Google Ingeniero De Software interview questions

2 Telephonic Interviews. I am an Electrical Engineering Student with more RTOS/ARM background. The first interview was conducted by an Electrical engineer. He asked me questions about what an RTOS is, how to handle interrupts, use of "static" in C and C++, an algorithms question on finding duplicates in an array.

This was the second phone interview, the first being with a recruiter. I spoke with an engineer at google and he asked me some general c++ questions (malloc/polymorphism/virtual functions/etc) and then gave me a problem to write an algorithm for (find the next in a sequence of numbers). The interviewer gave me some hints along the way, but unfortunately I was stuck for a good 10 minutes on one of his hints that turned out to be a misunderstanding between us. I verbalized everything I was doing along the way to try to make things as clear as possible. I didn't get the answer correct in the end. He told me how to see where the sequence goes, but I don't understand how he would decide to use that approach. I feel like i would have no problem writing the algorithm but i don't know how he arrived at the solution. It wasn't a very positive experience overall. i don't expect to be asked for an in-person interview.