Meta | E5 | Menlo Park

I received a job offer from Meta, and here is my interview experience:

Phone Screen:

1. A question similar to finding K continuous sum.
2. Valid Word Abbreviation

Onsite Interviews: Round 1:

1. Given an integer array, return the k-th largest element in the array.
2. Given two arrays with costs between two cities (a -> b and b -> a), return the minimum round trip cost between the two cities.

Round 2:

1. Given a 2D matrix with 0 and 1, where 0 is an open path and 1 is an obstacle, find the shortest path between the top-left point and the bottom-right point.
2. Given a binary tree with parent pointers, find the lowest common ancestor (LCA) of two given nodes.

Round 3 (Design): Design a backend system for the latest trending hashtags from Facebook statuses. I discussed multiple design approaches with the interviewer, highlighting the pros and cons of each. I explained my chosen approach in detail, including my use of Redis sorted sets and how they are implemented and utilized.

Round 4: Standard behavioral questions.

Additional Advice:

• I strongly advise spending time on behavioral interviews if you are targeting a senior position. Prepare stories from your past experience and conduct mock interviews.
• Behavioral and system design interviews are very important for leveling up.
• For system design, I prepared using Alex Xu's book and other online resources.
• For coding, discuss all possible solutions and explain why you chose a specific implementation.
• Practice data structures and algorithms (DSA) with a stopwatch.