Each vertex of a **d**-dimensional hypercube is
connected to d other vertices. In a parallel machine with a
hypercube topology, there is a single processor at each node, and
it is linked to d other processors. An alternative design is to
place a ring of d processors at each vertex, linking the
i processor to the neighboring
vertex along dimension i. The result
is a topology known as a * cube-connected cycle* (CCC)
(Figure 22).
Every node in a CCC is
connected to 3 other nodes: its
two neighbors in the ring plus the node in the neighboring
vertex. Thus a CCC has a constant degree, no matter how many
nodes are in the topology.

(a) What is the diameter of a CCC (assume bidirectional communication).

(b) How many nodes are in a general n-dimensional CCC?

(c) Draw a picture of a 4-dimensional CCC.