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
3341. Find Minimum Time to Reach Last Room I	Medium	55.5%	Array Graph+3	Read
3342. Find Minimum Time to Reach Last Room II	Medium	67.3%	Array Graph+3	Read
3344. Maximum Sized Array	Medium	51.4%	Binary Search Bit Manipulation	Read
3346. Maximum Frequency of an Element After Performing Operations I	Medium	40.1%	Array Binary Search+3	Read
3350. Adjacent Increasing Subarrays Detection II	Medium	58.9%	Array Binary Search	Read
3355. Zero Array Transformation I	Medium	54.5%	Array Prefix Sum	Read
3356. Zero Array Transformation II	Medium	43.6%	Array Binary Search+1	Read
3361. Shift Distance Between Two Strings	Medium	52.8%	Array Prefix Sum+1	Read
3362. Zero Array Transformation III	Medium	54.9%	Array Greedy+3	Read
3365. Rearrange K Substrings to Form Target String	Medium	56.7%	Hash Table Sorting+1	Read
3366. Minimum Array Sum	Medium	31.7%	Array Dynamic Programming	Read
3371. Identify the Largest Outlier in an Array	Medium	36.2%	Array Counting+2	Read
3372. Maximize the Number of Target Nodes After Connecting Trees I	Medium	69.5%	Breadth-First Search Depth-First Search+1	Read
3874. Valid Subarrays With Exactly One Peak	Medium	66.9%		Read
3865. Reverse K Subarrays	Medium	88.6%	Array Two Pointers	Read
3876. Construct Uniform Parity Array II	Medium	66.3%	Array Math	Read
3868. Minimum Cost to Equalize Arrays Using Swaps	Medium	48.7%	Array Counting+2	Read
3851. Maximum Requests Without Violating the Limit	Medium	63.5%	Array Greedy+3	Read
3871. Count Commas in Range II	Medium	49.3%	Math	Read
3867. Sum of GCD of Formed Pairs	Medium	75.1%	Array Math+3	Read
3860. Unique Email Groups	Medium	84.8%	Array Hash Table+1	Read
3862. Find the Smallest Balanced Index	Medium	19.2%	Array Prefix Sum	Read
3872. Longest Arithmetic Sequence After Changing At Most One Element	Medium	21.4%	Array Enumeration	Read
3837. Delayed Count of Equal Elements	Medium	78.3%	Array Counting+1	Read
3848. Check Digitorial Permutation	Medium	46.5%	Counting Math	Read
3847. Find the Score Difference in a Game	Medium	72.7%	Array Simulation	Read
3844. Longest Almost-Palindromic Substring	Medium	22.8%	Dynamic Programming String+1	Read
3863. Minimum Operations to Sort a String	Medium	19.1%	String	Read
3854. Minimum Operations to Make Array Parity Alternating	Medium	17.1%	Array Greedy	Read
3843. First Element with Unique Frequency	Medium	69.9%	Array Counting+1	Read
3834. Merge Adjacent Equal Elements	Medium	42.6%	Array Simulation+1	Read
3835. Count Subarrays With Cost Less Than or Equal to K	Medium	46.1%	Array Monotonic Queue+1	Read
3831. Median of a Binary Search Tree Level	Medium	86.4%	Binary Search Tree Binary Tree+3	Read
3817. Good Indices in a Digit String	Medium	85.9%	Math String	Read
3822. Design Order Management System	Medium	79.0%	Design Hash Table	Read
3818. Minimum Prefix Removal to Make Array Strictly Increasing	Medium	73.7%	Array	Read
3807. Minimum Cost to Repair Edges to Traverse a Graph	Medium	55.0%	Binary Search Breadth-First Search+1	Read
3810. Minimum Operations to Reach Target Array	Medium	62.7%	Array Greedy+1	Read
3809. Best Reachable Tower	Medium	55.7%	Array	Read
3805. Count Caesar Cipher Pairs	Medium	50.7%	Array Counting+3	Read
3820. Pythagorean Distance Nodes in a Tree	Medium	56.6%	Breadth-First Search Tree	Read
3824. Minimum K to Reduce Array Within Limit	Medium	41.1%	Array Binary Search	Read
3790. Smallest All-Ones Multiple	Medium	46.8%	Hash Table Math	Read
3788. Maximum Score of a Split	Medium	51.6%	Array Prefix Sum	Read
3792. Sum of Increasing Product Blocks	Medium	67.7%	Math Simulation	Read
3819. Rotate Non Negative Elements	Medium	47.9%	Array Simulation	Read
3846. Total Distance to Type a String Using One Finger	Medium	89.9%	Hash Table String	Read
3763. Maximum Total Sum with Threshold Constraints	Medium	82.4%	Array Greedy+2	Read
3787. Find Diameter Endpoints of a Tree	Medium	65.9%	Breadth-First Search Graph+1	Read
3779. Minimum Number of Operations to Have Distinct Elements	Medium	42.1%	Array Hash Table	Read

#3341Medium

Find Minimum Time to Reach Last Room I

ArrayGraphHeap (Priority Queue)+2

Acceptance: 55.5%

#3342Medium

Find Minimum Time to Reach Last Room II

ArrayGraphHeap (Priority Queue)+2

Acceptance: 67.3%

#3344Medium

Maximum Sized Array

Binary SearchBit Manipulation

Acceptance: 51.4%

#3346Medium

Maximum Frequency of an Element After Performing Operations I

ArrayBinary SearchPrefix Sum+2

Acceptance: 40.1%

#3350Medium

Adjacent Increasing Subarrays Detection II

ArrayBinary Search

Acceptance: 58.9%

#3355Medium

Zero Array Transformation I

ArrayPrefix Sum

Acceptance: 54.5%

#3356Medium

Zero Array Transformation II

ArrayBinary SearchPrefix Sum

Acceptance: 43.6%

#3361Medium

Shift Distance Between Two Strings

ArrayPrefix SumString

Acceptance: 52.8%

#3362Medium

Zero Array Transformation III

ArrayGreedyHeap (Priority Queue)+2

Acceptance: 54.9%

#3365Medium

Rearrange K Substrings to Form Target String

Hash TableSortingString

Acceptance: 56.7%

#3366Medium

Minimum Array Sum

ArrayDynamic Programming

Acceptance: 31.7%

#3371Medium

Identify the Largest Outlier in an Array

ArrayCountingEnumeration+1

Acceptance: 36.2%

#3372Medium

Maximize the Number of Target Nodes After Connecting Trees I

Breadth-First SearchDepth-First SearchTree

Acceptance: 69.5%

#3874Medium

Valid Subarrays With Exactly One Peak

Acceptance: 66.9%

#3865Medium

Reverse K Subarrays

ArrayTwo Pointers

Acceptance: 88.6%

#3876Medium

Construct Uniform Parity Array II

ArrayMath

Acceptance: 66.3%

#3868Medium

Minimum Cost to Equalize Arrays Using Swaps

ArrayCountingGreedy+1

Acceptance: 48.7%

#3851Medium

Maximum Requests Without Violating the Limit

ArrayGreedyHash Table+2

Acceptance: 63.5%

#3871Medium

Count Commas in Range II

Math

Acceptance: 49.3%

#3867Medium

Sum of GCD of Formed Pairs

ArrayMathNumber Theory+2

Acceptance: 75.1%

#3860Medium

Unique Email Groups

ArrayHash TableString

Acceptance: 84.8%

#3862Medium

Find the Smallest Balanced Index

ArrayPrefix Sum

Acceptance: 19.2%

#3872Medium

Longest Arithmetic Sequence After Changing At Most One Element

ArrayEnumeration

Acceptance: 21.4%

#3837Medium

Delayed Count of Equal Elements

ArrayCountingHash Table

Acceptance: 78.3%

#3848Medium

Check Digitorial Permutation

CountingMath

Acceptance: 46.5%

#3847Medium

Find the Score Difference in a Game

ArraySimulation

Acceptance: 72.7%

#3844Medium

Longest Almost-Palindromic Substring

Dynamic ProgrammingStringTwo Pointers

Acceptance: 22.8%

#3863Medium

Minimum Operations to Sort a String

String

Acceptance: 19.1%

#3854Medium

Minimum Operations to Make Array Parity Alternating

ArrayGreedy

Acceptance: 17.1%

#3843Medium

First Element with Unique Frequency

ArrayCountingHash Table

Acceptance: 69.9%

#3834Medium

Merge Adjacent Equal Elements

ArraySimulationStack

Acceptance: 42.6%

#3835Medium

Count Subarrays With Cost Less Than or Equal to K

ArrayMonotonic QueueQueue

Acceptance: 46.1%

#3831Medium

Median of a Binary Search Tree Level

Binary Search TreeBinary TreeBreadth-First Search+2

Acceptance: 86.4%

#3817Medium

Good Indices in a Digit String

MathString

Acceptance: 85.9%

#3822Medium

Design Order Management System

DesignHash Table

Acceptance: 79.0%

#3818Medium

Minimum Prefix Removal to Make Array Strictly Increasing

Array

Acceptance: 73.7%

#3807Medium

Minimum Cost to Repair Edges to Traverse a Graph

Binary SearchBreadth-First SearchGraph

Acceptance: 55.0%

#3810Medium

Minimum Operations to Reach Target Array

ArrayGreedyHash Table

Acceptance: 62.7%

#3809Medium

Best Reachable Tower

Array

Acceptance: 55.7%

#3805Medium

Count Caesar Cipher Pairs

ArrayCountingHash Table+2

Acceptance: 50.7%

#3820Medium

Pythagorean Distance Nodes in a Tree

Breadth-First SearchTree

Acceptance: 56.6%

#3824Medium

Minimum K to Reduce Array Within Limit

ArrayBinary Search

Acceptance: 41.1%

#3790Medium

Smallest All-Ones Multiple

Hash TableMath

Acceptance: 46.8%

#3788Medium

Maximum Score of a Split

ArrayPrefix Sum

Acceptance: 51.6%

#3792Medium

Sum of Increasing Product Blocks

MathSimulation

Acceptance: 67.7%

#3819Medium

Rotate Non Negative Elements

ArraySimulation

Acceptance: 47.9%

#3846Medium

Total Distance to Type a String Using One Finger

Hash TableString

Acceptance: 89.9%

#3763Medium

Maximum Total Sum with Threshold Constraints

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 82.4%

#3787Medium

Find Diameter Endpoints of a Tree

Breadth-First SearchGraphTree

Acceptance: 65.9%

#3779Medium

Minimum Number of Operations to Have Distinct Elements

ArrayHash Table

Acceptance: 42.1%

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