Meta onsite Product E5 | US

My Meta onsite interview experience for a Product E5 position in the US:

Coding Round 1:

1. Nested List Sum: Calculate the sum of values in a nested list, multiplying each value by its depth.
2. Lowest Common Ancestor (LCA): Find the LCA of two nodes in a binary tree. I provided fully functional, near-optimal solutions for both questions. I required one hint for question 2 and did not have time to run tests or discuss time/space complexity.

Coding Round 2:

1. Subsets: Generate all subsets of an integer array.
2. Shortest Path in 2D Matrix: Find the shortest path in a 2D matrix with obstacles and return the path coordinates. I provided fully functional, optimal solutions for both questions. I went slightly overtime. I made some mistakes in analyzing space complexity for both questions.

Behavioral Round:

1. Proudest Project: Describe your proudest project.
2. Changing Requirements: Describe a situation where project requirements changed.
3. Accepting Feedback: Describe a time when you accepted feedback to improve a mistake.
4. Additional Behavioral Question: There was one additional behavioral question. I was experiencing fatigue and provided a suboptimal example for one question due to a lack of time to fully understand the question. I felt and sounded low energy.

System Design Round: Design a news feed for images only, requiring low latency. I completed the high-level design, clarified requirements effectively, and asked good questions. I took the lead throughout, except for interruptions that prevented a deep dive into the API design. I did not have much time for a deep dive.