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
2627. Debounce	Medium	91.3%		Read
2628. JSON Deep Equal	Medium	38.8%		Read
2631. Group By	Medium	81.0%		Read
2632. Curry	Medium	89.2%		Read
2633. Convert Object to JSON String	Medium	77.4%		Read
2636. Promise Pool	Medium	79.8%		Read
2637. Promise Time Limit	Medium	82.0%		Read
2638. Count the Number of K-Free Subsets	Medium	47.4%	Array Combinatorics+3	Read
2640. Find the Score of All Prefixes of an Array	Medium	72.9%	Array Prefix Sum	Read
2641. Cousins in Binary Tree II	Medium	75.8%	Binary Tree Breadth-First Search+3	Read
2645. Minimum Additions to Make Valid String	Medium	51.0%	Dynamic Programming Greedy+2	Read
2649. Nested Array Generator	Medium	79.3%		Read
2653. Sliding Subarray Beauty	Medium	37.8%	Array Hash Table+1	Read
2654. Minimum Number of Operations to Make All Array Elements Equal to 1	Medium	54.7%	Array Math+1	Read
2655. Find Maximal Uncovered Ranges	Medium	49.9%	Array Sorting	Read
2657. Find the Prefix Common Array of Two Arrays	Medium	88.3%	Array Bit Manipulation+1	Read
2658. Maximum Number of Fish in a Grid	Medium	70.5%	Array Breadth-First Search+3	Read
2661. First Completely Painted Row or Column	Medium	63.9%	Array Hash Table+1	Read
2662. Minimum Cost of a Path With Special Roads	Medium	43.9%	Array Graph+2	Read
2664. The Knight’s Tour	Medium	72.7%	Array Backtracking+1	Read
2671. Frequency Tracker	Medium	31.6%	Design Hash Table	Read
2672. Number of Adjacent Elements With the Same Color	Medium	59.8%	Array	Read
2673. Make Costs of Paths Equal in a Binary Tree	Medium	59.1%	Array Binary Tree+3	Read
2674. Split a Circular Linked List	Medium	78.1%	Linked List Two Pointers	Read
2676. Throttle	Medium	82.9%		Read
2679. Sum in a Matrix	Medium	61.1%	Array Heap (Priority Queue)+3	Read
2680. Maximum OR	Medium	43.5%	Array Bit Manipulation+2	Read
2683. Neighboring Bitwise XOR	Medium	79.8%	Array Bit Manipulation	Read
2684. Maximum Number of Moves in a Grid	Medium	58.6%	Array Dynamic Programming+1	Read
2685. Count the Number of Complete Components	Medium	80.8%	Breadth-First Search Depth-First Search+2	Read
2686. Immediate Food Delivery III	Medium	68.2%	Database	Read
2688. Find Active Users	Medium	43.4%	Database	Read
2692. Make Object Immutable	Medium	64.5%		Read
2693. Call Function with Custom Context	Medium	79.0%		Read
2694. Event Emitter	Medium	74.1%		Read
2698. Find the Punishment Number of an Integer	Medium	81.7%	Backtracking Math	Read
2700. Differences Between Two Objects	Medium	75.2%		Read
2705. Compact Object	Medium	65.8%		Read
2707. Extra Characters in a String	Medium	57.4%	Array Dynamic Programming+3	Read
2708. Maximum Strength of a Group	Medium	25.6%	Array Backtracking+5	Read
2711. Difference of Number of Distinct Values on Diagonals	Medium	67.8%	Array Hash Table+1	Read
2712. Minimum Cost to Make All Characters Equal	Medium	54.9%	Dynamic Programming Greedy+1	Read
2718. Sum of Matrix After Queries	Medium	32.5%	Array Hash Table	Read
2721. Execute Asynchronous Functions in Parallel	Medium	76.0%		Read
2722. Join Two Arrays by ID	Medium	55.4%		Read
2730. Find the Longest Semi-Repetitive Substring	Medium	39.3%	Sliding Window String	Read
2731. Movement of Robots	Medium	28.1%	Array Brainteaser+2	Read
2734. Lexicographically Smallest String After Substring Operation	Medium	35.2%	Greedy String	Read
2735. Collecting Chocolates	Medium	35.4%	Array Enumeration	Read
2737. Find the Closest Marked Node	Medium	65.4%	Array Graph+2	Read

#2627Medium

Debounce

Acceptance: 91.3%

#2628Medium

JSON Deep Equal

Acceptance: 38.8%

#2631Medium

Group By

Acceptance: 81.0%

#2632Medium

Curry

Acceptance: 89.2%

#2633Medium

Convert Object to JSON String

Acceptance: 77.4%

#2636Medium

Promise Pool

Acceptance: 79.8%

#2637Medium

Promise Time Limit

Acceptance: 82.0%

#2638Medium

Count the Number of K-Free Subsets

ArrayCombinatoricsDynamic Programming+2

Acceptance: 47.4%

#2640Medium

Find the Score of All Prefixes of an Array

ArrayPrefix Sum

Acceptance: 72.9%

#2641Medium

Cousins in Binary Tree II

Binary TreeBreadth-First SearchDepth-First Search+2

Acceptance: 75.8%

#2645Medium

Minimum Additions to Make Valid String

Dynamic ProgrammingGreedyStack+1

Acceptance: 51.0%

#2649Medium

Nested Array Generator

Acceptance: 79.3%

#2653Medium

Sliding Subarray Beauty

ArrayHash TableSliding Window

Acceptance: 37.8%

#2654Medium

Minimum Number of Operations to Make All Array Elements Equal to 1

ArrayMathNumber Theory

Acceptance: 54.7%

#2655Medium

Find Maximal Uncovered Ranges

ArraySorting

Acceptance: 49.9%

#2657Medium

Find the Prefix Common Array of Two Arrays

ArrayBit ManipulationHash Table

Acceptance: 88.3%

#2658Medium

Maximum Number of Fish in a Grid

ArrayBreadth-First SearchDepth-First Search+2

Acceptance: 70.5%

#2661Medium

First Completely Painted Row or Column

ArrayHash TableMatrix

Acceptance: 63.9%

#2662Medium

Minimum Cost of a Path With Special Roads

ArrayGraphHeap (Priority Queue)+1

Acceptance: 43.9%

#2664Medium

The Knight’s Tour

ArrayBacktrackingMatrix

Acceptance: 72.7%

#2671Medium

Frequency Tracker

DesignHash Table

Acceptance: 31.6%

#2672Medium

Number of Adjacent Elements With the Same Color

Array

Acceptance: 59.8%

#2673Medium

Make Costs of Paths Equal in a Binary Tree

ArrayBinary TreeDynamic Programming+2

Acceptance: 59.1%

#2674Medium

Split a Circular Linked List

Linked ListTwo Pointers

Acceptance: 78.1%

#2676Medium

Throttle

Acceptance: 82.9%

#2679Medium

Sum in a Matrix

ArrayHeap (Priority Queue)Matrix+2

Acceptance: 61.1%

#2680Medium

Maximum OR

ArrayBit ManipulationGreedy+1

Acceptance: 43.5%

#2683Medium

Neighboring Bitwise XOR

ArrayBit Manipulation

Acceptance: 79.8%

#2684Medium

Maximum Number of Moves in a Grid

ArrayDynamic ProgrammingMatrix

Acceptance: 58.6%

#2685Medium

Count the Number of Complete Components

Breadth-First SearchDepth-First SearchGraph+1

Acceptance: 80.8%

#2686Medium

Immediate Food Delivery III

Database

Acceptance: 68.2%

#2688Medium

Find Active Users

Database

Acceptance: 43.4%

#2692Medium

Make Object Immutable

Acceptance: 64.5%

#2693Medium

Call Function with Custom Context

Acceptance: 79.0%

#2694Medium

Event Emitter

Acceptance: 74.1%

#2698Medium

Find the Punishment Number of an Integer

BacktrackingMath

Acceptance: 81.7%

#2700Medium

Differences Between Two Objects

Acceptance: 75.2%

#2705Medium

Compact Object

Acceptance: 65.8%

#2707Medium

Extra Characters in a String

ArrayDynamic ProgrammingHash Table+2

Acceptance: 57.4%

#2708Medium

Maximum Strength of a Group

ArrayBacktrackingBit Manipulation+4

Acceptance: 25.6%

#2711Medium

Difference of Number of Distinct Values on Diagonals

ArrayHash TableMatrix

Acceptance: 67.8%

#2712Medium

Minimum Cost to Make All Characters Equal

Dynamic ProgrammingGreedyString

Acceptance: 54.9%

#2718Medium

Sum of Matrix After Queries

ArrayHash Table

Acceptance: 32.5%

#2721Medium

Execute Asynchronous Functions in Parallel

Acceptance: 76.0%

#2722Medium

Join Two Arrays by ID

Acceptance: 55.4%

#2730Medium

Find the Longest Semi-Repetitive Substring

Sliding WindowString

Acceptance: 39.3%

#2731Medium

Movement of Robots

ArrayBrainteaserPrefix Sum+1

Acceptance: 28.1%

#2734Medium

Lexicographically Smallest String After Substring Operation

GreedyString

Acceptance: 35.2%

#2735Medium

Collecting Chocolates

ArrayEnumeration

Acceptance: 35.4%

#2737Medium

Find the Closest Marked Node

ArrayGraphHeap (Priority Queue)+1

Acceptance: 65.4%

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Master DSA with Step-by-Step Solutions

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