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Deep dives into algorithms, system design and AI

26 posts

Language: 中文 EN

January 13, 2026 EN

Graph Data Structure - Complete Guide with DFS & BFS Traversal

Master graph data structures with interactive visualizations. Learn adjacency list vs matrix representations, implement DFS and BFS traversals in Java, Python, JavaScript. Complete guide for coding interviews at FAANG and top tech companies.

#algorithm #graph #dfs #bfs #data-structure #visualization #interview #leetcode

January 13, 2026 EN

Topological Sort: Complete Interview Guide with DFS and Kahn's Algorithm

Master topological sort with interactive visualizations. Learn both DFS and Kahn's algorithm approaches, solve LeetCode problems, and ace your FAANG interviews.

#algorithm #graph #topological-sort #dfs #bfs #interview #leetcode #visualization

January 12, 2026 EN

Java Data Structures Quick Reference for LeetCode - Complete Cheat Sheet

Master essential Java data structures for coding interviews with this comprehensive guide covering Queue, Stack, List, Set, Map, Heap, String, and Array utilities. Includes method signatures, time complexity, and LeetCode patterns from 11-year FAANG veteran.

#java #data-structures #leetcode #interview-prep #cheat-sheet #reference-guide #algorithm

January 11, 2026 EN

DFS Mastery: When to Use Global Variables vs Return Values - Complete Interview Guide

Master the critical decision between global variables and return values in DFS algorithms. Learn patterns with interactive visualizations, templates in Java/Python/JavaScript, and real LeetCode examples from 11-year FAANG veteran.

#algorithm #dfs #depth-first-search #tree #graph #interview-patterns #visualization #interactive-learning

January 7, 2025 EN

Depth-First Search (DFS) - Complete Guide with Recursive and Iterative Approaches

Master DFS algorithm with interactive visualizations. Learn recursive and iterative implementations to solve Symmetric Tree, Path Sum, and other classic problems. Complete Java, Python, JavaScript templates for interview success.

#algorithm #dfs #depth-first-search #binary-tree #recursion #stack #visualization #interview

January 6, 2025 EN

Linked List Cycle Detection - Floyd's Fast & Slow Pointer Complete Guide

Master Floyd's Tortoise and Hare algorithm with interactive visualizations. Detect cycles, find cycle start nodes, and solve LeetCode 141, 142, 287 with mathematical proof and multi-language implementations.

#algorithm #linked-list #two-pointers #visualization #interview #cycle-detection #floyd-algorithm

January 6, 2025 EN

LFU Cache - Complete Guide with Interactive Visualization & LRU Comparison

Master the LFU (Least Frequently Used) Cache data structure with interactive visualizations. Learn O(1) get/put operations using HashMap + frequency buckets. Compare LFU vs LRU caching strategies with real-world examples.

#algorithm #data-structure #cache #linked-list #hashmap #visualization #interview #system-design #lfu #lru

January 6, 2025 EN

LRU Cache - HashMap + Doubly Linked List Complete Guide

Master the LRU Cache data structure with interactive visualizations. Learn how to implement O(1) get and put operations using HashMap and Doubly Linked List. Solve LeetCode 146 with multi-language implementations.

#algorithm #data-structure #cache #linked-list #hashmap #visualization #interview #system-design

January 6, 2025 EN

Binary Tree Inorder Traversal - Recursive, Iterative & Morris Solutions

Master binary tree inorder traversal with interactive visualizations. Learn recursive, iterative (stack-based), and Morris O(1) space solutions. Solve LeetCode 94 with complete Java, Python, JavaScript templates.

#algorithm #binary-tree #tree-traversal #inorder #visualization #interview #morris-traversal #bst

January 6, 2025 EN

Binary Tree Postorder Traversal - Recursive, Iterative & Morris Solutions

Master binary tree postorder traversal with interactive visualizations. Learn recursive, iterative (two-stack & reverse), and Morris O(1) space solutions. Solve LeetCode 145 with complete Java, Python, JavaScript templates.

#algorithm #binary-tree #tree-traversal #postorder #visualization #interview #morris-traversal

January 6, 2025 EN

Binary Tree Preorder Traversal - Recursive, Iterative & Morris Solutions

Master binary tree preorder traversal with interactive visualizations. Learn recursive, iterative (stack-based), and Morris O(1) space solutions. Solve LeetCode 144 with complete Java, Python, JavaScript templates.

#algorithm #binary-tree #tree-traversal #preorder #visualization #interview #morris-traversal

January 5, 2025 EN

Trie (Prefix Tree) Complete Guide - Master String Operations in O(m) Time

Master Trie data structure with interactive visualizations. Learn insert, search, startsWith operations. Solve LeetCode 208, 211, 212 with efficient prefix matching. Complete JavaScript, Java, and Python implementations.

#algorithm #trie #prefix-tree #visualization #interview #string #data-structure

January 4, 2025 EN

Difference Array Complete Guide - Master O(1) Range Updates

Master the difference array technique with interactive visualizations. Solve LeetCode 370, 1109, 1094, 3453. Learn the inverse relationship with prefix sum, sweep line algorithms. Complete JavaScript, Java, and Python implementations for range update and geometric problems.

#algorithm #difference-array #prefix-sum #visualization #interview #array #range-update

January 4, 2025 EN

Prefix Sum Complete Guide - Master Range Queries in O(1) Time

Master prefix sum technique with interactive visualizations. Solve LeetCode 303, 560, 525, 974 with O(1) range queries. Complete JavaScript, Java, and Python implementations for subarray problems.

#algorithm #prefix-sum #visualization #interview #array #hashmap #range-query

December 24, 2024 EN

Binary Search Advanced - The Two-Segment Property

Master the true essence of binary search: the two-segment property. Learn how binary search works on unsorted arrays like rotated arrays, peak finding, and answer space problems. LeetCode 33, 162, 378, 875, 1011 with detailed solutions.

#algorithm #binary-search #visualization #interview #advanced #two-segment

December 23, 2024 EN

Binary Search Fundamentals - Master the Universal Template

Master binary search with one universal template. Interactive visualizations for lower bound, upper bound, first/last occurrence. Solve LeetCode 34, 35, 74 with confidence. Complete JavaScript, Java, and Python implementations.

#algorithm #binary-search #visualization #interview #searching #template

December 19, 2024 EN

Largest Rectangle in Histogram - Three Solutions with Interactive Visualization

Master LeetCode 84 with three progressively optimized solutions: three-pass, two-pass, and one-pass monotonic stack approaches. Interactive visualizations help you understand how to find left/right boundaries efficiently.

#algorithm #monotonic-stack #stack #interview #leetcode #java #python #javascript #visualization

December 18, 2024 EN

Monotonic Stack - Complete Interview Guide

Master the Monotonic Stack pattern for coding interviews. Learn Next Greater Element (LC 496, 503), Daily Temperatures (LC 739), Largest Rectangle in Histogram (LC 84), and Trapping Rain Water (LC 42) with interactive visualizations.

#algorithm #monotonic-stack #stack #interview #leetcode #java #python #javascript

December 18, 2024 EN

Queue and Stack Conversion - Complete Interview Guide with Animations

Master the classic interview problems: Implement Queue using Stacks (LC 232) and Implement Stack using Queues (LC 225). Interactive visualizations show how FIFO and LIFO can transform into each other.

#algorithm #stack #queue #interview #leetcode #java #python #javascript #data-structure #visualization

December 18, 2024 EN

Stack Fundamentals & Design Patterns - Complete Interview Guide

Master stack data structure for coding interviews. Learn Valid Parentheses (LC 20), Evaluate RPN (LC 150), Min Stack (LC 155), and Stack/Queue conversions with interactive visualizations and reusable templates.

#algorithm #stack #interview #leetcode #java #python #javascript #data-structure

December 11, 2024 EN

Variable Size Sliding Window - Complete Guide for Interview

Master the Variable Size Sliding Window pattern for coding interviews. Learn to solve LC 76 (Minimum Window Substring), LC 487 (Max Consecutive Ones II) and more with reusable templates.

#algorithm #sliding-window #interview #leetcode #java #python #javascript

December 9, 2024 EN

Java PriorityQueue: How It's Implemented with a Binary Heap

Deep dive into Java's PriorityQueue implementation: understand siftUp, siftDown operations with interactive visualizations. Learn how the JDK uses binary heaps for efficient priority queue operations.

#java #data-structure #heap #priority-queue #visualization #jdk-source-code #algorithm

December 5, 2024 EN

Heap Sort Algorithm: The Complete Visual Guide to Mastering Heaps

Master Heap Sort through interactive visualizations: from binary heap fundamentals to MAX-HEAPIFY, BUILD-MAX-HEAP, and complete sorting. Includes step-by-step animations and code in JavaScript, Java, Python.

#algorithm #sorting #heap #data-structure #visualization #binary-tree #priority-queue

December 2, 2024 EN

Fixed Size Sliding Window - Complete Guide with Visualization

Master the Fixed Size Sliding Window pattern with interactive visualization. Learn to solve LeetCode 1456 (Max Vowels) and LC 2653 (Subarray Beauty) effectively.

#algorithm #sliding-window #visualization #interactive learning #leetcode #java #counting-sort

November 29, 2024 EN

Quick Sort Algorithm - Complete Guide with 5 Partition Variants

Master Quick Sort with 5 partition schemes: Lomuto, Hoare, Three-Way (Dutch National Flag), Median-of-Three, and Dual-Pivot. Interactive visualizations and code implementations in JavaScript, Java, and Python.

#algorithm #sorting #visualization #computer-science #divide-and-conquer

November 22, 2024 EN

Welcome to Walking in Code - Interactive Programming Tutorials

Discover a new way to learn algorithms and system design through interactive visualizations. Created by a senior engineer with 11+ years at Microsoft, Booking.com, and Alibaba.

#programming tutorial #interactive learning #algorithms #system design #software engineering

All Tags

#algorithm #graph #dfs #bfs #data-structure #visualization #interview #leetcode #topological-sort #java #data-structures #interview-prep #cheat-sheet #reference-guide #depth-first-search #tree #interview-patterns #interactive-learning #binary-tree #recursion #stack #linked-list #two-pointers #cycle-detection #floyd-algorithm #cache #hashmap #system-design #lfu #lru #tree-traversal #inorder #morris-traversal #bst #postorder #preorder #trie #prefix-tree #string #difference-array #prefix-sum #array #range-update #range-query #binary-search #advanced #two-segment #searching #template #monotonic-stack #python #javascript #queue #sliding-window #heap #priority-queue #jdk-source-code #sorting #interactive learning #counting-sort #computer-science #divide-and-conquer #programming tutorial #algorithms #system design #software engineering