The Ultimate Guide to Amazon SDE-1 Interview Questions (USA)

Navigating Amazon's SDE-1 interviews in the U.S. can feel overwhelming, but thorough preparation can significantly boost your confidence. Here's a structured breakdown of what to expect and how to ace it!

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Stage 1: Online Assessment (OA)

Format:

• Coding: Typically two questions (easy-medium difficulty), involving arrays, sliding windows, heaps, or graph traversal (BFS/DFS).

• Work-Style Simulation: Scenario-based questions focusing on Amazon’s Leadership Principles.

Stage 2: Phone / Virtual Screen

Duration: ~60 minutes

Structure:

• Behavioral Questions (15-20 min):

  • Format: STAR (Situation, Task, Action, Result).

  • Typically covers 2-3 Leadership Principles like Customer Obsession, Ownership, and Dive Deep.

• Coding Questions (40-45 min):

  • Topics: Arrays/strings (e.g., Two Sum, Anagram Counting), Graphs/Trees (e.g., Decode Ways, BFS matrix traversal).

Stage 3: Onsite / Virtual Onsite Loop

Format: Typically 3–5 interviews (50 minutes each)

A. Behavioral / Leadership

Common topics include:

• Customer Obsession

• Ownership

• Dive Deep

• Handling ambiguity and conflicts

B. Coding Rounds

Expect 2–4 questions, often medium to medium-hard level. Examples include:

• Arrays/Strings: Two Sum, Median of Two Sorted Arrays

• Dynamic Programming: Decode Ways, House Robber

• Trees/Graphs: Same Tree, Minesweeper, DFS/BFS problems

• Additional challenges like Currency Converter, Rotated Array Search

Interviewers often ask for follow-up variations or alternative solutions.

C. Design & Fundamentals

• Basic system design or API optimization

• Core CS fundamentals questions (OOP, databases, OS concepts like mutex and semaphore)

D. Bar-Raiser Round

A senior Amazon interviewer assesses both technical ability and alignment with Leadership Principles.

Sample Questions by Category

Category Sample Questions Arrays/Strings Two Sum, Median of Two Sorted Arrays, Longest Consecutive Sequence Dynamic Programming Decode Ways, House Robber Graphs/Trees Same Tree, Tic-Tac-Toe design, Minesweeper Miscellaneous Currency Converter, Rotated Sorted Array System Design/API Low-scale service design, API optimization CS Fundamentals OOP principles, mutex vs semaphore, database basics Behavioral STAR-format questions emphasizing Leadership Principles

Tips for Preparation

1. Coding Practice:

   • LeetCode Top 100–200 problems (arrays, DP, graphs, trees).

   • Practice explaining your solution clearly, including time/space complexity.

2. Behavioral Questions:

   • Prepare 1–2 strong STAR stories per Amazon Leadership Principle.

3. System Design/Fundamentals:

   • Understand low-level design, OOP concepts, database fundamentals, and OS basics.

4. Mock Interviews:

   • Conduct practice sessions with peers or through online platforms.

Quick Summary

• Online Assessment: Coding + Leadership principles scenarios

• Phone & Onsite: Mixed rounds covering DSA, system design, fundamentals, and behavioral questions

• Key to Success: Master LeetCode, practice STAR-format responses, review design basics, and perform mock interviews

Happy interviewing!