise OR Has Trailing Zeros

ArrayBit Manipulation

Acceptance: 71.2%

#2985Easy

Calculate Compressed Mean

Database

Acceptance: 88.0%

#2987Easy

Find Expensive Cities

Database

Acceptance: 79.6%

#2990Easy

Loan Types

Database

Acceptance: 63.2%

#2996Easy

Smallest Missing Integer Greater Than Sequential Prefix Sum

ArrayHash TableSorting

Acceptance: 49.8%

#3000Easy

Maximum Area of Longest Diagonal Rectangle

Array

Acceptance: 45.9%

#3005Easy

Count Elements With Maximum Frequency

ArrayCountingHash Table

Acceptance: 79.8%

#3010Easy

Divide an Array Into Subarrays With Minimum Cost I

ArrayEnumerationSorting

Acceptance: 80.5%

#3014Easy

Minimum Number of Pushes to Type Word I

GreedyMathString

Acceptance: 77.1%

#3019Easy

Number of Changing Keys

String

Acceptance: 80.6%

#3024Easy

Type of Triangle

ArrayMathSorting

Acceptance: 44.1%

#3028Easy

Ant on the Boundary

ArrayPrefix SumSimulation

Acceptance: 74.6%

#3032Easy

Count Numbers With Unique Digits II

Dynamic ProgrammingHash TableMath

Acceptance: 87.4%

#3033Easy

Modify the Matrix

ArrayMatrix

Acceptance: 69.1%

#3038Easy

Maximum Number of Operations With the Same Score I

ArraySimulation

Acceptance: 52.8%

#3042Easy

Count Prefix and Suffix Pairs I

ArrayHash FunctionRolling Hash+3

Acceptance: 77.8%

#3046Easy

Split the Array

ArrayCountingHash Table

Acceptance: 61.7%

#3051Easy

Find Candidates for Data Scientist Position

Database

Acceptance: 74.7%

#3053Easy

Classifying Triangles by Lengths

Database

Acceptance: 50.3%

#3059Easy

Find All Unique Email Domains

Database

Acceptance: 69.0%

#3062Easy

Winner of the Linked List Game

Linked List

Acceptance: 77.6%

#3063Easy

Linked List Frequency

CountingHash TableLinked List

Acceptance: 85.8%

#3065Easy

Minimum Operations to Exceed Threshold Value I

Array

Acceptance: 86.7%

#3069Easy

Distribute Elements Into Two Arrays I

ArraySimulation

Acceptance: 83.4%

#3074Easy

Apple Redistribution into Boxes

ArrayGreedySorting

Acceptance: 78.5%

#3079Easy

Find the Sum of Encrypted Integers

ArrayMath

Acceptance: 74.7%

#3083Easy

Existence of a Substring in a String and Its Reverse

Hash TableString

Acceptance: 66.6%

#3090Easy

Maximum Length Substring With Two Occurrences

Hash TableSliding WindowString

Acceptance: 77.4%

#3095Easy

Shortest Subarray With OR at Least K I

ArrayBit ManipulationSliding Window

Acceptance: 44.9%

#3099Easy

Harshad Number

Math

Acceptance: 83.4%

#3105Easy

Longest Strictly Increasing or Strictly Decreasing Subarray

Array

Acceptance: 64.9%

#3110Easy

Score of a String

String

Acceptance: 91.4%

#3114Easy

Latest Time You Can Obtain After Replacing Characters

EnumerationString

Acceptance: 35.4%

#3120Easy

Count the Number of Special Characters I

Hash TableString

Acceptance: 77.2%

#3127Easy

Make a Square with the Same Color

ArrayEnumerationMatrix

Acceptance: 53.0%

#3131Easy

Find the Integer Added to Array I

Array

Acceptance: 82.9%

#3136Easy

Valid Word

String

Acceptance: 50.9%

#3142Easy

Check if Grid Satisfies Conditions

ArrayMatrix

Acceptance: 45.7%

#3146Easy

Permutation Difference between Two Strings

Hash TableString

Acceptance: 87.9%

#3150Easy

Invalid Tweets II

Database

Acceptance: 87.0%

#3151Easy

Special Array I

Array

Acceptance: 81.6%

#3158Easy

Find the XOR of Numbers Which Appear Twice

ArrayBit ManipulationHash Table

Acceptance: 78.9%

#3162Easy

Find the Number of Good Pairs I

ArrayHash Table

Acceptance: 86.4%

#3168Easy

Minimum Number of Chairs in a Waiting Room

SimulationString

Acceptance: 79.3%

#3172Easy

Second Day Verification

Database

Acceptance: 70.7%

#3173Easy

Bitwise OR of Adjacent Elements

ArrayBit Manipulation

Acceptance: 94.8%

#3174Easy

Clear Digits

SimulationStackString

Acceptance: 82.7%

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Master DSA with Step-by-Step Solutions

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