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
2939. Maximum Xor Product	Medium	30.3%	Bit Manipulation Greedy+1	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
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
2950. Number of Divisible Substrings	Medium	74.6%	Counting Hash Table+2	Read
2952. Minimum Number of Coins to be Added	Medium	57.9%	Array Greedy+1	Read
2955. Number of Same-End Substrings	Medium	61.6%	Array Counting+3	Read
2957. Remove Adjacent Almost-Equal Characters	Medium	53.6%	Dynamic Programming Greedy+1	Read
2958. Length of Longest Subarray With at Most K Frequency	Medium	60.4%	Array Hash Table+1	Read
2961. Double Modular Exponentiation	Medium	47.9%	Array Math+1	Read
2962. Count Subarrays Where Max Element Appears at Least K Times	Medium	62.4%	Array Sliding Window	Read
2964. Number of Divisible Triplet Sums	Medium	67.5%	Array Hash Table	Read
2966. Divide Array Into Arrays With Max Difference	Medium	79.0%	Array Greedy+1	Read
2967. Minimum Cost to Make Array Equalindromic	Medium	23.4%	Array Binary Search+3	Read
2971. Find Polygon With the Largest Perimeter	Medium	65.7%	Array Greedy+2	Read
2975. Maximum Square Area by Removing Fences From a Field	Medium	49.5%	Array Enumeration+1	Read
2976. Minimum Cost to Convert String I	Medium	63.2%	Array Graph+2	Read
2978. Symmetric Coordinates	Medium	40.8%	Database	Read
2979. Most Expensive Item That Can Not Be Bought	Medium	80.2%	Dynamic Programming Math+1	Read
2981. Find Longest Special Substring That Occurs Thrice I	Medium	61.9%	Binary Search Counting+3	Read
2982. Find Longest Special Substring That Occurs Thrice II	Medium	39.2%	Binary Search Counting+3	Read
2984. Find Peak Calling Hours for Each City	Medium	61.1%	Database	Read
2986. Find Third Transaction	Medium	53.0%	Database	Read
2988. Manager of the Largest Department	Medium	79.4%	Database	Read
2989. Class Performance	Medium	89.9%	Database	Read
2992. Number of Self-Divisible Permutations	Medium	72.0%	Array Backtracking+3	Read
2993. Friday Purchases I	Medium	79.1%	Database	Read
2997. Minimum Number of Operations to Make Array XOR Equal to K	Medium	85.1%	Array Bit Manipulation	Read
2998. Minimum Number of Operations to Make X and Y Equal	Medium	48.4%	Breadth-First Search Dynamic Programming+1	Read
3001. Minimum Moves to Capture The Queen	Medium	22.3%	Array Enumeration	Read
3002. Maximum Size of a Set After Removals	Medium	46.2%	Array Greedy+1	Read
3004. Maximum Subtree of the Same Color	Medium	59.2%	Array Depth-First Search+2	Read
3006. Find Beautiful Indices in the Given Array I	Medium	41.2%	Binary Search Hash Function+4	Read
3007. Maximum Number That Sum of the Prices Is Less Than or Equal to K	Medium	38.4%	Binary Search Bit Manipulation+1	Read
3011. Find if Array Can Be Sorted	Medium	66.4%	Array Bit Manipulation+1	Read
3012. Minimize Length of Array Using Operations	Medium	35.7%	Array Greedy+2	Read
3015. Count the Number of Houses at a Certain Distance I	Medium	58.2%	Breadth-First Search Graph+1	Read
3016. Minimum Number of Pushes to Type Word II	Medium	83.2%	Counting Greedy+3	Read
3020. Find the Maximum Number of Elements in Subset	Medium	42.2%	Array Enumeration+1	Read
3021. Alice and Bob Playing Flower Game	Medium	60.2%	Math	Read
3023. Find Pattern in Infinite Stream I	Medium	57.5%	Array Hash Function+3	Read
3025. Find the Number of Ways to Place People I	Medium	64.0%	Array Enumeration+3	Read
3026. Maximum Good Subarray Sum	Medium	22.1%	Array Hash Table+1	Read
3029. Minimum Time to Revert Word to Initial State I	Medium	42.4%	Hash Function Rolling Hash+2	Read
3030. Find the Grid of Region Average	Medium	43.0%	Array Matrix	Read
3034. Number of Subarrays That Match a Pattern I	Medium	67.9%	Array Hash Function+2	Read
3035. Maximum Palindromes After Operations	Medium	47.2%	Array Counting+4	Read
3039. Apply Operations to Make String Empty	Medium	57.5%	Array Counting+2	Read
3040. Maximum Number of Operations With the Same Score II	Medium	34.1%	Array Dynamic Programming+1	Read

#2939Medium

Maximum Xor Product

Bit ManipulationGreedyMath

Acceptance: 30.3%

#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%

#2947Medium

Count Beautiful Substrings I

EnumerationHash TableMath+3

Acceptance: 60.9%

#2948Medium

Make Lexicographically Smallest Array by Swapping Elements

ArraySortingUnion Find

Acceptance: 66.4%

#2950Medium

Number of Divisible Substrings

CountingHash TablePrefix Sum+1

Acceptance: 74.6%

#2952Medium

Minimum Number of Coins to be Added

ArrayGreedySorting

Acceptance: 57.9%

#2955Medium

Number of Same-End Substrings

ArrayCountingHash Table+2

Acceptance: 61.6%

#2957Medium

Remove Adjacent Almost-Equal Characters

Dynamic ProgrammingGreedyString

Acceptance: 53.6%

#2958Medium

Length of Longest Subarray With at Most K Frequency

ArrayHash TableSliding Window

Acceptance: 60.4%

#2961Medium

Double Modular Exponentiation

ArrayMathSimulation

Acceptance: 47.9%

#2962Medium

Count Subarrays Where Max Element Appears at Least K Times

ArraySliding Window

Acceptance: 62.4%

#2964Medium

Number of Divisible Triplet Sums

ArrayHash Table

Acceptance: 67.5%

#2966Medium

Divide Array Into Arrays With Max Difference

ArrayGreedySorting

Acceptance: 79.0%

#2967Medium

Minimum Cost to Make Array Equalindromic

ArrayBinary SearchGreedy+2

Acceptance: 23.4%

#2971Medium

Find Polygon With the Largest Perimeter

ArrayGreedyPrefix Sum+1

Acceptance: 65.7%

#2975Medium

Maximum Square Area by Removing Fences From a Field

ArrayEnumerationHash Table

Acceptance: 49.5%

#2976Medium

Minimum Cost to Convert String I

ArrayGraphShortest Path+1

Acceptance: 63.2%

#2978Medium

Symmetric Coordinates

Database

Acceptance: 40.8%

#2979Medium

Most Expensive Item That Can Not Be Bought

Dynamic ProgrammingMathNumber Theory

Acceptance: 80.2%

#2981Medium

Find Longest Special Substring That Occurs Thrice I

Binary SearchCountingHash Table+2

Acceptance: 61.9%

#2982Medium

Find Longest Special Substring That Occurs Thrice II

Binary SearchCountingHash Table+2

Acceptance: 39.2%

#2984Medium

Find Peak Calling Hours for Each City

Database

Acceptance: 61.1%

#2986Medium

Find Third Transaction

Database

Acceptance: 53.0%

#2988Medium

Manager of the Largest Department

Database

Acceptance: 79.4%

#2989Medium

Class Performance

Database

Acceptance: 89.9%

#2992Medium

Number of Self-Divisible Permutations

ArrayBacktrackingBit Manipulation+2

Acceptance: 72.0%

#2993Medium

Friday Purchases I

Database

Acceptance: 79.1%

#2997Medium

Minimum Number of Operations to Make Array XOR Equal to K

ArrayBit Manipulation

Acceptance: 85.1%

#2998Medium

Minimum Number of Operations to Make X and Y Equal

Breadth-First SearchDynamic ProgrammingMemoization

Acceptance: 48.4%

#3001Medium

Minimum Moves to Capture The Queen

ArrayEnumeration

Acceptance: 22.3%

#3002Medium

Maximum Size of a Set After Removals

ArrayGreedyHash Table

Acceptance: 46.2%

#3004Medium

Maximum Subtree of the Same Color

ArrayDepth-First SearchDynamic Programming+1

Acceptance: 59.2%

#3006Medium

Find Beautiful Indices in the Given Array I

Binary SearchHash FunctionRolling Hash+3

Acceptance: 41.2%

#3007Medium

Maximum Number That Sum of the Prices Is Less Than or Equal to K

Binary SearchBit ManipulationDynamic Programming

Acceptance: 38.4%

#3011Medium

Find if Array Can Be Sorted

ArrayBit ManipulationSorting

Acceptance: 66.4%

#3012Medium

Minimize Length of Array Using Operations

ArrayGreedyMath+1

Acceptance: 35.7%

#3015Medium

Count the Number of Houses at a Certain Distance I

Breadth-First SearchGraphPrefix Sum

Acceptance: 58.2%

#3016Medium

Minimum Number of Pushes to Type Word II

CountingGreedyHash Table+2

Acceptance: 83.2%

#3020Medium

Find the Maximum Number of Elements in Subset

ArrayEnumerationHash Table

Acceptance: 42.2%

#3021Medium

Alice and Bob Playing Flower Game

Math

Acceptance: 60.2%

#3023Medium

Find Pattern in Infinite Stream I

ArrayHash FunctionRolling Hash+2

Acceptance: 57.5%

#3025Medium

Find the Number of Ways to Place People I

ArrayEnumerationGeometry+2

Acceptance: 64.0%

#3026Medium

Maximum Good Subarray Sum

ArrayHash TablePrefix Sum

Acceptance: 22.1%

#3029Medium

Minimum Time to Revert Word to Initial State I

Hash FunctionRolling HashString+1

Acceptance: 42.4%

#3030Medium

Find the Grid of Region Average

ArrayMatrix

Acceptance: 43.0%

#3034Medium

Number of Subarrays That Match a Pattern I

ArrayHash FunctionRolling Hash+1

Acceptance: 67.9%

#3035Medium

Maximum Palindromes After Operations

ArrayCountingGreedy+3

Acceptance: 47.2%

#3039Medium

Apply Operations to Make String Empty

ArrayCountingHash Table+1

Acceptance: 57.5%

#3040Medium

Maximum Number of Operations With the Same Score II

ArrayDynamic ProgrammingMemoization

Acceptance: 34.1%

1 2 331 32 3341 42 43

Page 32 of 43

Master DSA with Step-by-Step Solutions

Each solution article on FleetCode breaks down the problem into multiple approaches, from brute force to optimal, with detailed explanations and code in Python, Java, C++ and more. Understanding why an approach works - not just copying code - is what separates candidates who clear interviews from those who don't.

How to Use These Solutions

Try the problem first: Spend at least 20 minutes before reading the solution
Read all approaches: Start from brute force to understand the problem fully, then study the optimized solution
Understand the complexity: Pay attention to time and space analysis for each approach
Code it yourself: After understanding the approach, close the solution and implement from memory
Revisit after a week: Spaced repetition helps retain problem-solving patterns