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
2738. Count Occurrences in Text	Medium	55.6%	Database	Read
2740. Find the Value of the Partition	Medium	64.9%	Array Sorting	Read
2741. Special Permutations	Medium	29.4%	Array Bit Manipulation+2	Read
2743. Count Substrings Without Repeating Character	Medium	75.9%	Hash Table Sliding Window+1	Read
2745. Construct the Longest New String	Medium	55.3%	Brainteaser Dynamic Programming+2	Read
2746. Decremental String Concatenation	Medium	28.2%	Array Dynamic Programming+1	Read
2747. Count Zero Request Servers	Medium	36.3%	Array Hash Table+2	Read
2749. Minimum Operations to Make the Integer Zero	Medium	58.2%	Bit Manipulation Brainteaser	Read
2750. Ways to Split Array Into Good Subarrays	Medium	34.9%	Array Dynamic Programming+1	Read
2754. Bind Function to Context	Medium	87.0%		Read
2755. Deep Merge of Two Objects	Medium	66.4%		Read
2757. Generate Circular Array Values	Medium	73.3%		Read
2761. Prime Pairs With Target Sum	Medium	38.4%	Array Enumeration+2	Read
2762. Continuous Subarrays	Medium	58.0%	Array Heap (Priority Queue)+4	Read
2764. Is Array a Preorder of Some ‌Binary Tree	Medium	67.8%	Binary Tree Depth-First Search+2	Read
2766. Relocate Marbles	Medium	51.9%	Array Hash Table+2	Read
2767. Partition String Into Minimum Beautiful Substrings	Medium	54.0%	Backtracking Dynamic Programming+2	Read
2768. Number of Black Blocks	Medium	42.2%	Array Enumeration+1	Read
2770. Maximum Number of Jumps to Reach the Last Index	Medium	51.2%	Array Dynamic Programming	Read
2771. Longest Non-decreasing Subarray From Two Arrays	Medium	31.1%	Array Dynamic Programming	Read
2772. Apply Operations to Make All Array Elements Equal to Zero	Medium	33.5%	Array Prefix Sum	Read
2773. Height of Special Binary Tree	Medium	74.6%	Binary Tree Breadth-First Search+2	Read
2775. Undefined to Null	Medium	69.6%		Read
2776. Convert Callback Based Function to Promise Based Function	Medium	92.1%		Read
2777. Date Range Generator	Medium	80.4%		Read
2779. Maximum Beauty of an Array After Applying Operation	Medium	58.4%	Array Binary Search+2	Read
2780. Minimum Index of a Valid Split	Medium	75.5%	Array Hash Table+1	Read
2782. Number of Unique Categories	Medium	83.8%	Counting Interactive+1	Read
2783. Flight Occupancy and Waitlist Analysis	Medium	38.0%	Database	Read
2785. Sort Vowels in a String	Medium	83.4%	Sorting String	Read
2786. Visit Array Positions to Maximize Score	Medium	37.5%	Array Dynamic Programming	Read
2787. Ways to Express an Integer as Sum of Powers	Medium	49.8%	Dynamic Programming	Read
2789. Largest Element in an Array after Merge Operations	Medium	48.3%	Array Greedy	Read
2795. Parallel Execution of Promises for Individual Results Retrieval	Medium	88.7%		Read
2799. Count Complete Subarrays in an Array	Medium	75.9%	Array Hash Table+1	Read
2800. Shortest String That Contains Three Strings	Medium	32.2%	Enumeration Greedy+1	Read
2802. Find The K-th Lucky Number	Medium	76.1%	Bit Manipulation Math+1	Read
2805. Custom Interval	Medium	81.7%		Read
2807. Insert Greatest Common Divisors in Linked List	Medium	91.4%	Linked List Math+1	Read
2808. Minimum Seconds to Equalize a Circular Array	Medium	28.5%	Array Hash Table	Read
2811. Check if it is Possible to Split Array	Medium	34.5%	Array Dynamic Programming+1	Read
2812. Find the Safest Path in a Grid	Medium	57.0%	Array Binary Search+3	Read
2816. Double a Number Represented as a Linked List	Medium	61.4%	Linked List Math+1	Read
2817. Minimum Absolute Difference Between Elements With Constraint	Medium	38.0%	Array Binary Search+1	Read
2820. Election Results	Medium	66.7%		Read
2821. Delay the Resolution of Each Promise	Medium	68.4%		Read
2823. Deep Object Filter	Medium	54.6%		Read
2825. Make String a Subsequence Using Cyclic Increments	Medium	65.7%	String Two Pointers	Read
2826. Sorting Three Groups	Medium	43.5%	Array Binary Search+1	Read
2829. Determine the Minimum Sum of a k-avoiding Array	Medium	61.0%	Greedy Math	Read

#2738Medium

Count Occurrences in Text

Database

Acceptance: 55.6%

#2740Medium

Find the Value of the Partition

ArraySorting

Acceptance: 64.9%

#2741Medium

Special Permutations

ArrayBit ManipulationBitmask+1

Acceptance: 29.4%

#2743Medium

Count Substrings Without Repeating Character

Hash TableSliding WindowString

Acceptance: 75.9%

#2745Medium

Construct the Longest New String

BrainteaserDynamic ProgrammingGreedy+1

Acceptance: 55.3%

#2746Medium

Decremental String Concatenation

ArrayDynamic ProgrammingString

Acceptance: 28.2%

#2747Medium

Count Zero Request Servers

ArrayHash TableSliding Window+1

Acceptance: 36.3%

#2749Medium

Minimum Operations to Make the Integer Zero

Bit ManipulationBrainteaser

Acceptance: 58.2%

#2750Medium

Ways to Split Array Into Good Subarrays

ArrayDynamic ProgrammingMath

Acceptance: 34.9%

#2754Medium

Bind Function to Context

Acceptance: 87.0%

#2755Medium

Deep Merge of Two Objects

Acceptance: 66.4%

#2757Medium

Generate Circular Array Values

Acceptance: 73.3%

#2761Medium

Prime Pairs With Target Sum

ArrayEnumerationMath+1

Acceptance: 38.4%

#2762Medium

Continuous Subarrays

ArrayHeap (Priority Queue)Monotonic Queue+3

Acceptance: 58.0%

#2764Medium

Is Array a Preorder of Some ‌Binary Tree

Binary TreeDepth-First SearchStack+1

Acceptance: 67.8%

#2766Medium

Relocate Marbles

ArrayHash TableSimulation+1

Acceptance: 51.9%

#2767Medium

Partition String Into Minimum Beautiful Substrings

BacktrackingDynamic ProgrammingHash Table+1

Acceptance: 54.0%

#2768Medium

Number of Black Blocks

ArrayEnumerationHash Table

Acceptance: 42.2%

#2770Medium

Maximum Number of Jumps to Reach the Last Index

ArrayDynamic Programming

Acceptance: 51.2%

#2771Medium

Longest Non-decreasing Subarray From Two Arrays

ArrayDynamic Programming

Acceptance: 31.1%

#2772Medium

Apply Operations to Make All Array Elements Equal to Zero

ArrayPrefix Sum

Acceptance: 33.5%

#2773Medium

Height of Special Binary Tree

Binary TreeBreadth-First SearchDepth-First Search+1

Acceptance: 74.6%

#2775Medium

Undefined to Null

Acceptance: 69.6%

#2776Medium

Convert Callback Based Function to Promise Based Function

Acceptance: 92.1%

#2777Medium

Date Range Generator

Acceptance: 80.4%

#2779Medium

Maximum Beauty of an Array After Applying Operation

ArrayBinary SearchSliding Window+1

Acceptance: 58.4%

#2780Medium

Minimum Index of a Valid Split

ArrayHash TableSorting

Acceptance: 75.5%

#2782Medium

Number of Unique Categories

CountingInteractiveUnion Find

Acceptance: 83.8%

#2783Medium

Flight Occupancy and Waitlist Analysis

Database

Acceptance: 38.0%

#2785Medium

Sort Vowels in a String

SortingString

Acceptance: 83.4%

#2786Medium

Visit Array Positions to Maximize Score

ArrayDynamic Programming

Acceptance: 37.5%

#2787Medium

Ways to Express an Integer as Sum of Powers

Dynamic Programming

Acceptance: 49.8%

#2789Medium

Largest Element in an Array after Merge Operations

ArrayGreedy

Acceptance: 48.3%

#2795Medium

Parallel Execution of Promises for Individual Results Retrieval

Acceptance: 88.7%

#2799Medium

Count Complete Subarrays in an Array

ArrayHash TableSliding Window

Acceptance: 75.9%

#2800Medium

Shortest String That Contains Three Strings

EnumerationGreedyString

Acceptance: 32.2%

#2802Medium

Find The K-th Lucky Number

Bit ManipulationMathString

Acceptance: 76.1%

#2805Medium

Custom Interval

Acceptance: 81.7%

#2807Medium

Insert Greatest Common Divisors in Linked List

Linked ListMathNumber Theory

Acceptance: 91.4%

#2808Medium

Minimum Seconds to Equalize a Circular Array

ArrayHash Table

Acceptance: 28.5%

#2811Medium

Check if it is Possible to Split Array

ArrayDynamic ProgrammingGreedy

Acceptance: 34.5%

#2812Medium

Find the Safest Path in a Grid

ArrayBinary SearchBreadth-First Search+2

Acceptance: 57.0%

#2816Medium

Double a Number Represented as a Linked List

Linked ListMathStack

Acceptance: 61.4%

#2817Medium

Minimum Absolute Difference Between Elements With Constraint

ArrayBinary SearchOrdered Set

Acceptance: 38.0%

#2820Medium

Election Results

Acceptance: 66.7%

#2821Medium

Delay the Resolution of Each Promise

Acceptance: 68.4%

#2823Medium

Deep Object Filter

Acceptance: 54.6%

#2825Medium

Make String a Subsequence Using Cyclic Increments

StringTwo Pointers

Acceptance: 65.7%

#2826Medium

Sorting Three Groups

ArrayBinary SearchDynamic Programming

Acceptance: 43.5%

#2829Medium

Determine the Minimum Sum of a k-avoiding Array

GreedyMath

Acceptance: 61.0%

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