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
3885. Design Event Manager	Medium	50.3%	Array Design+3	Read
3884. First Matching Character From Both Ends	Easy	81.5%	String Two Pointers	Read
3883. Count Non Decreasing Arrays With Given Digit Sums	Hard	40.3%	Array Dynamic Programming+1	Read
3886. Sum of Sortable Integers	Hard	31.8%	Array Enumeration+2	Read
3880. Minimum Absolute Difference Between Two Values	Easy	66.2%	Array Enumeration	Read
3881. Direction Assignments with Exactly K Visible People	Medium	35.7%	Combinatorics Math	Read
3882. Minimum XOR Path in a Grid	Medium	39.5%	Array Bit Manipulation+2	Read
3887. Incremental Even-Weighted Cycle Queries	Hard	49.1%	Graph Union Find	Read
3893. Maximum Team Size with Overlapping Intervals	Medium	42.6%		Read
3889. Mirror Frequency Distance	Medium	60.7%	Counting Hash Table+1	Read
3890. Integers With Multiple Sum of Two Cubes	Medium	54.9%	Counting Enumeration+2	Read
3892. Minimum Operations to Achieve At Least K Peaks	Hard	30.6%	Array Dynamic Programming	Read
3891. Minimum Increase to Maximize Special Indices	Medium	19.8%	Array Dynamic Programming+2	Read
3895. Count Digit Appearances	Medium	86.2%	Array Math	Read
3897. Maximum Value of Concatenated Binary Segments	Hard	26.7%	Array Greedy+1	Read
3896. Minimum Operations to Transform Array into Alternating Prime	Medium	53.2%	Array Binary Search+4	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
3899. Angles of a Triangle	Medium	62.5%	Array Geometry+1	Read
3900. Longest Balanced Substring After One Swap	Medium	14.2%	Hash Table Prefix Sum+1	Read
3901. Good Subsequence Queries	Hard	20.6%	Array Math+2	Read
3902. Zigzag Level Sum of Binary Tree	Medium	69.5%		Read
3907. Count Smaller Elements With Opposite Parity	Medium	72.7%		Read
3904. Smallest Stable Index II	Medium	74.7%	Array	Read
3903. Smallest Stable Index I	Easy	76.5%	Array	Read
3905. Multi Source Flood Fill	Medium	56.3%	Array Breadth-First Search+1	Read
3906. Count Good Integers on a Grid Path	Hard	49.6%	Dynamic Programming	Read
3909. Compare Sums of Bitonic Parts	Medium	52.8%	Array	Read
3912. Valid Elements in an Array	Easy	56.7%	Array	Read
3911. K-th Smallest Remaining Even Integer in Subarray Queries	Hard	28.6%	Array Binary Search	Read
3908. Valid Digit Number	Easy	69.8%	Math	Read
3913. Sort Vowels by Frequency	Medium	61.5%	Counting Sorting+1	Read
3910. Count Connected Subgraphs with Even Node Sum	Hard	59.0%	Array Bit Manipulation+5	Read
3914. Minimum Operations to Make Array Non Decreasing	Medium	54.9%	Array Greedy	Read
3915. Maximum Sum of Alternating Subsequence With Distance at Least K	Hard	30.7%	Array Dynamic Programming+1	Read
3916. Number of ZigZag Arrays III	Hard	62.9%		Read
3927. Minimize Array Sum Using Divisible Replacements	Medium	32.2%	Array Greedy+3	Read
3925. Concatenate Array With Reverse	Easy	91.1%	Array Simulation	Read
3918. Sum of Primes Between Number and Its Reverse	Medium	75.3%	Math Number Theory	Read
3917. Count Indices With Opposite Parity	Easy	80.5%	Array	Read
3920. Maximize Fixed Points After Deletions	Hard	19.9%	Array Binary Search+1	Read
3926. Count Valid Word Occurrences	Medium	48.1%	Array Counting+2	Read
3919. Minimum Cost to Move Between Indices	Medium	49.4%	Array Greedy+1	Read
3921. Score Validator	Easy	72.5%	Array Simulation+1	Read
3923. Minimum Generations to Target Point	Medium	42.9%	Array Hash Table+1	Read
3922. Minimum Flips to Make Binary String Coherent	Medium	19.9%	String	Read
3924. Minimum Threshold Path With Limited Heavy Edges	Hard	39.0%	Binary Search Breadth-First Search+1	Read
3928. Minimum Cost to Buy Apples II	Hard	31.8%	Array Graph+2	Read
3929. Minimum Partition Score II	Hard	44.8%		Read
3930. Power Update After K-th Largest Insertion II	Hard	81.3%		Read

#3885Medium

Design Event Manager

ArrayDesignHash Table+2

Acceptance: 50.3%

#3884Easy

First Matching Character From Both Ends

StringTwo Pointers

Acceptance: 81.5%

#3883Hard

Count Non Decreasing Arrays With Given Digit Sums

ArrayDynamic ProgrammingPrefix Sum

Acceptance: 40.3%

#3886Hard

Sum of Sortable Integers

ArrayEnumerationMath+1

Acceptance: 31.8%

#3880Easy

Minimum Absolute Difference Between Two Values

ArrayEnumeration

Acceptance: 66.2%

#3881Medium

Direction Assignments with Exactly K Visible People

CombinatoricsMath

Acceptance: 35.7%

#3882Medium

Minimum XOR Path in a Grid

ArrayBit ManipulationDynamic Programming+1

Acceptance: 39.5%

#3887Hard

Incremental Even-Weighted Cycle Queries

GraphUnion Find

Acceptance: 49.1%

#3893Medium

Maximum Team Size with Overlapping Intervals

Acceptance: 42.6%

#3889Medium

Mirror Frequency Distance

CountingHash TableString

Acceptance: 60.7%

#3890Medium

Integers With Multiple Sum of Two Cubes

CountingEnumerationHash Table+1

Acceptance: 54.9%

#3892Hard

Minimum Operations to Achieve At Least K Peaks

ArrayDynamic Programming

Acceptance: 30.6%

#3891Medium

Minimum Increase to Maximize Special Indices

ArrayDynamic ProgrammingGreedy+1

Acceptance: 19.8%

#3895Medium

Count Digit Appearances

ArrayMath

Acceptance: 86.2%

#3897Hard

Maximum Value of Concatenated Binary Segments

ArrayGreedySorting

Acceptance: 26.7%

#3896Medium

Minimum Operations to Transform Array into Alternating Prime

ArrayBinary SearchMath+3

Acceptance: 53.2%

#3894Easy

Traffic Signal Color

MathSimulationString

Acceptance: 82.7%

#3898Easy

Find the Degree of Each Vertex

ArrayGraphMatrix

Acceptance: 91.8%

#3899Medium

Angles of a Triangle

ArrayGeometryMath

Acceptance: 62.5%

#3900Medium

Longest Balanced Substring After One Swap

Hash TablePrefix SumString

Acceptance: 14.2%

#3901Hard

Good Subsequence Queries

ArrayMathNumber Theory+1

Acceptance: 20.6%

#3902Medium

Zigzag Level Sum of Binary Tree

Acceptance: 69.5%

#3907Medium

Count Smaller Elements With Opposite Parity

Acceptance: 72.7%

#3904Medium

Smallest Stable Index II

Array

Acceptance: 74.7%

#3903Easy

Smallest Stable Index I

Array

Acceptance: 76.5%

#3905Medium

Multi Source Flood Fill

ArrayBreadth-First SearchMatrix

Acceptance: 56.3%

#3906Hard

Count Good Integers on a Grid Path

Dynamic Programming

Acceptance: 49.6%

#3909Medium

Compare Sums of Bitonic Parts

Array

Acceptance: 52.8%

#3912Easy

Valid Elements in an Array

Array

Acceptance: 56.7%

#3911Hard

K-th Smallest Remaining Even Integer in Subarray Queries

ArrayBinary Search

Acceptance: 28.6%

#3908Easy

Valid Digit Number

Math

Acceptance: 69.8%

#3913Medium

Sort Vowels by Frequency

CountingSortingString

Acceptance: 61.5%

#3910Hard

Count Connected Subgraphs with Even Node Sum

ArrayBit ManipulationBreadth-First Search+4

Acceptance: 59.0%

#3914Medium

Minimum Operations to Make Array Non Decreasing

ArrayGreedy

Acceptance: 54.9%

#3915Hard

Maximum Sum of Alternating Subsequence With Distance at Least K

ArrayDynamic ProgrammingSegment Tree

Acceptance: 30.7%

#3916Hard

Number of ZigZag Arrays III

Acceptance: 62.9%

#3927Medium

Minimize Array Sum Using Divisible Replacements

ArrayGreedyHash Table+2

Acceptance: 32.2%

#3925Easy

Concatenate Array With Reverse

ArraySimulation

Acceptance: 91.1%

#3918Medium

Sum of Primes Between Number and Its Reverse

MathNumber Theory

Acceptance: 75.3%

#3917Easy

Count Indices With Opposite Parity

Array

Acceptance: 80.5%

#3920Hard

Maximize Fixed Points After Deletions

ArrayBinary SearchSorting

Acceptance: 19.9%

#3926Medium

Count Valid Word Occurrences

ArrayCountingHash Table+1

Acceptance: 48.1%

#3919Medium

Minimum Cost to Move Between Indices

ArrayGreedyPrefix Sum

Acceptance: 49.4%

#3921Easy

Score Validator

ArraySimulationString

Acceptance: 72.5%

#3923Medium

Minimum Generations to Target Point

ArrayHash TableSimulation

Acceptance: 42.9%

#3922Medium

Minimum Flips to Make Binary String Coherent

String

Acceptance: 19.9%

#3924Hard

Minimum Threshold Path With Limited Heavy Edges

Binary SearchBreadth-First SearchGraph

Acceptance: 39.0%

#3928Hard

Minimum Cost to Buy Apples II

ArrayGraphHeap (Priority Queue)+1

Acceptance: 31.8%

#3929Hard

Minimum Partition Score II

Acceptance: 44.8%

#3930Hard

Power Update After K-th Largest Insertion II

Acceptance: 81.3%

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