I emailed the recruiter and was set up with a phone interview. The interviewer was hard to understand, although much of the interview was conducted using an online collaborative text editor.

The interview included the following questions:

• A question on hexadecimal arithmetic.
• Given the root of some binary tree, write an algorithm to determine whether that tree is a BST.
• Why do you want to work at Quora?

The questions were not unreasonable. However, I didn't formally prepare for the interview and thus didn't perform as well as I wanted.

The hexadecimal arithmetic one. I had never done any hexadecimal math by hand and was thus thrown off.