Intel Corporation Software Engineer Intern interview questions

I submitted my resume online and was called by the end of the day by one of the members in the intern department. He said they were on a time crunch and has six candidates left to choose from, but my resume appeared better than others and he was wondering if I had time to interview before the end of the day. Luckily I only had one more class for the day, and accepted. The "most difficult" question I was asked (probably because I'm a freshman) was given an array of 100 numbers in order (ie 1,2,3...,99,100) with 99 unique values and 1 duplicate value, how would I find the duplicate? I answered BST and then traverse the left or right child depending on what the root node was. He then asked me the big-Oh of it which is logn. I got a call from the original contact at Intel asking me to join them for the summer about twenty minutes after the phone interview. Got an email the following week for me to consent to a background check and then the week after that I was formally given an offer.

First there was a phone interview with hiring manager for 30 minutes. After a week there was a phone interview which was a technical round lasting for about an hour. Questions ranged from java, Data structures etc.