Juniper Networks Software Engineer interview questions

Hi i was interviews for Software Engineer role in Juniper Networks, Bangalore. My Profile : 3.5yrs of Exp in Java , J2EE, Struts and 4Months of Exp in ExtJs. I was called by the company HR as she found my resume on the job portal. initially they had setup the telephonic round with Senior Engineer Manger. and below are few question i faced. 1.Explain the Data Structure Model. ?? Why did it evolve. 2.Explain Tree. 3. Traversal of Tree Structure, He asked some in-order traversal of nodes and an example. 4. Write the complete code implementation of the In-order traversal. (Though i explained the pseudo-code, he insisted on the complete code in java. :( . i was not completely efficient in writing it down and convey entire thing on phone ). i explained the recursive algo for this. 5. Next came the Puzzles and Problem solving questions. :) a. Find the repeating element in a given array and number of times it is repeated. I did gave a good answer (use hashmap and counter the value for key) for this quesion but again he wanted a complete code for this explained on phone. :( b. 10 bag of gold coin, where 1 bag has a defective ones. find the odd ones using the balance machine only once. (i did not give a good answer here) c. Some question on double matrix (dont remember it) d. Prove that the number between prime pair is always divisible by 6 (i did not even gave a approach for this) Overall it was a good experience, No question were asked related to Java Language or concepts blah blah.. Prepare well for the puzzle and DS and Algos and u can do well in it. best of luck, Punith

Their hr found my resume online and asked me if I'm interested. two days later we scheduled a phone interview. The interviewer is very nice asked me about my previous projects, some knowledge on networking and C coding.