Coding Interview Strategies, Walkthroughs and Guides
Welcome to the intervu.dev blog. Here you'll find 75+ LeetCode problem walkthroughs, data structures guides, and company-specific interview preparation strategies. Learn from real coding interview examples and expert tips.
Coding Interview Walkthroughs
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Construct Binary Tree from Preorder and Inorder Traversal
A step-by-step walkthrough of Construct Binary Tree from Preorder and Inorder Traversal as it unfolds in a real coding interview. Learn the recursive reconstruction algorithm, the hash map optimization, and how to avoid common index-tracking mistakes.
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Find Median from Data Stream
A step-by-step walkthrough of the Find Median from Data Stream problem as it unfolds in a real coding interview. Learn the two-heap approach, the rebalancing invariant, and how to simulate a max-heap in Python.
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Largest Rectangle in Histogram
A step-by-step walkthrough of the Largest Rectangle in Histogram problem as it unfolds in a real coding interview. Learn the monotonic stack approach, the sentinel trick, and how to correctly compute rectangle widths.
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Maximum Profit in Job Scheduling
A step-by-step walkthrough of the Maximum Profit in Job Scheduling problem as it unfolds in a real coding interview. Learn the DP + binary search approach, the sorting prerequisite, and how to implement the clean dp-array pattern.
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Minimum Height Trees
A step-by-step walkthrough of the Minimum Height Trees problem as it unfolds in a real coding interview. Learn the leaf-trimming algorithm, why MHT roots are always the tree's center nodes, and how to implement the solution in O(n).
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Serialize and Deserialize Binary Tree
A step-by-step walkthrough of Serialize and Deserialize Binary Tree as it unfolds in a real coding interview. Learn both BFS and DFS approaches, how to encode null nodes, and why the DFS preorder solution is the cleanest interview implementation.
Language Cheat Sheets
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Python Coding Interview Cheat Sheet
Master Python for coding interviews with this complete cheat sheet covering data structures, built-ins, STL patterns, and common algorithm templates. Includes strings, lists, heaps, BFS/DFS, DP, and more.
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Java Coding Interview Cheat Sheet
Master Java for coding interviews with this complete cheat sheet covering data types, strings, arrays, ArrayLists, HashMaps, heaps, sorting, binary search, bit manipulation, and common algorithm templates including BFS, DFS, two pointers, and dynamic programming.
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C++ Coding Interview Cheat Sheet
Master C++ for coding interviews with this complete cheat sheet covering STL containers, algorithms, sorting, binary search, bit manipulation, and common algorithm templates. Covers vectors, maps, heaps, BFS/DFS, DP, and more.
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JavaScript Coding Interview Cheat Sheet
Master JavaScript for coding interviews with this complete cheat sheet covering data types, strings, arrays, objects, maps, sets, sorting, binary search, bit manipulation, and common algorithm templates including BFS, DFS, two pointers, sliding window, and dynamic programming.
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Go Coding Interview Cheat Sheet
Master Go for coding interviews with this complete cheat sheet covering data types, strings, slices, maps, sorting, binary search, bit manipulation, and common algorithm templates including BFS, DFS, two pointers, sliding window, and dynamic programming.
System Design Guides New
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URL Shortener System Design: FAANG Interview Guide (L3–L8)
URL shortener system design walkthrough: requirements, encoding, caching, data model, scalability. Level-calibrated answers from L3 to L8 at FAANG companies.
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Rate Limiter System Design: FAANG Interview Guide (L3–L8)
Design a rate limiter for a system design interview. Covers token bucket vs leaky bucket, sliding window, distributed counters, Redis Lua scripts, failure modes.
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Twitter/X Feed System Design: FAANG Interview Guide (L3–L8)
Design a Twitter/X news feed for your system design interview. Covers fan-out strategies, timeline generation, ranking, caching, and real-time delivery. Used at Meta, Twitter, LinkedIn interviews.
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Key-Value Store & Distributed Cache System Design
Design a distributed key-value store or cache (Redis, Memcached). Covers consistent hashing, eviction policies, replication, partitioning, and failure modes for FAANG interviews L3–L8.
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Search Autocomplete System Design: FAANG Interview Guide (L3–L8)
Design a Search Autocomplete system: trie vs inverted index, prefix ranking, typeahead at scale. Full FAANG/MAANG interview guide covering Google, Amazon, Twitter, LinkedIn — L3 to L8.
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Web Crawler System Design: FAANG Interview Guide (L3–L8)
Design a Web Crawler for your system design interview. Covers BFS frontier, politeness, URL deduplication, and distributed crawl at Google/Bing scale.
Interview Preparation
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FAANG Coding Interview Guide 2026: Google, Meta, Amazon, Netflix & Apple Compared
How Google, Meta, Amazon, Netflix, and Apple coding rounds actually differ in 2026. Company comparison table, 10 patterns, 8-week prep roadmap.
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Data Structures for Coding Interviews: Complete Guide with Patterns, Examples, and Study Plan
Master the 10 data structures that appear in coding interviews. Includes patterns, complexity tables, common mistakes, practice problems, and a 4-week study plan.
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How to Prepare for a Coding Interview in 2026: Roadmap, Study Plan & Checklist
Your 2026 coding interview prep roadmap: study plans for 2 weeks or 3 months, a pre-interview checklist, and the practice strategy most engineers skip.
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How to Master Coding Interviews: Practice Like Real Interviews
Why LeetCode alone isn't enough, what FAANG interviewers actually evaluate, and how to simulate real interview conditions.
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Best Coding Interview Prep Tools (2026) — The Developer's Arsenal
From LeetCode to AI mock interviews — a no-hype guide to the best coding interview prep tools in 2026, including platforms for DSA, system design, behavioral rounds, and mock interview simulation.
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Coding Interview Patterns: The Complete Guide (2026)
Master the 15 most important coding interview patterns in 2026, featuring Python templates, recognition tips, and real LeetCode examples for Two Pointers, Sliding Window, Dynamic Programming, and more.
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Grind 169: Complete Problem List, 10-Week Study Plan & AI Mock Interview Practice
The complete Grind 169 problem list with all 94 additions beyond the Grind 75, organized by topic. Includes a 10-week study plan and one-click AI mock interview practice for every problem.
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Python for Coding Interviews: Data Structures Companion Guide
The Python implementation guide for coding interviews. Built-in tools, templates, patterns, and pitfalls for arrays, hash maps, stacks, queues, heaps, trees, graphs, tries, and union find. Companion to the Data Structures for Coding Interviews guide.
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Supercharge Your LeetCode Practice With a Live AI Mock Interviewer
You already solve LeetCode problems. Now practice presenting them under interview pressure with an AI that probes your thinking, pacing, and trade-offs.
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The Grind 75 Practice Pathway — Practice Every Problem with AI Mock Interviews
Grind 75 tells you what to solve — now practice delivering each problem in a live AI mock interview. Speak, code, and get feedback problem by problem.
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The Anatomy of an AI Interview: How Intervu.dev Helps You Practice Under Pressure
Walk through a full AI mock coding interview: clarification, live coding under pressure, follow-up questions, and the signal-based feedback you receive.
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Why LeetCode Is Not Enough for Coding Interviews (and What to Do Instead)
LeetCode is a training tool, not a simulation. Learn why relying solely on it leaves gaps in communication, debugging, and execution, and how to fix them.
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Master Coding Interviews with Realistic AI Mock Interviews
Stop grinding LeetCode alone. Learn how Intervu.dev bridges the gap between solving problems and performing well in real technical interviews.
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Peer-to-Peer vs AI-Driven Mock Interviews: Which One Prepares You Better?
A breakdown of the pros and cons of human vs AI mock interviews, and how to combine them for maximum success.
Engineering
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How I Built an AI That Conducts Mock Coding Interviews
How intervu.dev was built: the voice pipeline, live code execution, and prompt engineering behind an AI mock interviewer that feels like a real person.
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Eliminating the Mic Activation Delay in a Real-Time AI Interviewer
How pre-warming a WebSocket connection during TTS playback reduced the gap between the AI finishing its sentence and the microphone going live, from ~850ms to under 400ms.
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Fixing the 'Static of Doom': A Deep Dive into Real-time PCM Streaming
How a single misaligned byte and a sneaky WAV header turned a high-fidelity AI interviewer into a wall of white noise, and how it was fixed.