Situation: Crouching and putting some books I borrowed back to the shelf. There are some windows on my left.
Alternative situations: I am looking through bookshelf in front of me, another bookshelf is behind me, trying to find a book about sports. Directly in front of the bookshelf, looking for a sherlock holmes book.
Question: Is the amount of lamps on top of the bookshelf in front of me odd or even?