I went through three rounds of interviews:

• Two technical interviews with software engineers
• One interview with HR
• The final interview with the head of R&D himself.

I answered all the technical questions efficiently, so I don't think my lack of an offer was due to that.

As other interviews posted here suggest, be wary of the "why Bloomberg" question. I'm guessing my answer to that was the reason I was rejected.

It's a little hard not to be a bit miffed about it since all signs were going very well, only to receive a rejection without a real clue as to why.

Validate a BST.

From post, pre, and in-order traversals, make the tree given. Solve for the sqrt.