Amazon Intern interview questions

I got a email for noticing me which I got a interview in two days. when i had the interview, the interview was the phone interview, and i had two phone call and each is 45 mins with two people, and got 15 mins for break after a call. The interview was used the online white broad for coding.

I submitted my resume through the website and get back from the recruiter after one month. There are two back to back phone interviews, each last 45 minutes. The questions are generally data structures such as Hashtble and how to handle collison and some OOP concept like what is polymorphism, encapsulation and inheritance.