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
3838. Weighted Word Mapping	Easy	90.7%	Array Simulation+1	Read
3833. Count Dominant Indices	Easy	65.8%	Array Enumeration	Read
3834. Merge Adjacent Equal Elements	Medium	42.6%	Array Simulation+1	Read
3842. Toggle Light Bulbs	Easy	71.2%	Array Hash Table+2	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
3841. Palindromic Path Queries in a Tree	Hard	34.8%	Array Divide and Conquer+3	Read
3817. Good Indices in a Digit String	Medium	85.9%	Math String	Read
3845. Maximum Subarray XOR with Bounded Range	Hard	32.3%	Array Bit Manipulation+5	Read
3836. Maximum Score Using Exactly K Pairs	Hard	41.4%	Array Dynamic Programming	Read
3822. Design Order Management System	Medium	79.0%	Design Hash Table	Read
3823. Reverse Letters Then Special Characters in a String	Easy	81.5%	Simulation String+1	Read
3818. Minimum Prefix Removal to Make Array Strictly Increasing	Medium	73.7%	Array	Read
3830. Longest Alternating Subarray After Removing At Most One Element	Hard	30.9%	Array Dynamic Programming+1	Read
3807. Minimum Cost to Repair Edges to Traverse a Graph	Medium	55.0%	Binary Search Breadth-First Search+1	Read
3827. Count Monobit Integers	Easy	66.0%	Bit Manipulation Enumeration	Read
3864. Minimum Cost to Partition a Binary String	Hard	50.5%	Divide and Conquer Prefix Sum+1	Read
3810. Minimum Operations to Reach Target Array	Medium	62.7%	Array Greedy+1	Read
3821. Find Nth Smallest Integer With K One Bits	Hard	34.7%	Bit Manipulation Combinatorics+1	Read
3809. Best Reachable Tower	Medium	55.7%	Array	Read
3803. Count Residue Prefixes	Easy	66.0%	Hash Table String	Read
3805. Count Caesar Cipher Pairs	Medium	50.7%	Array Counting+3	Read
3812. Minimum Edge Toggles on a Tree	Hard	65.6%	Depth-First Search Graph+3	Read
3820. Pythagorean Distance Nodes in a Tree	Medium	56.6%	Breadth-First Search Tree	Read
3798. Largest Even Number	Easy	68.5%	String	Read
3813. Vowel-Consonant Score	Easy	53.3%	Simulation String	Read
3794. Reverse String Prefix	Easy	88.5%	String Two Pointers	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
3783. Mirror Distance of an Integer	Easy	91.5%	Math	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
3782. Last Remaining Integer After Alternating Deletion Operations	Hard	49.2%	Math Recursion	Read
3779. Minimum Number of Operations to Have Distinct Elements	Medium	42.1%	Array Hash Table	Read
3858. Minimum Bitwise OR From Grid	Medium	27.5%	Array Bit Manipulation+2	Read
3780. Maximum Sum of Three Numbers Divisible by Three	Medium	46.7%	Array Greedy+2	Read
3869. Count Fancy Numbers in a Range	Hard	26.6%	Dynamic Programming Math	Read
3774. Absolute Difference Between Maximum and Minimum K Elements	Easy	74.8%	Array Sorting	Read
3775. Reverse Words With Same Vowel Count	Medium	66.6%	Simulation String+1	Read
3800. Minimum Cost to Make Two Binary Strings Equal	Medium	38.6%	Greedy String	Read
3773. Maximum Number of Equal Length Runs	Medium	82.8%	Counting Hash Table+1	Read
3806. Maximum Bitwise AND After Increment Operations	Hard	31.2%	Array Bit Manipulation+2	Read
3797. Count Routes to Climb a Rectangular Grid	Hard	25.5%	Array Dynamic Programming+2	Read
3795. Minimum Subarray Length With Distinct Sum At Least K	Medium	31.7%	Array Hash Table+1	Read
3772. Maximum Subgraph Score in a Tree	Hard	65.4%	Array Depth-First Search+2	Read
3769. Sort Integers by Binary Reflection	Easy	60.2%	Array Sorting	Read

#3838Easy

Weighted Word Mapping

ArraySimulationString

Acceptance: 90.7%

#3833Easy

Count Dominant Indices

ArrayEnumeration

Acceptance: 65.8%

#3834Medium

Merge Adjacent Equal Elements

ArraySimulationStack

Acceptance: 42.6%

#3842Easy

Toggle Light Bulbs

ArrayHash TableSimulation+1

Acceptance: 71.2%

#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%

#3841Hard

Palindromic Path Queries in a Tree

ArrayDivide and ConquerSegment Tree+2

Acceptance: 34.8%

#3817Medium

Good Indices in a Digit String

MathString

Acceptance: 85.9%

#3845Hard

Maximum Subarray XOR with Bounded Range

ArrayBit ManipulationMonotonic Queue+4

Acceptance: 32.3%

#3836Hard

Maximum Score Using Exactly K Pairs

ArrayDynamic Programming

Acceptance: 41.4%

#3822Medium

Design Order Management System

DesignHash Table

Acceptance: 79.0%

#3823Easy

Reverse Letters Then Special Characters in a String

SimulationStringTwo Pointers

Acceptance: 81.5%

#3818Medium

Minimum Prefix Removal to Make Array Strictly Increasing

Array

Acceptance: 73.7%

#3830Hard

Longest Alternating Subarray After Removing At Most One Element

ArrayDynamic ProgrammingEnumeration

Acceptance: 30.9%

#3807Medium

Minimum Cost to Repair Edges to Traverse a Graph

Binary SearchBreadth-First SearchGraph

Acceptance: 55.0%

#3827Easy

Count Monobit Integers

Bit ManipulationEnumeration

Acceptance: 66.0%

#3864Hard

Minimum Cost to Partition a Binary String

Divide and ConquerPrefix SumString

Acceptance: 50.5%

#3810Medium

Minimum Operations to Reach Target Array

ArrayGreedyHash Table

Acceptance: 62.7%

#3821Hard

Find Nth Smallest Integer With K One Bits

Bit ManipulationCombinatoricsMath

Acceptance: 34.7%

#3809Medium

Best Reachable Tower

Array

Acceptance: 55.7%

#3803Easy

Count Residue Prefixes

Hash TableString

Acceptance: 66.0%

#3805Medium

Count Caesar Cipher Pairs

ArrayCountingHash Table+2

Acceptance: 50.7%

#3812Hard

Minimum Edge Toggles on a Tree

Depth-First SearchGraphSorting+2

Acceptance: 65.6%

#3820Medium

Pythagorean Distance Nodes in a Tree

Breadth-First SearchTree

Acceptance: 56.6%

#3798Easy

Largest Even Number

String

Acceptance: 68.5%

#3813Easy

Vowel-Consonant Score

SimulationString

Acceptance: 53.3%

#3794Easy

Reverse String Prefix

StringTwo Pointers

Acceptance: 88.5%

#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%

#3783Easy

Mirror Distance of an Integer

Math

Acceptance: 91.5%

#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%

#3782Hard

Last Remaining Integer After Alternating Deletion Operations

MathRecursion

Acceptance: 49.2%

#3779Medium

Minimum Number of Operations to Have Distinct Elements

ArrayHash Table

Acceptance: 42.1%

#3858Medium

Minimum Bitwise OR From Grid

ArrayBit ManipulationGreedy+1

Acceptance: 27.5%

#3780Medium

Maximum Sum of Three Numbers Divisible by Three

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 46.7%

#3869Hard

Count Fancy Numbers in a Range

Dynamic ProgrammingMath

Acceptance: 26.6%

#3774Easy

Absolute Difference Between Maximum and Minimum K Elements

ArraySorting

Acceptance: 74.8%

#3775Medium

Reverse Words With Same Vowel Count

SimulationStringTwo Pointers

Acceptance: 66.6%

#3800Medium

Minimum Cost to Make Two Binary Strings Equal

GreedyString

Acceptance: 38.6%

#3773Medium

Maximum Number of Equal Length Runs

CountingHash TableString

Acceptance: 82.8%

#3806Hard

Maximum Bitwise AND After Increment Operations

ArrayBit ManipulationGreedy+1

Acceptance: 31.2%

#3797Hard

Count Routes to Climb a Rectangular Grid

ArrayDynamic ProgrammingMatrix+1

Acceptance: 25.5%

#3795Medium

Minimum Subarray Length With Distinct Sum At Least K

ArrayHash TableSliding Window

Acceptance: 31.7%

#3772Hard

Maximum Subgraph Score in a Tree

ArrayDepth-First SearchDynamic Programming+1

Acceptance: 65.4%

#3769Easy

Sort Integers by Binary Reflection

ArraySorting

Acceptance: 60.2%

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