Solutions & Explanations

Browse 4,030+ detailed solutions with multiple approaches, code in Python, Java, C++ and more.

4,030 Solutions961 Easy2102 Medium967 Hard

Title	Difficulty	Acceptance	Topics	Solution
2901. Longest Unequal Adjacent Groups Subsequence II	Medium	51.4%	Array Dynamic Programming+1	Read
2902. Count of Sub-Multisets With Bounded Sum	Hard	22.3%	Array Dynamic Programming+2	Read
2903. Find Indices With Index and Value Difference I	Easy	60.2%	Array Two Pointers	Read
2904. Shortest and Lexicographically Smallest Beautiful String	Medium	59.8%	Sliding Window String	Read
2905. Find Indices With Index and Value Difference II	Medium	32.6%	Array Two Pointers	Read
2906. Construct Product Matrix	Medium	51.7%	Array Matrix+1	Read
2907. Maximum Profitable Triplets With Increasing Prices I	Medium	56.2%	Array Binary Indexed Tree+1	Read
2908. Minimum Sum of Mountain Triplets I	Easy	67.3%	Array	Read
2909. Minimum Sum of Mountain Triplets II	Medium	54.5%	Array	Read
2910. Minimum Number of Groups to Create a Valid Assignment	Medium	25.0%	Array Greedy+1	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
2913. Subarrays Distinct Element Sum of Squares I	Easy	80.1%	Array Hash Table	Read
2914. Minimum Number of Changes to Make Binary String Beautiful	Medium	76.4%	String	Read
2915. Length of the Longest Subsequence That Sums to Target	Medium	40.0%	Array Dynamic Programming	Read
2916. Subarrays Distinct Element Sum of Squares II	Hard	23.5%	Array Binary Indexed Tree+2	Read
2917. Find the K-or of an Array	Easy	72.1%	Array Bit Manipulation	Read
2918. Minimum Equal Sum of Two Arrays After Replacing Zeros	Medium	50.2%	Array Greedy	Read
2919. Minimum Increment Operations to Make Array Beautiful	Medium	34.7%	Array Dynamic Programming	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
2922. Market Analysis III	Medium	41.1%	Database	Read
2923. Find Champion I	Easy	73.3%	Array Matrix	Read
2924. Find Champion II	Medium	70.3%	Graph	Read
2925. Maximum Score After Applying Operations on a Tree	Medium	47.2%	Depth-First Search Dynamic Programming+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
2928. Distribute Candies Among Children I	Easy	75.7%	Combinatorics Enumeration+1	Read
2929. Distribute Candies Among Children II	Medium	55.7%	Combinatorics Enumeration+1	Read
2930. Number of Strings Which Can Be Rearranged to Contain Substring	Medium	57.0%	Combinatorics Dynamic Programming+1	Read
2931. Maximum Spending After Buying Items	Hard	60.5%	Array Greedy+3	Read
2932. Maximum Strong Pair XOR I	Easy	76.0%	Array Bit Manipulation+3	Read
2933. High-Access Employees	Medium	47.4%	Array Hash Table+2	Read
2934. Minimum Operations to Maximize Last Elements in Arrays	Medium	43.7%	Array Enumeration	Read
2935. Maximum Strong Pair XOR II	Hard	32.9%	Array Bit Manipulation+3	Read
2936. Number of Equal Numbers Blocks	Medium	62.5%	Array Binary Search+1	Read
2937. Make Three Strings Equal	Easy	45.3%	String	Read
2938. Separate Black and White Balls	Medium	64.0%	Greedy String+1	Read
2939. Maximum Xor Product	Medium	30.3%	Bit Manipulation Greedy+1	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
2942. Find Words Containing Character	Easy	90.4%	Array String	Read
2943. Maximize Area of Square Hole in Grid	Medium	61.9%	Array Sorting	Read
2944. Minimum Number of Coins for Fruits	Medium	49.6%	Array Dynamic Programming+3	Read
2945. Find Maximum Non-decreasing Array Length	Hard	19.2%	Array Binary Search+5	Read
2946. Matrix Similarity After Cyclic Shifts	Easy	74.3%	Array Math+2	Read
2947. Count Beautiful Substrings I	Medium	60.9%	Enumeration Hash Table+4	Read
2948. Make Lexicographically Smallest Array by Swapping Elements	Medium	66.4%	Array Sorting+1	Read
2949. Count Beautiful Substrings II	Hard	27.5%	Hash Table Math+3	Read
2950. Number of Divisible Substrings	Medium	74.6%	Counting Hash Table+2	Read

#2901Medium

Longest Unequal Adjacent Groups Subsequence II

ArrayDynamic ProgrammingString

Acceptance: 51.4%

#2902Hard

Count of Sub-Multisets With Bounded Sum

ArrayDynamic ProgrammingHash Table+1

Acceptance: 22.3%

#2903Easy

Find Indices With Index and Value Difference I

ArrayTwo Pointers

Acceptance: 60.2%

#2904Medium

Shortest and Lexicographically Smallest Beautiful String

Sliding WindowString

Acceptance: 59.8%

#2905Medium

Find Indices With Index and Value Difference II

ArrayTwo Pointers

Acceptance: 32.6%

#2906Medium

Construct Product Matrix

ArrayMatrixPrefix Sum

Acceptance: 51.7%

#2907Medium

Maximum Profitable Triplets With Increasing Prices I

ArrayBinary Indexed TreeSegment Tree

Acceptance: 56.2%

#2908Easy

Minimum Sum of Mountain Triplets I

Array

Acceptance: 67.3%

#2909Medium

Minimum Sum of Mountain Triplets II

Array

Acceptance: 54.5%

#2910Medium

Minimum Number of Groups to Create a Valid Assignment

ArrayGreedyHash Table

Acceptance: 25.0%

#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%

#2913Easy

Subarrays Distinct Element Sum of Squares I

ArrayHash Table

Acceptance: 80.1%

#2914Medium

Minimum Number of Changes to Make Binary String Beautiful

String

Acceptance: 76.4%

#2915Medium

Length of the Longest Subsequence That Sums to Target

ArrayDynamic Programming

Acceptance: 40.0%

#2916Hard

Subarrays Distinct Element Sum of Squares II

ArrayBinary Indexed TreeDynamic Programming+1

Acceptance: 23.5%

#2917Easy

Find the K-or of an Array

ArrayBit Manipulation

Acceptance: 72.1%

#2918Medium

Minimum Equal Sum of Two Arrays After Replacing Zeros

ArrayGreedy

Acceptance: 50.2%

#2919Medium

Minimum Increment Operations to Make Array Beautiful

ArrayDynamic Programming

Acceptance: 34.7%

#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%

#2922Medium

Market Analysis III

Database

Acceptance: 41.1%

#2923Easy

Find Champion I

ArrayMatrix

Acceptance: 73.3%

#2924Medium

Find Champion II

Graph

Acceptance: 70.3%

#2925Medium

Maximum Score After Applying Operations on a Tree

Depth-First SearchDynamic ProgrammingTree

Acceptance: 47.2%

#2926Hard

Maximum Balanced Subsequence Sum

ArrayBinary Indexed TreeBinary Search+2

Acceptance: 25.8%

#2927Hard

Distribute Candies Among Children III

CombinatoricsMath

Acceptance: 57.3%

#2928Easy

Distribute Candies Among Children I

CombinatoricsEnumerationMath

Acceptance: 75.7%

#2929Medium

Distribute Candies Among Children II

CombinatoricsEnumerationMath

Acceptance: 55.7%

#2930Medium

Number of Strings Which Can Be Rearranged to Contain Substring

CombinatoricsDynamic ProgrammingMath

Acceptance: 57.0%

#2931Hard

Maximum Spending After Buying Items

ArrayGreedyHeap (Priority Queue)+2

Acceptance: 60.5%

#2932Easy

Maximum Strong Pair XOR I

ArrayBit ManipulationHash Table+2

Acceptance: 76.0%

#2933Medium

High-Access Employees

ArrayHash TableSorting+1

Acceptance: 47.4%

#2934Medium

Minimum Operations to Maximize Last Elements in Arrays

ArrayEnumeration

Acceptance: 43.7%

#2935Hard

Maximum Strong Pair XOR II

ArrayBit ManipulationHash Table+2

Acceptance: 32.9%

#2936Medium

Number of Equal Numbers Blocks

ArrayBinary SearchInteractive

Acceptance: 62.5%

#2937Easy

Make Three Strings Equal

String

Acceptance: 45.3%

#2938Medium

Separate Black and White Balls

GreedyStringTwo Pointers

Acceptance: 64.0%

#2939Medium

Maximum Xor Product

Bit ManipulationGreedyMath

Acceptance: 30.3%

#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%

#2942Easy

Find Words Containing Character

ArrayString

Acceptance: 90.4%

#2943Medium

Maximize Area of Square Hole in Grid

ArraySorting

Acceptance: 61.9%

#2944Medium

Minimum Number of Coins for Fruits

ArrayDynamic ProgrammingHeap (Priority Queue)+2

Acceptance: 49.6%

#2945Hard

Find Maximum Non-decreasing Array Length

ArrayBinary SearchDynamic Programming+4

Acceptance: 19.2%

#2946Easy

Matrix Similarity After Cyclic Shifts

ArrayMathMatrix+1

Acceptance: 74.3%

#2947Medium

Count Beautiful Substrings I

EnumerationHash TableMath+3

Acceptance: 60.9%

#2948Medium

Make Lexicographically Smallest Array by Swapping Elements

ArraySortingUnion Find

Acceptance: 66.4%

#2949Hard

Count Beautiful Substrings II

Hash TableMathNumber Theory+2

Acceptance: 27.5%

#2950Medium

Number of Divisible Substrings

CountingHash TablePrefix Sum+1

Acceptance: 74.6%

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