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
3404. Count Special Subsequences	Medium	29.9%	Array Enumeration+2	Read
3422. Minimum Operations to Make Subarray Elements Equal	Medium	46.8%	Array Hash Table+3	Read
3388. Count Beautiful Splits in an Array	Medium	19.3%	Array Dynamic Programming	Read
3403. Find the Lexicographically Largest String From the Box I	Medium	41.0%	Enumeration String+1	Read
3380. Maximum Area Rectangle With Point Constraints I	Medium	51.1%	Array Binary Indexed Tree+5	Read
3408. Design Task Manager	Medium	49.1%	Design Hash Table+2	Read
3418. Maximum Amount of Money Robot Can Earn	Medium	47.9%	Array Dynamic Programming+1	Read
3393. Count Paths With the Given XOR Value	Medium	40.6%	Array Bit Manipulation+2	Read
3394. Check if Grid can be Cut into Sections	Medium	68.3%	Array Sorting	Read
3377. Digit Operations to Make Two Integers Equal	Medium	31.3%	Graph Heap (Priority Queue)+3	Read
3381. Maximum Subarray Sum With Length Divisible by K	Medium	49.6%	Array Hash Table+1	Read
3376. Minimum Time to Break Locks I	Medium	32.8%	Array Backtracking+4	Read
3412. Find Mirror Score of a String	Medium	36.1%	Hash Table Simulation+2	Read
3397. Maximum Number of Distinct Elements After Operations	Medium	52.2%	Array Greedy+1	Read
3387. Maximize Amount After Two Days of Conversions	Medium	60.6%	Array Breadth-First Search+3	Read
3879. Maximum Distinct Path Sum in a Binary Tree	Medium	51.2%		Read
3885. Design Event Manager	Medium	50.3%	Array Design+3	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
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
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
3896. Minimum Operations to Transform Array into Alternating Prime	Medium	53.2%	Array Binary Search+4	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
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
3905. Multi Source Flood Fill	Medium	56.3%	Array Breadth-First Search+1	Read
3909. Compare Sums of Bitonic Parts	Medium	52.8%	Array	Read
3913. Sort Vowels by Frequency	Medium	61.5%	Counting Sorting+1	Read
3914. Minimum Operations to Make Array Non Decreasing	Medium	54.9%	Array Greedy	Read
3927. Minimize Array Sum Using Divisible Replacements	Medium	32.2%	Array Greedy+3	Read
3918. Sum of Primes Between Number and Its Reverse	Medium	75.3%	Math Number Theory	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
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
3932. Count K-th Roots in a Range	Medium	24.6%	Binary Search Math	Read
3935. Power Update After K-th Largest Insertion I	Medium	68.1%		Read
3933. Largest Local Values in a Matrix II	Medium	18.5%	Array Matrix+1	Read
3941. Password Strength	Medium	74.5%	Hash Table String	Read
3937. Minimum Operations to Make Array Modulo Alternating I	Medium	46.5%	Array Enumeration	Read
3942. Minimum Operations to Sort a Permutation	Medium	27.8%	Array	Read
3938. Maximum Path Intersection Sum in a Grid	Medium	25.6%	Array Dynamic Programming+2	Read
3947. Maximum Number of Items From Sale II	Medium	30.2%	Array Greedy+2	Read
3946. Maximum Number of Items From Sale I	Medium	37.3%	Array Dynamic Programming+1	Read
3951. Minimum Energy to Maintain Brightness	Medium	53.4%	Array Sorting	Read

#3404Medium

Count Special Subsequences

ArrayEnumerationHash Table+1

Acceptance: 29.9%

#3422Medium

Minimum Operations to Make Subarray Elements Equal

ArrayHash TableHeap (Priority Queue)+2

Acceptance: 46.8%

#3388Medium

Count Beautiful Splits in an Array

ArrayDynamic Programming

Acceptance: 19.3%

#3403Medium

Find the Lexicographically Largest String From the Box I

EnumerationStringTwo Pointers

Acceptance: 41.0%

#3380Medium

Maximum Area Rectangle With Point Constraints I

ArrayBinary Indexed TreeEnumeration+4

Acceptance: 51.1%

#3408Medium

Design Task Manager

DesignHash TableHeap (Priority Queue)+1

Acceptance: 49.1%

#3418Medium

Maximum Amount of Money Robot Can Earn

ArrayDynamic ProgrammingMatrix

Acceptance: 47.9%

#3393Medium

Count Paths With the Given XOR Value

ArrayBit ManipulationDynamic Programming+1

Acceptance: 40.6%

#3394Medium

Check if Grid can be Cut into Sections

ArraySorting

Acceptance: 68.3%

#3377Medium

Digit Operations to Make Two Integers Equal

GraphHeap (Priority Queue)Math+2

Acceptance: 31.3%

#3381Medium

Maximum Subarray Sum With Length Divisible by K

ArrayHash TablePrefix Sum

Acceptance: 49.6%

#3376Medium

Minimum Time to Break Locks I

ArrayBacktrackingBit Manipulation+3

Acceptance: 32.8%

#3412Medium

Find Mirror Score of a String

Hash TableSimulationStack+1

Acceptance: 36.1%

#3397Medium

Maximum Number of Distinct Elements After Operations

ArrayGreedySorting

Acceptance: 52.2%

#3387Medium

Maximize Amount After Two Days of Conversions

ArrayBreadth-First SearchDepth-First Search+2

Acceptance: 60.6%

#3879Medium

Maximum Distinct Path Sum in a Binary Tree

Acceptance: 51.2%

#3885Medium

Design Event Manager

ArrayDesignHash Table+2

Acceptance: 50.3%

#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%

#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%

#3891Medium

Minimum Increase to Maximize Special Indices

ArrayDynamic ProgrammingGreedy+1

Acceptance: 19.8%

#3895Medium

Count Digit Appearances

ArrayMath

Acceptance: 86.2%

#3896Medium

Minimum Operations to Transform Array into Alternating Prime

ArrayBinary SearchMath+3

Acceptance: 53.2%

#3899Medium

Angles of a Triangle

ArrayGeometryMath

Acceptance: 62.5%

#3900Medium

Longest Balanced Substring After One Swap

Hash TablePrefix SumString

Acceptance: 14.2%

#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%

#3905Medium

Multi Source Flood Fill

ArrayBreadth-First SearchMatrix

Acceptance: 56.3%

#3909Medium

Compare Sums of Bitonic Parts

Array

Acceptance: 52.8%

#3913Medium

Sort Vowels by Frequency

CountingSortingString

Acceptance: 61.5%

#3914Medium

Minimum Operations to Make Array Non Decreasing

ArrayGreedy

Acceptance: 54.9%

#3927Medium

Minimize Array Sum Using Divisible Replacements

ArrayGreedyHash Table+2

Acceptance: 32.2%

#3918Medium

Sum of Primes Between Number and Its Reverse

MathNumber Theory

Acceptance: 75.3%

#3926Medium

Count Valid Word Occurrences

ArrayCountingHash Table+1

Acceptance: 48.1%

#3919Medium

Minimum Cost to Move Between Indices

ArrayGreedyPrefix Sum

Acceptance: 49.4%

#3923Medium

Minimum Generations to Target Point

ArrayHash TableSimulation

Acceptance: 42.9%

#3922Medium

Minimum Flips to Make Binary String Coherent

String

Acceptance: 19.9%

#3932Medium

Count K-th Roots in a Range

Binary SearchMath

Acceptance: 24.6%

#3935Medium

Power Update After K-th Largest Insertion I

Acceptance: 68.1%

#3933Medium

Largest Local Values in a Matrix II

ArrayMatrixPrefix Sum

Acceptance: 18.5%

#3941Medium

Password Strength

Hash TableString

Acceptance: 74.5%

#3937Medium

Minimum Operations to Make Array Modulo Alternating I

ArrayEnumeration

Acceptance: 46.5%

#3942Medium

Minimum Operations to Sort a Permutation

Array

Acceptance: 27.8%

#3938Medium

Maximum Path Intersection Sum in a Grid

ArrayDynamic ProgrammingMatrix+1

Acceptance: 25.6%

#3947Medium

Maximum Number of Items From Sale II

ArrayGreedyHeap (Priority Queue)+1

Acceptance: 30.2%

#3946Medium

Maximum Number of Items From Sale I

ArrayDynamic ProgrammingGreedy

Acceptance: 37.3%

#3951Medium

Minimum Energy to Maintain Brightness

ArraySorting

Acceptance: 53.4%

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