Skip List: Design and Applications
6 min read A skip list is a probabilistic data structure that provides O(log n) average time for search, insertion, and deletion — […] Read article
Data Structures
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Data Structures
Deep dive into essential data structures that every software engineer must master. From basic arrays and linked lists to advanced structures like tries and segment trees, this category prepares you for any data structure question.
Core Data Structures:
Linear: Arrays, linked lists, stacks, queues
Hierarchical: Binary trees, BSTs, heaps, tries
Hash-based: Hash maps, hash sets, bloom filters
Advanced: Graphs, disjoint sets, segment trees
Key Skills:
Choosing the right data structure for the problem
Understanding time/space tradeoffs
Implementing from scratch in interviews
Optimizing operations (insert, delete, search)
Companies: Every major tech company tests data structures. Particularly important at Amazon, Google, and Microsoft.
Data Structures
Merkle Tree: Design and Applications
6 min read A Merkle tree is a hash tree where every leaf node contains the hash of a data block, and every Read article
Data Structures
Bloom Filter: Design and Applications
6 min read A Bloom filter is a space-efficient probabilistic data structure that answers membership queries: “Is this element in the set?” It Read article
Algorithms, Coding Interview Questions, Data Structures
Matrix Traversal Interview Patterns
7 min read Grid Traversal Fundamentals Most matrix problems involve: (1) BFS from one or multiple source cells, (2) DFS to explore connected Read article
Algorithms, Coding Interview Questions, Data Structures
Ordered Map (TreeMap / SortedList) Interview Patterns
6 min read When to Use an Ordered Map (Sorted Dict / TreeMap) An ordered map maintains keys in sorted order with O(log Read article
Algorithms, Coding Interview Questions, Data Structures, Heap
Advanced Heap Interview Patterns
10 min read Advanced Heap Interview Patterns Heaps appear in a surprising number of interview problems beyond the simple “find the Kth largest Read article
Algorithms, Coding Interview Questions, Data Structures
Sorting Algorithm Interview Patterns
10 min read Sorting problems appear constantly in interviews – not just “implement merge sort” but as tools to simplify harder problems. Master Read article
Algorithms, Coding Interview Questions, Data Structures
Range Query Interview Patterns
10 min read Range query problems appear frequently in competitive programming and technical interviews. Knowing which data structure to reach for – and Read article
Data Structures
Implement a Rate Limiter: Token Bucket, Leaky Bucket, Sliding Window
8 min read Implement a Rate Limiter: Token Bucket, Leaky Bucket, Sliding Window Rate limiting is one of the most-asked system-design topics in Read article
Data Structures, System Design
Detect Phone Numbers Missing a Country Code: Heuristics and libphonenumber
5 min read Parse Phone Numbers Without a Country Code: Heuristic Detection “Given a list of phone numbers in mixed formats, identify which Read article
Data Structures
Detect a Cycle in a Linked List: Floyd Algorithm and Cycle Entry
6 min read Detect a Cycle in a Linked List: Floyd’s Algorithm and Cycle Entry Point Detecting a cycle in a linked list Read article
Arrays, Data Structures
Missing or Duplicate Number in an Array: XOR, Floyd, Cyclic Sort
6 min read Missing or Duplicate Number in an Array: XOR, Sum, Cyclic Sort, and Floyd’s Algorithm Finding the missing number or the Read article
Arrays, Data Structures, Math Problems
Probability Distribution Functions: PMF, PDF, CDF, and Common Distributions
5 min read Probability Distribution Functions: PMF, PDF, CDF, and the Common Distributions Understanding probability distribution functions is foundational for quant trading interviews, Read article
Bit Manipulation, Data Structures
Find the Depth of a Binary Tree: Recursive, BFS, Iterative DFS
6 min read Find the Depth (Height) of a Binary Tree: Recursive, Iterative BFS, and Iterative DFS Finding the depth (also called height Read article
Algorithms, Data Structures
Check If a Linked List Is a Palindrome: Stack, Reverse-Half, Recursive
6 min read Check If a Linked List Is a Palindrome: Stack, Reverse-Half, and Recursive Approaches Palindrome linked list (LeetCode #234) is a Read article