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
3516. Find Closest Person	Easy	88.9%	Math	Read
3492. Maximum Containers on a Ship	Easy	75.2%	Math	Read
3498. Reverse Degree of a String	Easy	91.9%	Simulation String	Read
3483. Unique 3-Digit Even Numbers	Easy	79.8%	Array Enumeration+2	Read
3477. Fruits Into Baskets II	Easy	70.2%	Array Binary Search+3	Read
3487. Maximum Unique Subarray Sum After Deletion	Easy	40.5%	Array Greedy+1	Read
3450. Maximum Students on a Single Bench	Easy	87.8%	Array Hash Table	Read
3467. Transform Array by Parity	Easy	89.7%	Array Counting+1	Read
3507. Minimum Pair Removal to Sort Array I	Easy	65.3%	Array Doubly-Linked List+5	Read
3461. Check If Digits Are Equal in String After Operations I	Easy	82.5%	Combinatorics Math+3	Read
3442. Maximum Difference Between Even and Odd Frequency I	Easy	60.7%	Counting Hash Table+1	Read
3423. Maximum Difference Between Adjacent Elements in a Circular Array	Easy	75.7%	Array	Read
3438. Find Valid Pair of Adjacent Digits in String	Easy	60.7%	Counting Hash Table+1	Read
3427. Sum of Variable Length Subarrays	Easy	85.6%	Array Prefix Sum	Read
3452. Sum of Good Numbers	Easy	69.6%	Array	Read
3456. Find Special Substring of Length K	Easy	35.1%	String	Read
3417. Zigzag Grid Traversal With Skip	Easy	64.9%	Array Matrix+1	Read
3471. Find the Largest Almost Missing Integer	Easy	49.4%	Array Hash Table	Read
3432. Count Partitions with Even Sum Difference	Easy	85.2%	Array Math+1	Read
3411. Maximum Subarray With Equal Products	Easy	47.2%	Array Enumeration+3	Read
3402. Minimum Operations to Make Columns Strictly Increasing	Easy	71.9%	Array Greedy+1	Read
3392. Count Subarrays of Length Three With a Condition	Easy	61.5%	Array	Read
3407. Substring Matching Pattern	Easy	29.1%	String String Matching	Read
3396. Minimum Number of Operations to Make Elements in Array Distinct	Easy	71.3%	Array Hash Table	Read
3379. Transformed Array	Easy	70.5%	Array Simulation	Read
3386. Button with Longest Push Time	Easy	41.0%	Array	Read
3375. Minimum Operations to Make Array Values Equal to K	Easy	73.3%	Array Hash Table	Read
3884. First Matching Character From Both Ends	Easy	81.5%	String Two Pointers	Read
3880. Minimum Absolute Difference Between Two Values	Easy	66.2%	Array Enumeration	Read
3894. Traffic Signal Color	Easy	82.7%	Math Simulation+1	Read
3898. Find the Degree of Each Vertex	Easy	91.8%	Array Graph+1	Read
3903. Smallest Stable Index I	Easy	76.5%	Array	Read
3912. Valid Elements in an Array	Easy	56.7%	Array	Read
3908. Valid Digit Number	Easy	69.8%	Math	Read
3925. Concatenate Array With Reverse	Easy	91.1%	Array Simulation	Read
3917. Count Indices With Opposite Parity	Easy	80.5%	Array	Read
3921. Score Validator	Easy	72.5%	Array Simulation+1	Read
3931. Check Adjacent Digit Differences	Easy	77.1%	String	Read
3936. Minimum Swaps to Move Zeros to End	Easy	59.7%	Array Two Pointers	Read
3940. Limit Occurrences in Sorted Array	Easy	72.6%	Array Two Pointers	Read
3945. Digit Frequency Score	Easy	90.7%	Hash Table Math	Read
3954. Sum of Compatible Numbers in Range I	Easy	58.4%	Bit Manipulation Dynamic Programming+1	Read
3950. Exactly One Consecutive Set Bits Pair	Easy	50.4%	Bit Manipulation	Read
3959. Check Good Integer	Easy	82.6%	Math Simulation	Read
3963. Create Grid With Exactly One Path	Easy	75.9%		Read
3996. Even Number of Knight Moves	Easy	74.5%	Array Math	Read
3986. Number of Elapsed Seconds Between Two Times	Easy	82.5%	Math String	Read
3982. Sum of Integers with Maximum Digit Range	Easy	72.9%	Array Math	Read
3992. Rearrange String to Avoid Character Pair	Easy	77.8%	Sorting String+1	Read
3978. Unique Middle Element	Easy	72.3%	Array Counting	Read

#3516Easy

Find Closest Person

Math

Acceptance: 88.9%

#3492Easy

Maximum Containers on a Ship

Math

Acceptance: 75.2%

#3498Easy

Reverse Degree of a String

SimulationString

Acceptance: 91.9%

#3483Easy

Unique 3-Digit Even Numbers

ArrayEnumerationHash Table+1

Acceptance: 79.8%

#3477Easy

Fruits Into Baskets II

ArrayBinary SearchOrdered Set+2

Acceptance: 70.2%

#3487Easy

Maximum Unique Subarray Sum After Deletion

ArrayGreedyHash Table

Acceptance: 40.5%

#3450Easy

Maximum Students on a Single Bench

ArrayHash Table

Acceptance: 87.8%

#3467Easy

Transform Array by Parity

ArrayCountingSorting

Acceptance: 89.7%

#3507Easy

Minimum Pair Removal to Sort Array I

ArrayDoubly-Linked ListHash Table+4

Acceptance: 65.3%

#3461Easy

Check If Digits Are Equal in String After Operations I

CombinatoricsMathNumber Theory+2

Acceptance: 82.5%

#3442Easy

Maximum Difference Between Even and Odd Frequency I

CountingHash TableString

Acceptance: 60.7%

#3423Easy

Maximum Difference Between Adjacent Elements in a Circular Array

Array

Acceptance: 75.7%

#3438Easy

Find Valid Pair of Adjacent Digits in String

CountingHash TableString

Acceptance: 60.7%

#3427Easy

Sum of Variable Length Subarrays

ArrayPrefix Sum

Acceptance: 85.6%

#3452Easy

Sum of Good Numbers

Array

Acceptance: 69.6%

#3456Easy

Find Special Substring of Length K

String

Acceptance: 35.1%

#3417Easy

Zigzag Grid Traversal With Skip

ArrayMatrixSimulation

Acceptance: 64.9%

#3471Easy

Find the Largest Almost Missing Integer

ArrayHash Table

Acceptance: 49.4%

#3432Easy

Count Partitions with Even Sum Difference

ArrayMathPrefix Sum

Acceptance: 85.2%

#3411Easy

Maximum Subarray With Equal Products

ArrayEnumerationMath+2

Acceptance: 47.2%

#3402Easy

Minimum Operations to Make Columns Strictly Increasing

ArrayGreedyMatrix

Acceptance: 71.9%

#3392Easy

Count Subarrays of Length Three With a Condition

Array

Acceptance: 61.5%

#3407Easy

Substring Matching Pattern

StringString Matching

Acceptance: 29.1%

#3396Easy

Minimum Number of Operations to Make Elements in Array Distinct

ArrayHash Table

Acceptance: 71.3%

#3379Easy

Transformed Array

ArraySimulation

Acceptance: 70.5%

#3386Easy

Button with Longest Push Time

Array

Acceptance: 41.0%

#3375Easy

Minimum Operations to Make Array Values Equal to K

ArrayHash Table

Acceptance: 73.3%

#3884Easy

First Matching Character From Both Ends

StringTwo Pointers

Acceptance: 81.5%

#3880Easy

Minimum Absolute Difference Between Two Values

ArrayEnumeration

Acceptance: 66.2%

#3894Easy

Traffic Signal Color

MathSimulationString

Acceptance: 82.7%

#3898Easy

Find the Degree of Each Vertex

ArrayGraphMatrix

Acceptance: 91.8%

#3903Easy

Smallest Stable Index I

Array

Acceptance: 76.5%

#3912Easy

Valid Elements in an Array

Array

Acceptance: 56.7%

#3908Easy

Valid Digit Number

Math

Acceptance: 69.8%

#3925Easy

Concatenate Array With Reverse

ArraySimulation

Acceptance: 91.1%

#3917Easy

Count Indices With Opposite Parity

Array

Acceptance: 80.5%

#3921Easy

Score Validator

ArraySimulationString

Acceptance: 72.5%

#3931Easy

Check Adjacent Digit Differences

String

Acceptance: 77.1%

#3936Easy

Minimum Swaps to Move Zeros to End

ArrayTwo Pointers

Acceptance: 59.7%

#3940Easy

Limit Occurrences in Sorted Array

ArrayTwo Pointers

Acceptance: 72.6%

#3945Easy

Digit Frequency Score

Hash TableMath

Acceptance: 90.7%

#3954Easy

Sum of Compatible Numbers in Range I

Bit ManipulationDynamic ProgrammingEnumeration

Acceptance: 58.4%

#3950Easy

Exactly One Consecutive Set Bits Pair

Bit Manipulation

Acceptance: 50.4%

#3959Easy

Check Good Integer

MathSimulation

Acceptance: 82.6%

#3963Easy

Create Grid With Exactly One Path

Acceptance: 75.9%

#3996Easy

Even Number of Knight Moves

ArrayMath

Acceptance: 74.5%

#3986Easy

Number of Elapsed Seconds Between Two Times

MathString

Acceptance: 82.5%

#3982Easy

Sum of Integers with Maximum Digit Range

ArrayMath

Acceptance: 72.9%

#3992Easy

Rearrange String to Avoid Character Pair

SortingStringTwo Pointers

Acceptance: 77.8%

#3978Easy

Unique Middle Element

ArrayCounting

Acceptance: 72.3%

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Master DSA with Step-by-Step Solutions

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Try the problem first: Spend at least 20 minutes before reading the solution
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