AWS SDE-1 experience. Hope it helps someone.

I was frankly surprised by the bar of AWS, it was tougher than FB new grad (got an offer there) amongst other companies. Had heard the opposite.

Online Assessment:

• 2D matrix question: multiple starting points, multiple end points. You can start from any point and can end at any point. Find the shortest distance from any starting point to any end point. (some blocks were not accessible.)
• 2 sum modification, but had a long story behind it
  (Passed all cases for both)
  Explain the approach. (15 minutes given for this)
  Some work styled survey. (All MCQs.)

Phone Screen:

• Was asked a hard question and a medium question. (started right after introducing himself.)
• https://leetcode.com/problems/maximum-frequency-stack/
• https://leetcode.com/problems/single-number-ii Extend it to all numbers appearing k times except 1.

Onsite:

Round 1:

• Minimum Spanning Tree Question.
• LP Questions.

Round 2:

• LP Questions for about 10 minutes.
• https://leetcode.com/problems/house-robber-ii
• Was asked another question on gcd amongst multiple elements in 2 arrays, since I solved the first one quickly.

Lunch

Round 3:

• LP questions for the first 10-15 minutes.
• System Design question. The interviewer was digging deep into the subparts and kept on adding new features to see how I would integrate them in the design that I proposed initially.

Round 4:

• A lot of LP Questions.
• Basic Calculator II (the medium one).

Round 5:

• Few LP questions.
• https://leetcode.com/problems/cheapest-flights-within-k-stops/ (The interviewer was happy I knew Dijkstra, did not ask me to code the entire solution, just the Dijkstra part.)
• Was asked - remove K digits after this.

I really liked the entire process. I could not figure out which one was the bar raiser though.
I think I got more questions because I solved the first ones quickly. The interviewers were well prepared with the second question.

Please do ask me any questions that you may have. Would love to help!

EDIT: Got the offer!
Now that I have received the offer, here are a few personal thoughts.

I think the bar varies from team to team. Had heard that Amazon focuses more on traditional stuff (BFS/DFS, heaps, 2D matrices, etc), but I was asked DP, bit manipulation (phone screen), Dijkstra and MST (which is a wholesome range, in my opinion). My suggestion would be to focus on LP and make sure you know your stuff in System design (they can ask anything about any part of your system).
For eg: if you use a CDN (dont just say it for the sake of it, know a few things about it), if you propose a recommender system, know a few things about CRON jobs and what those are and how they will run, etc.
How I prepared: It was not an Amazon specific preparation, I did a lot of Leetcode questions, made sure I understood every component in the System design and the major things associated with them (this takes some time).
Focused on the LP for Amazon interview and had 2 scenarios ready for each LP. Hoped for the best!