I could not find it but there was an old blog post complaining about this question because it was an open topic in computer science for more than ten years, and

I could not find it but there was an old blog post complaining about this question because it was an open topic in computer science for more than ten years, and if one is not familiar with it they are essentially asking the interviewee to be smarter than then all the people in the computer science world in the 1960's or to be an actor and pretend to figure it out in 30 minutes or less.