Searching certain items starts on layer n, continues layer n-1, and so on until layer 0. For instance, let’s assume that we want to find item 11.We start on layer 2 and continue running on this layer until we find a node >= 11. Since the value 11 doesn’t exist on layer 2, we search for an item less than 11 and we find 10.We get down on layer 1 and continue searching. Based on the same logic we find item 10 again. Layer 1 doesn’t contain item 11 either. If it had contained it then we would have stopped the search.We go down again, this time to layer 0 (the base layer containing all items), and continue searching until we find item 11. The following figure depicts our search path: