Round 1: System Design.

First, the interviewer asked me about my current company's projects, covering topics like how to handle too many requests and multiple writing requests on the same object.

Then, they asked me to design a mechanism to crawl two websites (follow-up: a lot of websites).

Round 2: Coding.

Implement a function to add files to a file management system.

Round 3: Lunch & Interview, Coding.

First question: Serialize and deserialize a binary tree.

Second question: Write a function to find spam emails (emails sent from incorrect names, like "Micr0s0ft" or "amezon").

System design. First, the interviewer asked me about my current company's projects, like how to handle too many requests and multiple writing requests in the same object, etc. Then, he asked me to design a mechanism to crawl two (follow-up: a lot of) websites.

Implement a function to add files to a file management system.

Serialize and deserialize a binary tree.

Write a function to find spam email (emails sent from wrong names like “Micr0s0ft” or “amezon”).

Implement a calculator with +, *, (, and ).