I am not sure whether I got the interview through online website or job fair as I did it in both ways.

The first is HR contacted me and we had about one hour chat. Such as which team is most interesting to me, what do I do in my free time, how do I score my programming skills...

The first phone interview is a very junior engineer, two very simple questions all can be find in this website.

1. valid number, (do not consider exponential or space conditions)
2. max subarray sum, Given a array, find the biggest sum of concatenated subarray.
3. max subarray product, Same as #2, juse calculate the product instead of sum.

After a few days, I got the second round phone interview:
This time there were two interviewer, one is senior, the other is a junior. We chated a lot about my projects.

Give a list of words and two individual words, find the shortest distance between the two words within the list of words.
e.g. list =[one, two, three, four, one] find the distance between one and two, so it should be 1.

I tried the hashmap method, the first one is O(n^2). Then I am asked to optimize it. So I made it to be O(n). Then we spent a lot of time on testing the corner cases.