One phone screen.

I had applied a long time back. A recruiter called me to know my strengths and skill set, then passed me on to another recruiter who took some time to set up a phone screen. It was a half-hour phone screen.

I waited for a day, then inquired and received a "ding" email.

Given that I had other companies who were interested in me, I had to make time for the phone screening by de-prioritizing other companies. Unless they pursue you strongly, don't bother wasting your time.

Implement a peek function using an existing iterator's next() and hasNext() functions.

The interviewer was interested in correct syntax.