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DSA Question Tracker & Breakdowns

240 problems tagged Array with full breakdowns.

433problems
32companies
39topics
3languages each

Companies

Amazon80Microsoft79Google76Meta76Apple73Uber64Walmart54Atlassian52Bloomberg51Oracle49Salesforce49Goldman Sachs39TikTok34Netflix32Databricks25LinkedIn24Visa23Anduril21Rippling21Snowflake20Adobe16NVIDIA16DE Shaw14JPMorgan14OpenAI14Pinterest14Capital One12Roblox11Airbnb9Flipkart9Anthropic4Ripple4

Topics

Array 240Hash Table 113String 112Depth-First Search 73Sorting 66Dynamic Programming 65Breadth-First Search 56Math 49Design 46Binary Search 44Greedy 43Tree 41Two Pointers 39Heap 35Stack 32Graph 28Matrix 28Sliding Window 26Binary Tree 23Backtracking 22Bit Manipulation 20Prefix Sum 20Simulation 20Union Find 19Linked List 18Queue 13Trie 12Counting 10Recursion 10Divide and Conquer 9Monotonic Stack 9Ordered Set 9Topological Sort 9Data Stream 8Database 6Enumeration 6Binary Search Tree 5Doubly-Linked List 5Geometry 5
Array✕Clear all
1.Two Sum
ArrayHash Table
Easy+10▶ Mock
56.Merge Intervals
ArraySorting
Medium+14▶ Mock
121.Best Time to Buy and Sell Stock
ArrayDynamic Programming
Easy+10▶ Mock
15.3Sum
ArrayTwo PointersSorting
Medium+5▶ Mock
11.Container With Most Water
ArrayTwo PointersGreedy
Medium+6▶ Mock
42.Trapping Rain Water
ArrayTwo PointersStack
Hard+6▶ Mock
4.Median of Two Sorted Arrays
ArrayBinary SearchDivide and Conquer
Hard+5▶ Mock
347.Top K Frequent Elements
ArrayHash TableHeap
Medium+6▶ Mock
128.Longest Consecutive Sequence
ArrayHash TableUnion Find
Medium+3▶ Mock
198.House Robber
Dynamic ProgrammingArray
Medium+1▶ Mock
560.Subarray Sum Equals K
ArrayHash TablePrefix Sum
Medium+2▶ Mock
33.Search in Rotated Sorted Array
ArrayBinary Search
Medium+5▶ Mock
53.Maximum Subarray
ArrayDynamic ProgrammingDivide and Conquer
Medium+7▶ Mock
238.Product of Array Except Self
ArrayPrefix Sum
Medium+5▶ Mock
739.Daily Temperatures
StackArray
Medium+4▶ Mock
253.Meeting Rooms II
ArrayHeapSorting
Medium+6▶ Mock
134.Gas Station
ArrayGreedy
Medium+5▶ Mock
152.Maximum Product Subarray
ArrayDynamic Programming
Medium+4▶ Mock
283.Move Zeroes
ArrayTwo Pointers
Easy▶ Mock
45.Jump Game II
ArrayDynamic ProgrammingGreedy
Medium▶ Mock
34.Find First and Last Position of Element in Sorted Array
ArrayBinary Search
Medium+1▶ Mock
1146.Snapshot Array
ArrayHash TableBinary Search
Medium▶ Mock
75.Sort Colors
ArrayTwo PointersSorting
Medium▶ Mock
14.Longest Common Prefix
ArrayStringTrie
Easy+1▶ Mock
26.Remove Duplicates from Sorted Array
ArrayTwo Pointers
Easy+1▶ Mock
79.Word Search
ArrayStringBacktracking
Medium+1▶ Mock
189.Rotate Array
ArrayMathTwo Pointers
Medium+1▶ Mock
88.Merge Sorted Array
ArrayTwo PointersSorting
Easy+1▶ Mock
54.Spiral Matrix
ArrayMatrixSimulation
Medium+2▶ Mock
78.Subsets
ArrayBacktrackingBit Manipulation
Medium▶ Mock
215.Kth Largest Element in an Array
ArrayDivide and ConquerSorting
Medium▶ Mock
122.Best Time to Buy and Sell Stock II
ArrayDynamic ProgrammingGreedy
Medium▶ Mock
399.Evaluate Division
ArrayStringDepth-First Search
Medium▶ Mock
380.Insert Delete GetRandom O(1)
ArrayHash TableMath
Medium▶ Mock
721.Accounts Merge
ArrayHash TableString
Medium▶ Mock
2502.Design Memory Allocator
ArrayHash TableDesign
Medium+1▶ Mock
239.Sliding Window Maximum
ArrayQueueSliding Window
Hard+2▶ Mock
1929.Concatenation of Array
ArraySimulation
Easy▶ Mock
904.Fruit Into Baskets
ArrayHash TableSliding Window
Medium▶ Mock
167.Two Sum II - Input Array Is Sorted
ArrayTwo PointersBinary Search
Medium▶ Mock
977.Squares of a Sorted Array
ArrayTwo PointersSorting
Easy▶ Mock
31.Next Permutation
ArrayTwo Pointers
Medium▶ Mock
875.Koko Eating Bananas
ArrayBinary Search
Medium▶ Mock
735.Asteroid Collision
ArrayStackSimulation
Medium+1▶ Mock
169.Majority Element
ArrayHash TableDivide and Conquer
Easy▶ Mock
362.Design Hit Counter
ArrayBinary SearchDesign
Medium▶ Mock
410.Split Array Largest Sum
ArrayBinary SearchDynamic Programming
Hard▶ Mock
41.First Missing Positive
ArrayHash Table
Hard▶ Mock
2639.Find the Width of Columns of a Grid
ArrayMatrix
Easy▶ Mock
2408.Design SQL
ArrayHash TableString
Medium▶ Mock
2035.Partition Array Into Two Arrays to Minimize Sum Difference
ArrayBinary SearchDynamic Programming
Hard▶ Mock
2503.Maximum Number of Points from Grid Queries
ArrayTwo PointersBreadth-First Search
Hard▶ Mock
1962.Remove Stones to Minimize the Total
ArrayGreedyHeap
Medium▶ Mock
3471.Find the Largest Almost Missing Integer
ArrayHash Table
Easy▶ Mock
40.Combination Sum II
ArrayBacktracking
Medium▶ Mock
1091.Shortest Path in a Binary Matrix
ArrayBreadth-First SearchMatrix
Medium▶ Mock
1429.First Unique Number
ArrayHash TableDesign
Medium▶ Mock
704.Binary Search
ArrayBinary Search
Easy▶ Mock
300.Longest Increasing Subsequence
ArrayBinary SearchDynamic Programming
Medium▶ Mock
1049.Last Stone Weight II
ArrayDynamic ProgrammingKnapsack
Medium▶ Mock
503.Next Greater Element II
ArrayStackMonotonic Stack
Medium▶ Mock
303.Range Sum Query - Immutable
ArrayDesignPrefix Sum
Easy▶ Mock
2402.Meeting Rooms III
ArrayHash TableSorting
Hard▶ Mock
48.Rotate Image
ArrayMathMatrix
Medium▶ Mock
1046.Last Stone Weight
ArrayHeap
Easy▶ Mock
219.Contains Duplicate II
ArrayHash TableSliding Window
Easy▶ Mock
1335.Minimum Difficulty of a Job Schedule
ArrayDynamic Programming
Hard▶ Mock
68.Text Justification
ArrayStringSimulation
Hard▶ Mock
217.Contains Duplicate
ArrayHash TableSorting
Easy▶ Mock
39.Combination Sum
ArrayBacktracking
Medium▶ Mock
3484.Design Spreadsheet
ArrayHash TableString
Medium▶ Mock
631.Design Excel Sum Formula
ArrayHash TableString
Hard▶ Mock
900.RLE Iterator
ArrayDesignCounting
Medium▶ Mock
3043.Find the Length of the Longest Common Prefix
ArrayHash TableString
Medium▶ Mock
16.3Sum Closest
ArrayTwo PointersSorting
Medium▶ Mock
18.4Sum
ArrayTwo PointersSorting
Medium▶ Mock
870.Advantage Shuffle
ArrayTwo PointersGreedy
Medium▶ Mock
526.Beautiful Arrangement
ArrayDynamic ProgrammingBacktracking
Medium▶ Mock
1966.Binary Searchable Numbers in an Unsorted Array
ArrayBinary SearchStack
Medium▶ Mock
815.Bus Routes
ArrayHash TableBreadth-First Search
Hard▶ Mock
605.Can Place Flowers
ArrayGreedy
Easy▶ Mock
1011.Capacity To Ship Packages Within D Days
ArrayBinary Search
Medium▶ Mock
1752.Check if Array Is Sorted and Rotated
Array
Easy▶ Mock
1386.Cinema Seat Allocation
ArrayHash TableGreedy
Medium▶ Mock
427.Construct Quad Tree
ArrayDivide and ConquerTree
Medium▶ Mock
3875.Construct Uniform Parity Array I
ArrayMath
Easy▶ Mock
220.Contains Duplicate III
ArraySliding WindowSorting
Hard▶ Mock
3067.Count Pairs of Connectable Servers in a Weighted Tree Network
ArrayTreeDepth-First Search
Medium▶ Mock
2444.Count Subarrays With Fixed Bounds
ArrayQueueSliding Window
Hard▶ Mock
2954.Count the Number of Infection Sequences
ArrayMathCombinatorics
Hard▶ Mock
2559.Count Vowel Strings in Ranges
ArrayStringPrefix Sum
Medium▶ Mock
740.Delete and Earn
ArrayHash TableDynamic Programming
Medium▶ Mock
2353.Design a Food Rating System
ArrayHash TableString
Medium▶ Mock
353.Design Snake Game
ArrayHash TableDesign
Medium▶ Mock
348.Design Tic-Tac-Toe
ArrayHash TableDesign
Medium▶ Mock
271.Encode and Decode Strings
ArrayStringDesign
Medium▶ Mock
636.Exclusive Time of Functions
ArrayStack
Medium▶ Mock
1475.Final Prices With a Special Discount in a Shop
ArrayStackMonotonic Stack
Easy▶ Mock
55.Jump Game
ArrayDynamic ProgrammingGreedy
Medium▶ Mock
153.Find Minimum in Rotated Sorted Array
ArrayBinary Search
Medium▶ Mock
162.Find Peak Element
ArrayBinary Search
Medium▶ Mock
57.Insert Interval
Array
Medium▶ Mock
986.Interval List Intersections
ArrayTwo PointersSweep Line
Medium▶ Mock
84.Largest Rectangle in Histogram
ArrayStackMonotonic Stack
Hard▶ Mock
289.Game of Life
ArrayMatrixSimulation
Medium▶ Mock
287.Find the Duplicate Number
ArrayTwo PointersBinary Search
Medium▶ Mock
179.Largest Number
ArrayStringGreedy
Medium▶ Mock
213.House Robber II
ArrayDynamic Programming
Medium▶ Mock
1048.Longest String Chain
ArrayHash TableTwo Pointers
Medium▶ Mock
845.Longest Mountain in Array
ArrayTwo PointersDynamic Programming
Medium▶ Mock
658.Find K Closest Elements
ArrayTwo PointersBinary Search
Medium▶ Mock
2933.High-Access Employees
ArrayHash TableString
Medium▶ Mock
609.Find Duplicate File in System
ArrayHash TableString
Medium▶ Mock
2812.Find the Safest Path in a Grid
ArrayBinary SearchBreadth-First Search
Medium▶ Mock
1438.Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit
ArrayQueueSliding Window
Medium▶ Mock
2373.Largest Local Values in a Matrix
ArrayMatrix
Easy▶ Mock
1004.Max Consecutive Ones III
ArrayBinary SearchSliding Window
Medium▶ Mock
643.Maximum Average Subarray I
ArraySliding Window
Easy▶ Mock
1200.Minimum Absolute Difference
ArraySorting
Easy▶ Mock
983.Minimum Cost For Tickets
ArrayDynamic Programming
Medium▶ Mock
628.Maximum Product of Three Numbers
ArrayMathSorting
Easy▶ Mock
3914.Minimum Operations to Make Array Non Decreasing
ArrayGreedy
Medium▶ Mock
209.Minimum Size Subarray Sum
ArrayBinary SearchSliding Window
Medium▶ Mock
2461.Maximum Sum of Distinct Subarrays With Length K
ArrayHash TableSliding Window
Medium▶ Mock
849.Maximize Distance to Closest Person
Array
Medium▶ Mock
46.Permutations
ArrayBacktracking
Medium▶ Mock
66.Plus One
ArrayMath
Easy▶ Mock
2551.Put Marbles in Bags
ArrayGreedySorting
Hard▶ Mock
1366.Rank Teams by Votes
ArrayHash TableString
Medium▶ Mock
2561.Rearranging Fruits
ArrayHash TableGreedy
Hard▶ Mock
27.Remove Element
ArrayTwo Pointers
Easy▶ Mock
51.N-Queens
ArrayBacktrackingAlgorithm X
Hard▶ Mock
857.Minimum Cost to Hire K Workers
ArrayGreedySorting
Hard▶ Mock
1928.Minimum Cost to Reach Destination in Time
ArrayDynamic ProgrammingGraph
Hard▶ Mock
871.Minimum Number of Refueling Stops
ArrayDynamic ProgrammingGreedy
Hard▶ Mock
827.Making A Large Island
ArrayDepth-First SearchBreadth-First Search
Hard▶ Mock
3035.Maximum Palindromes After Operations
ArrayHash TableString
Medium▶ Mock
3893.Maximum Team Size with Overlapping Intervals
ArraySortingUnion Find
Medium▶ Mock
3634.Minimum Removals to Balance Array
ArrayBinary SearchSliding Window
Medium▶ Mock
2366.Minimum Replacements to Sort the Array
ArrayMathGreedy
Hard▶ Mock
3413.Maximum Coins From K Consecutive Bags
ArrayBinary SearchGreedy
Medium▶ Mock
3953.Maximum Score with Co-Prime Element
ArrayHash TableMath
Hard▶ Mock
3387.Maximize Amount After Two Days of Conversions
ArrayStringDepth-First Search
Medium▶ Mock
2251.Number of Flowers in Full Bloom
ArrayHash TableBinary Search
Hard▶ Mock
305.Number of Islands II
ArrayHash TableUnion Find
Hard▶ Mock
3649.Number of Perfect Pairs
ArrayMathTwo Pointers
Medium▶ Mock
1944.Number of Visible People in a Queue
ArrayStackMonotonic Stack
Hard▶ Mock
1639.Number of Ways to Form a Target String Given a Dictionary
ArrayStringDynamic Programming
Hard▶ Mock
465.Optimal Account Balancing
ArrayDynamic ProgrammingBacktracking
Hard▶ Mock
74.Search a 2D Matrix
ArrayBinary SearchMatrix
Medium▶ Mock
35.Search Insert Position
ArrayBinary Search
Easy▶ Mock
73.Set Matrix Zeroes
ArrayHash TableMatrix
Medium▶ Mock
136.Single Number
ArrayBit Manipulation
Easy▶ Mock
912.Sort an Array
ArrayDivide and ConquerSorting
Medium▶ Mock
36.Valid Sudoku
ArrayHash TableMatrix
Medium▶ Mock
228.Summary Ranges
Array
Easy▶ Mock
645.Set Mismatch
ArrayHash TableBit Manipulation
Easy▶ Mock
3718.Smallest Missing Multiple of K
ArrayHash Table
Easy▶ Mock
713.Subarray Product Less Than K
ArrayBinary SearchSliding Window
Medium▶ Mock
692.Top K Frequent Words
ArrayHash TableString
Medium▶ Mock
384.Shuffle an Array
ArrayMathDesign
Medium▶ Mock
1010.Pairs of Songs With Total Durations Divisible by 60
ArrayHash TableCounting
Medium▶ Mock
737.Sentence Similarity II
ArrayHash TableString
Medium▶ Mock
1101.The Earliest Moment When Everyone Become Friends
ArrayUnion FindSorting
Medium▶ Mock
2039.The Time When the Network Becomes Idle
ArrayBreadth-First SearchGraph
Medium▶ Mock
1970.Last Day Where You Can Still Cross
ArrayBinary SearchDepth-First Search
Hard▶ Mock
1428.Leftmost Column with at Least a One
ArrayBinary SearchMatrix
Medium▶ Mock
2213.Longest Substring of One Repeating Character
ArrayStringSegment Tree
Hard▶ Mock
2948.Make Lexicographically Smallest Array by Swapping Elements
ArrayUnion FindSorting
Medium▶ Mock
332.Reconstruct Itinerary
ArrayStringDepth-First Search
Hard▶ Mock
354.Russian Doll Envelopes
ArrayBinary SearchDynamic Programming
Hard▶ Mock
1293.Shortest Path in a Grid with Obstacles Elimination
ArrayBreadth-First SearchMatrix
Hard▶ Mock
2718.Sum of Matrix After Queries
ArrayHash Table
Medium▶ Mock
1258.Synonymous Sentences
ArrayHash TableString
Medium▶ Mock
980.Unique Paths III
ArrayBacktrackingBit Manipulation
Hard▶ Mock
140.Word Break II
ArrayHash TableString
Hard▶ Mock
Missing Number
ArrayHash TableMath
Easy▶ Mock
Word Search II
ArrayStringBacktracking
Hard+1▶ Mock
64.Minimum Path Sum
ArrayDynamic ProgrammingMatrix
Medium▶ Mock
118.Pascal's Triangle
ArrayDynamic Programming
Easy▶ Mock
149.Max Points on a Line
ArrayHash TableMath
Hard▶ Mock
240.Search a 2D Matrix II
ArrayBinary SearchDivide and Conquer
Medium▶ Mock
243.Shortest Word Distance
ArrayString
Easy▶ Mock
244.Shortest Word Distance II
ArrayHash TableTwo Pointers
Medium▶ Mock
381.Insert Delete GetRandom O(1) - Duplicates allowed
ArrayHash TableMath
Hard▶ Mock
475.Heaters
ArrayTwo PointersBinary Search
Medium▶ Mock
494.Target Sum
ArrayDynamic ProgrammingBacktracking
Medium▶ Mock
496.Next Greater Element I
ArrayHash TableStack
Easy▶ Mock
528.Random Pick with Weight
ArrayMathBinary Search
Medium▶ Mock
622.Design Circular Queue
ArrayLinked ListDesign
Medium▶ Mock
706.Design HashMap
ArrayHash TableLinked List
Easy▶ Mock
723.Candy Crush
ArrayTwo PointersMatrix
Medium▶ Mock
749.Contain Virus
ArrayDepth-First SearchBreadth-First Search
Hard▶ Mock
773.Sliding Puzzle
ArrayDynamic ProgrammingBacktracking
Hard▶ Mock
851.Loud and Rich
ArrayDepth-First SearchGraph
Medium▶ Mock
853.Car Fleet
ArrayStackSorting
Medium▶ Mock
928.Minimize Malware Spread II
ArrayHash TableDepth-First Search
Hard▶ Mock
973.K Closest Points to Origin
ArrayMathDivide and Conquer
Medium▶ Mock
974.Subarray Sums Divisible by K
ArrayHash TablePrefix Sum
Medium▶ Mock
1029.Two City Scheduling
ArrayGreedySorting
Medium▶ Mock
1043.Partition Array for Maximum Sum
ArrayDynamic Programming
Medium▶ Mock
1086.High Five
ArrayHash TableSorting
Easy▶ Mock
1125.Smallest Sufficient Team
ArrayDynamic ProgrammingBit Manipulation
Hard▶ Mock
1202.Smallest String With Swaps
ArrayHash TableString
Medium▶ Mock
1235.Maximum Profit in Job Scheduling
ArrayBinary SearchDynamic Programming
Hard▶ Mock
1248.Count Number of Nice Subarrays
ArrayHash TableMath
Medium▶ Mock
1298.Maximum Candies You Can Get from Boxes
ArrayBreadth-First SearchGraph
Hard▶ Mock
1352.Product of the Last K Numbers
ArrayMathDesign
Medium▶ Mock
1353.Maximum Number of Events That Can Be Attended
ArrayGreedySorting
Medium▶ Mock
1434.Number of Ways to Wear Different Hats to Each Other
ArrayDynamic ProgrammingBit Manipulation
Hard▶ Mock
1482.Minimum Number of Days to Make m Bouquets
ArrayBinary Search
Medium▶ Mock
1535.Find the Winner of an Array Game
ArraySimulation
Medium▶ Mock
1564.Put Boxes Into the Warehouse I
ArrayGreedySorting
Medium▶ Mock
1610.Maximum Number of Visible Points
ArrayMathGeometry
Hard▶ Mock
1642.Furthest Building You Can Reach
ArrayGreedyHeap
Medium▶ Mock
1648.Sell Diminishing-Valued Colored Balls
ArrayMathBinary Search
Medium▶ Mock
1710.Maximum Units on a Truck
ArrayGreedySorting
Easy▶ Mock
1751.Maximum Number of Events That Can Be Attended II
ArrayBinary SearchDynamic Programming
Hard▶ Mock
1762.Buildings With an Ocean View
ArrayStackMonotonic Stack
Medium▶ Mock
1823.Find the Winner of the Circular Game
ArrayMathRecursion
Medium▶ Mock
1828.Queries on Number of Points Inside a Circle
ArrayMathGeometry
Medium▶ Mock
1834.Single-Threaded CPU
ArraySortingHeap
Medium▶ Mock
2043.Simple Bank System
ArrayHash TableDesign
Medium▶ Mock
2050.Parallel Courses III
ArrayDynamic ProgrammingGraph
Hard▶ Mock
2101.Detonate the Maximum Bombs
ArrayMathDepth-First Search
Medium▶ Mock
2171.Removing Minimum Number of Magic Beans
ArrayGreedySorting
Medium▶ Mock
2237.Count Positions on Street With Required Brightness
ArrayPrefix Sum
Medium▶ Mock
2303.Calculate Amount Paid in Taxes
ArraySimulation
Easy▶ Mock
2439.Minimize Maximum of Array
ArrayBinary SearchDynamic Programming
Medium▶ Mock
2491.Divide Players Into Teams of Equal Skill
ArrayHash TableTwo Pointers
Medium▶ Mock
2672.Number of Adjacent Elements With the Same Color
Array
Medium▶ Mock
2680.Maximum OR
ArrayGreedyBit Manipulation
Medium▶ Mock
2895.Minimum Processing Time
ArrayGreedySorting
Medium▶ Mock
2964.Number of Divisible Triplet Sums
ArrayHash Table
Medium▶ Mock
3076.Shortest Uncommon Substring in an Array
ArrayHash TableString
Medium▶ Mock
3078.Match Alphanumerical Pattern in Matrix I
ArrayHash TableString
Medium▶ Mock
3092.Most Frequent IDs
ArrayHash TableHeap
Medium▶ Mock
3161.Block Placement Queries
ArrayBinary SearchBinary Indexed Tree
Hard▶ Mock
3208.Alternating Groups II
ArraySliding Window
Medium▶ Mock
3919.Minimum Cost to Move Between Indices
ArrayPrefix Sum
Medium▶ Mock

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