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DSA Question Tracker & Breakdowns

113 problems tagged Hash Table 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
Hash Table✕Clear all
1.Two Sum
ArrayHash Table
Easy+10▶ Mock
3.Longest Substring Without Repeating Characters
Hash TableStringSliding Window
Medium+13▶ Mock
49.Group Anagrams
Hash TableStringSorting
Medium+9▶ Mock
347.Top K Frequent Elements
ArrayHash TableHeap
Medium+6▶ Mock
128.Longest Consecutive Sequence
ArrayHash TableUnion Find
Medium+3▶ Mock
560.Subarray Sum Equals K
ArrayHash TablePrefix Sum
Medium+2▶ Mock
146.LRU Cache
Hash TableLinked ListDesign
Medium+9▶ Mock
139.Word Break
Dynamic ProgrammingHash TableTrie
Medium+5▶ Mock
438.Find All Anagrams in a String
Hash TableStringSliding Window
Medium+2▶ Mock
133.Clone Graph
Depth-First SearchBreadth-First SearchGraph
Medium+1▶ Mock
621.Task Scheduler
GreedyHeapHash Table
Medium+2▶ Mock
460.LFU Cache
Hash TableLinked ListDesign
Hard+1▶ Mock
1146.Snapshot Array
ArrayHash TableBinary Search
Medium▶ Mock
567.Permutation in String
Hash TableTwo PointersString
Medium▶ Mock
981.Time Based Key-Value Store
Hash TableStringBinary Search
Medium+1▶ Mock
76.Minimum Window Substring
Hash TableStringSliding Window
Hard▶ Mock
13.Roman to Integer
Hash TableMathString
Easy+1▶ Mock
17.Letter Combinations of a Phone Number
Hash TableStringBacktracking
Medium+1▶ Mock
12.Integer to Roman
Hash TableMathString
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
904.Fruit Into Baskets
ArrayHash TableSliding Window
Medium▶ Mock
169.Majority Element
ArrayHash TableDivide and Conquer
Easy▶ Mock
41.First Missing Positive
ArrayHash Table
Hard▶ Mock
138.Copy List with Random Pointer
Hash TableLinked List
Medium+1▶ Mock
2408.Design SQL
ArrayHash TableString
Medium▶ Mock
3471.Find the Largest Almost Missing Integer
ArrayHash Table
Easy▶ Mock
1429.First Unique Number
ArrayHash TableDesign
Medium▶ Mock
424.Longest Repeating Character Replacement
Hash TableStringSliding Window
Medium▶ Mock
1797.Design Authentication Manager
Hash TableLinked ListDesign
Medium▶ Mock
2402.Meeting Rooms III
ArrayHash TableSorting
Hard▶ Mock
127.Word Ladder
Hash TableStringBreadth-First Search
Hard▶ Mock
219.Contains Duplicate II
ArrayHash TableSliding Window
Easy▶ Mock
359.Design Logger Rate Limiter
Hash TableDesignData Stream
Easy▶ Mock
217.Contains Duplicate
ArrayHash TableSorting
Easy▶ Mock
2034.Stock Price Fluctuation
Hash TableDesignHeap
Medium▶ Mock
3484.Design Spreadsheet
ArrayHash TableString
Medium▶ Mock
631.Design Excel Sum Formula
ArrayHash TableString
Hard▶ Mock
3043.Find the Length of the Longest Common Prefix
ArrayHash TableString
Medium▶ Mock
2062.Count Vowel Substrings of a String
Hash TableString
Easy▶ Mock
432.All O'one Data Structure
Hash TableLinked ListDesign
Hard▶ Mock
1138.Alphabet Board Path
Hash TableString
Medium▶ Mock
2385.Amount of Time for Binary Tree to Be Infected
Hash TableTreeDepth-First Search
Medium▶ Mock
314.Binary Tree Vertical Order Traversal
Hash TableTreeDepth-First Search
Medium▶ Mock
815.Bus Routes
ArrayHash TableBreadth-First Search
Hard▶ Mock
1386.Cinema Seat Allocation
ArrayHash TableGreedy
Medium▶ Mock
2791.Count Paths That Can Form a Palindrome in a Tree
Hash TableBit ManipulationTree
Hard▶ Mock
740.Delete and Earn
ArrayHash TableDynamic Programming
Medium▶ Mock
2353.Design a Food Rating System
ArrayHash TableString
Medium▶ Mock
588.Design In-Memory File System
Hash TableStringDesign
Hard▶ Mock
3829.Design Ride Sharing System
Hash TableDesignQueue
Medium▶ Mock
353.Design Snake Game
ArrayHash TableDesign
Medium▶ Mock
3408.Design Task Manager
Hash TableDesignHeap
Medium▶ Mock
348.Design Tic-Tac-Toe
ArrayHash TableDesign
Medium▶ Mock
1396.Design Underground System
Hash TableStringDesign
Medium▶ Mock
141.Linked List Cycle
Hash TableLinked ListTwo Pointers
Easy▶ Mock
1048.Longest String Chain
ArrayHash TableTwo Pointers
Medium▶ Mock
2933.High-Access Employees
ArrayHash TableString
Medium▶ Mock
609.Find Duplicate File in System
ArrayHash TableString
Medium▶ Mock
2461.Maximum Sum of Distinct Subarrays With Length K
ArrayHash TableSliding Window
Medium▶ Mock
3090.Maximum Length Substring With Two Occurrences
Hash TableStringSliding Window
Easy▶ Mock
1366.Rank Teams by Votes
ArrayHash TableString
Medium▶ Mock
2561.Rearranging Fruits
ArrayHash TableGreedy
Hard▶ Mock
767.Reorganize String
Hash TableStringGreedy
Medium▶ Mock
3035.Maximum Palindromes After Operations
ArrayHash TableString
Medium▶ Mock
3953.Maximum Score with Co-Prime Element
ArrayHash TableMath
Hard▶ Mock
2251.Number of Flowers in Full Bloom
ArrayHash TableBinary Search
Hard▶ Mock
305.Number of Islands II
ArrayHash TableUnion Find
Hard▶ Mock
1915.Number of Wonderful Substrings
Hash TableStringBit Manipulation
Medium▶ Mock
73.Set Matrix Zeroes
ArrayHash TableMatrix
Medium▶ Mock
36.Valid Sudoku
ArrayHash TableMatrix
Medium▶ Mock
645.Set Mismatch
ArrayHash TableBit Manipulation
Easy▶ Mock
3718.Smallest Missing Multiple of K
ArrayHash Table
Easy▶ Mock
692.Top K Frequent Words
ArrayHash TableString
Medium▶ Mock
1010.Pairs of Songs With Total Durations Divisible by 60
ArrayHash TableCounting
Medium▶ Mock
737.Sentence Similarity II
ArrayHash TableString
Medium▶ Mock
1650.Lowest Common Ancestor of a Binary Tree III
Hash TableTwo PointersTree
Medium▶ Mock
1676.Lowest Common Ancestor of a Binary Tree IV
Hash TableTreeDepth-First Search
Medium▶ Mock
2718.Sum of Matrix After Queries
ArrayHash Table
Medium▶ Mock
1258.Synonymous Sentences
ArrayHash TableString
Medium▶ Mock
2434.Using a Robot to Print the Lexicographically Smallest String
Hash TableStringStack
Medium▶ Mock
987.Vertical Order Traversal of a Binary Tree
Hash TableTreeDepth-First Search
Hard▶ Mock
140.Word Break II
ArrayHash TableString
Hard▶ Mock
Valid Anagram
Hash TableStringSorting
Easy▶ Mock
Missing Number
ArrayHash TableMath
Easy▶ Mock
Happy Number
Hash TableMathTwo Pointers
Easy+1▶ Mock
149.Max Points on a Line
ArrayHash TableMath
Hard▶ Mock
166.Fraction to Recurring Decimal
Hash TableMathString
Medium▶ Mock
205.Isomorphic Strings
Hash TableString
Easy▶ Mock
244.Shortest Word Distance II
ArrayHash TableTwo Pointers
Medium▶ Mock
340.Longest Substring with At Most K Distinct Characters
Hash TableStringSliding Window
Medium▶ Mock
381.Insert Delete GetRandom O(1) - Duplicates allowed
ArrayHash TableMath
Hard▶ Mock
383.Ransom Note
Hash TableStringCounting
Easy▶ Mock
387.First Unique Character in a String
Hash TableStringQueue
Easy▶ Mock
496.Next Greater Element I
ArrayHash TableStack
Easy▶ Mock
694.Number of Distinct Islands
Hash TableDepth-First SearchBreadth-First Search
Medium▶ Mock
706.Design HashMap
ArrayHash TableLinked List
Easy▶ Mock
928.Minimize Malware Spread II
ArrayHash TableDepth-First Search
Hard▶ Mock
974.Subarray Sums Divisible by K
ArrayHash TablePrefix Sum
Medium▶ Mock
1086.High Five
ArrayHash TableSorting
Easy▶ Mock
1202.Smallest String With Swaps
ArrayHash TableString
Medium▶ Mock
1244.Design A Leaderboard
Hash TableDesignSorting
Medium▶ Mock
1248.Count Number of Nice Subarrays
ArrayHash TableMath
Medium▶ Mock
1297.Maximum Number of Occurrences of a Substring
Hash TableStringSliding Window
Medium▶ Mock
1347.Minimum Number of Steps to Make Two Strings Anagram
Hash TableStringCounting
Medium▶ Mock
1600.Throne Inheritance
Hash TableTreeDepth-First Search
Medium▶ Mock
2043.Simple Bank System
ArrayHash TableDesign
Medium▶ Mock
2491.Divide Players Into Teams of Equal Skill
ArrayHash TableTwo Pointers
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

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