Cisco Software Engineer Interview Experience — HR Screen, Then a River-Crossing Brainteaser Instead of Coding

I applied for an SDE role on the Switch team.

The first round was over Wedex, 30 minutes, with a female HR person. She asked things like where I live and where I'm eligible to work — that kind of question, nothing about my past experience. At the end I asked her how to prepare for the next round. She said this one would be switch-related, so I should probably brush up on some switching fundamentals.

The second round was with the hiring manager, one hour. There was no coding at all, no past experience questions, and nothing about switching or networking fundamentals. Instead he gave me a brainteaser similar to the classic "horses crossing the river" riddle — basically, there are X horses and Y ladders, and you need to figure out the minimum number of trips to get all the horses from one side to the other. My first attempt came out to 21, and he said that number was too high. My second attempt came out to 11, but it didn't satisfy all the conditions.

There was no third round.

Toward the end of the second round I started to panic a little, and the more I calculated the more confused I got. The interviewer probably noticed. I really didn't expect him to throw a brainteaser at me like that.