I went through three rounds of phone interviews. It took about two months from the first phone screen to the third phone screen. The oral questions usually included a lot of performance-based analysis, like Big O notation for sorting, as well as other data structure questions. They also asked me to write programs on the fly using Google Docs, which they could see in almost real-time.

How do you remove duplicates in a large array?

Write a program to merge two unsorted large arrays.