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Coding Interview Preparation

“In preparing for battle I have always found that plans are useless, but planning is indispensable.” — Dwight D. Eisenhower

🎯 What Coding Interviews Test

Coding interviews evaluate far more than your ability to write code. Interviewers assess:

┌─────────────────────────────────────────────────────────┐
│              CODING INTERVIEW EVALUATION                │
├─────────────────────────────────────────────────────────┤
│                                                         │
│  1. Problem Solving (40%)                               │
│     ├── Understanding the problem                       │
│     ├── Breaking it down                                │
│     ├── Identifying patterns                            │
│     └── Handling edge cases                             │
│                                                         │
│  2. Technical Knowledge (30%)                           │
│     ├── Data structure selection                        │
│     ├── Algorithm design                                │
│     ├── Complexity analysis                             │
│     └── Language proficiency                            │
│                                                         │
│  3. Communication (20%)                                 │
│     ├── Explaining your approach                        │
│     ├── Asking clarifying questions                     │
│     ├── Discussing trade-offs                           │
│     └── Responding to hints                             │
│                                                         │
│  4. Code Quality (10%)                                  │
│     ├── Readable variable names                         │
│     ├── Clean structure                                 │
│     ├── Error handling                                  │
│     └── Testing                                         │
│                                                         │
└─────────────────────────────────────────────────────────┘

📖 In This Section

GuideWhat You’ll Learn
Data StructuresComplete reference for arrays, trees, graphs, hash maps, and more
Problem Patterns15+ patterns that solve 90% of interview problems
Complexity AnalysisBig-O notation, amortized analysis, space-time trade-offs
Coding FrameworkStep-by-step approach to any coding problem

📊 Problem Difficulty Distribution

Based on analysis of recent FAANG interviews (2024-2026):

Easy    ████████░░░░░░░░░░░░  20%  (Warm-up, usually < 10 min)
Medium  ████████████████░░░░  55%  (Core of most interviews)
Hard    █████░░░░░░░░░░░░░░░  25%  (Differentiator for senior roles)

Key insight: You don’t need to solve Hard problems to get hired. Consistently solving Medium problems with clean code and good communication is enough for most offers.

By Platform

  • LeetCode: Top 150 (Blind 75 + NeetCode 150)
  • HackerRank: Interview Preparation Kit
  • CodeForces: Div 2 A-C problems for speed

By Topic Priority

  1. Arrays & Strings — Most common, master these first
  2. Trees & Graphs — Second most common, essential for Google
  3. Dynamic Programming — Hard but predictable patterns
  4. Linked Lists — Common for fundamentals testing
  5. Stacks & Queues — Often combined with other structures
  6. Hash Maps — Used in almost every problem as a component

⏱️ Time Management in Interviews

For a 45-minute coding interview:

┌─────────────────────────────────────────────┐
│         TIME ALLOCATION (45 min)            │
├─────────────────────────────────────────────┤
│  Understanding & Questions    5 min (11%)   │
│  Approach & Discussion        8 min (18%)   │
│  Coding                      20 min (44%)   │
│  Testing & Edge Cases         7 min (16%)   │
│  Follow-up / Optimization     5 min (11%)   │
└─────────────────────────────────────────────┘

🔗 Cross-References