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
2732. Find a Good Subset of the Matrix	Hard	45.4%	Array Bit Manipulation+2	Read
2736. Maximum Sum Queries	Hard	31.2%	Array Binary Indexed Tree+5	Read
2742. Painting the Walls	Hard	49.0%	Array Dynamic Programming	Read
2751. Robot Collisions	Hard	61.6%	Array Simulation+2	Read
2752. Customers with Maximum Number of Transactions on Consecutive Days	Hard	39.6%	Database	Read
2753. Count Houses in a Circular Street II	Hard	61.5%		Read
2756. Query Batching	Hard	63.0%		Read
2759. Convert JSON String to Object	Hard	61.7%		Read
2763. Sum of Imbalance Numbers of All Subarrays	Hard	43.8%	Array Hash Table+1	Read
2781. Length of the Longest Valid Substring	Hard	38.3%	Array Hash Table+2	Read
2790. Maximum Number of Groups With Increasing Length	Hard	23.0%	Array Binary Search+3	Read
2791. Count Paths That Can Form a Palindrome in a Tree	Hard	52.0%	Bit Manipulation Bitmask+3	Read
2792. Count Nodes That Are Great Enough	Hard	56.5%	Binary Tree Depth-First Search+2	Read
2793. Status of Flight Tickets	Hard	76.1%		Read
2801. Count Stepping Numbers in Range	Hard	29.9%	Dynamic Programming String	Read
2809. Minimum Time to Make Array Sum At Most x	Hard	28.1%	Array Dynamic Programming+1	Read
2813. Maximum Elegance of a K-Length Subsequence	Hard	29.2%	Array Greedy+4	Read
2814. Minimum Time Takes to Reach Destination Without Drowning	Hard	54.7%	Array Breadth-First Search+1	Read
2818. Apply Operations to Maximize Score	Hard	53.7%	Array Greedy+4	Read
2819. Minimum Relative Loss After Buying Chocolates	Hard	47.4%	Array Binary Search+2	Read
2827. Number of Beautiful Integers in the Range	Hard	23.1%	Dynamic Programming Math	Read
2835. Minimum Operations to Form Subsequence With Target Sum	Hard	32.5%	Array Bit Manipulation+1	Read
2836. Maximize Value of Function in a Ball Passing Game	Hard	31.3%	Array Bit Manipulation+1	Read
2842. Count K-Subsequences of a String With Maximum Beauty	Hard	30.2%	Combinatorics Greedy+3	Read
2846. Minimum Edge Weight Equilibrium Queries in a Tree	Hard	46.1%	Array Graph+2	Read
2851. String Transformation	Hard	27.4%	Dynamic Programming Math+2	Read
2858. Minimum Edge Reversals So Every Node Is Reachable	Hard	59.6%	Breadth-First Search Depth-First Search+2	Read
2862. Maximum Element-Sum of a Complete Subset of Indices	Hard	42.3%	Array Math+1	Read
2867. Count Valid Paths in a Tree	Hard	36.2%	Depth-First Search Dynamic Programming+3	Read
2868. The Wording Game	Hard	53.6%	Array Game Theory+4	Read
2872. Maximum Number of K-Divisible Components	Hard	74.1%	Depth-First Search Tree	Read
2876. Count Visited Nodes in a Directed Graph	Hard	31.6%	Dynamic Programming Graph+1	Read
2897. Apply Operations on Array to Maximize Sum of Squares	Hard	43.5%	Array Bit Manipulation+2	Read
2902. Count of Sub-Multisets With Bounded Sum	Hard	22.3%	Array Dynamic Programming+2	Read
2911. Minimum Changes to Make K Semi-palindromes	Hard	35.3%	Dynamic Programming String+1	Read
2912. Number of Ways to Reach Destination in the Grid	Hard	57.7%	Combinatorics Dynamic Programming+1	Read
2916. Subarrays Distinct Element Sum of Squares II	Hard	23.5%	Array Binary Indexed Tree+2	Read
2920. Maximum Points After Collecting Coins From All Nodes	Hard	36.6%	Array Bit Manipulation+3	Read
2921. Maximum Profitable Triplets With Increasing Prices II	Hard	46.1%	Array Binary Indexed Tree+1	Read
2926. Maximum Balanced Subsequence Sum	Hard	25.8%	Array Binary Indexed Tree+3	Read
2927. Distribute Candies Among Children III	Hard	57.3%	Combinatorics Math	Read
2931. Maximum Spending After Buying Items	Hard	60.5%	Array Greedy+3	Read
2935. Maximum Strong Pair XOR II	Hard	32.9%	Array Bit Manipulation+3	Read
2940. Find Building Where Alice and Bob Can Meet	Hard	52.3%	Array Binary Indexed Tree+5	Read
2941. Maximum GCD-Sum of a Subarray	Hard	39.9%	Array Binary Search+2	Read
2945. Find Maximum Non-decreasing Array Length	Hard	19.2%	Array Binary Search+5	Read
2949. Count Beautiful Substrings II	Hard	27.5%	Hash Table Math+3	Read
2953. Count Complete Substrings	Hard	31.3%	Hash Table Sliding Window+1	Read
2954. Count the Number of Infection Sequences	Hard	36.7%	Array Combinatorics+1	Read
2959. Number of Possible Sets of Closing Branches	Hard	50.6%	Bit Manipulation Enumeration+3	Read

#2732Hard

Find a Good Subset of the Matrix

ArrayBit ManipulationHash Table+1

Acceptance: 45.4%

#2736Hard

Maximum Sum Queries

ArrayBinary Indexed TreeBinary Search+4

Acceptance: 31.2%

#2742Hard

Painting the Walls

ArrayDynamic Programming

Acceptance: 49.0%

#2751Hard

Robot Collisions

ArraySimulationSorting+1

Acceptance: 61.6%

#2752Hard

Customers with Maximum Number of Transactions on Consecutive Days

Database

Acceptance: 39.6%

#2753Hard

Count Houses in a Circular Street II

Acceptance: 61.5%

#2756Hard

Query Batching

Acceptance: 63.0%

#2759Hard

Convert JSON String to Object

Acceptance: 61.7%

#2763Hard

Sum of Imbalance Numbers of All Subarrays

ArrayHash TableOrdered Set

Acceptance: 43.8%

#2781Hard

Length of the Longest Valid Substring

ArrayHash TableSliding Window+1

Acceptance: 38.3%

#2790Hard

Maximum Number of Groups With Increasing Length

ArrayBinary SearchGreedy+2

Acceptance: 23.0%

#2791Hard

Count Paths That Can Form a Palindrome in a Tree

Bit ManipulationBitmaskDepth-First Search+2

Acceptance: 52.0%

#2792Hard

Count Nodes That Are Great Enough

Binary TreeDepth-First SearchDivide and Conquer+1

Acceptance: 56.5%

#2793Hard

Status of Flight Tickets

Acceptance: 76.1%

#2801Hard

Count Stepping Numbers in Range

Dynamic ProgrammingString

Acceptance: 29.9%

#2809Hard

Minimum Time to Make Array Sum At Most x

ArrayDynamic ProgrammingSorting

Acceptance: 28.1%

#2813Hard

Maximum Elegance of a K-Length Subsequence

ArrayGreedyHash Table+3

Acceptance: 29.2%

#2814Hard

Minimum Time Takes to Reach Destination Without Drowning

ArrayBreadth-First SearchMatrix

Acceptance: 54.7%

#2818Hard

Apply Operations to Maximize Score

ArrayGreedyMath+3

Acceptance: 53.7%

#2819Hard

Minimum Relative Loss After Buying Chocolates

ArrayBinary SearchPrefix Sum+1

Acceptance: 47.4%

#2827Hard

Number of Beautiful Integers in the Range

Dynamic ProgrammingMath

Acceptance: 23.1%

#2835Hard

Minimum Operations to Form Subsequence With Target Sum

ArrayBit ManipulationGreedy

Acceptance: 32.5%

#2836Hard

Maximize Value of Function in a Ball Passing Game

ArrayBit ManipulationDynamic Programming

Acceptance: 31.3%

#2842Hard

Count K-Subsequences of a String With Maximum Beauty

CombinatoricsGreedyHash Table+2

Acceptance: 30.2%

#2846Hard

Minimum Edge Weight Equilibrium Queries in a Tree

ArrayGraphStrongly Connected Component+1

Acceptance: 46.1%

#2851Hard

String Transformation

Dynamic ProgrammingMathString+1

Acceptance: 27.4%

#2858Hard

Minimum Edge Reversals So Every Node Is Reachable

Breadth-First SearchDepth-First SearchDynamic Programming+1

Acceptance: 59.6%

#2862Hard

Maximum Element-Sum of a Complete Subset of Indices

ArrayMathNumber Theory

Acceptance: 42.3%

#2867Hard

Count Valid Paths in a Tree

Depth-First SearchDynamic ProgrammingMath+2

Acceptance: 36.2%

#2868Hard

The Wording Game

ArrayGame TheoryGreedy+3

Acceptance: 53.6%

#2872Hard

Maximum Number of K-Divisible Components

Depth-First SearchTree

Acceptance: 74.1%

#2876Hard

Count Visited Nodes in a Directed Graph

Dynamic ProgrammingGraphMemoization

Acceptance: 31.6%

#2897Hard

Apply Operations on Array to Maximize Sum of Squares

ArrayBit ManipulationGreedy+1

Acceptance: 43.5%

#2902Hard

Count of Sub-Multisets With Bounded Sum

ArrayDynamic ProgrammingHash Table+1

Acceptance: 22.3%

#2911Hard

Minimum Changes to Make K Semi-palindromes

Dynamic ProgrammingStringTwo Pointers

Acceptance: 35.3%

#2912Hard

Number of Ways to Reach Destination in the Grid

CombinatoricsDynamic ProgrammingMath

Acceptance: 57.7%

#2916Hard

Subarrays Distinct Element Sum of Squares II

ArrayBinary Indexed TreeDynamic Programming+1

Acceptance: 23.5%

#2920Hard

Maximum Points After Collecting Coins From All Nodes

ArrayBit ManipulationDepth-First Search+2

Acceptance: 36.6%

#2921Hard

Maximum Profitable Triplets With Increasing Prices II

ArrayBinary Indexed TreeSegment Tree

Acceptance: 46.1%

#2926Hard

Maximum Balanced Subsequence Sum

ArrayBinary Indexed TreeBinary Search+2

Acceptance: 25.8%

#2927Hard

Distribute Candies Among Children III

CombinatoricsMath

Acceptance: 57.3%

#2931Hard

Maximum Spending After Buying Items

ArrayGreedyHeap (Priority Queue)+2

Acceptance: 60.5%

#2935Hard

Maximum Strong Pair XOR II

ArrayBit ManipulationHash Table+2

Acceptance: 32.9%

#2940Hard

Find Building Where Alice and Bob Can Meet

ArrayBinary Indexed TreeBinary Search+4

Acceptance: 52.3%

#2941Hard

Maximum GCD-Sum of a Subarray

ArrayBinary SearchMath+1

Acceptance: 39.9%

#2945Hard

Find Maximum Non-decreasing Array Length

ArrayBinary SearchDynamic Programming+4

Acceptance: 19.2%

#2949Hard

Count Beautiful Substrings II

Hash TableMathNumber Theory+2

Acceptance: 27.5%

#2953Hard

Count Complete Substrings

Hash TableSliding WindowString

Acceptance: 31.3%

#2954Hard

Count the Number of Infection Sequences

ArrayCombinatoricsMath

Acceptance: 36.7%

#2959Hard

Number of Possible Sets of Closing Branches

Bit ManipulationEnumerationGraph+2

Acceptance: 50.6%

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