Let's consider the cost model for flooding to be directly proportional to the total number of times nodes have to process a packet (either send or receive). What is the order of the worst and best case cost of sending a message from any node to any other node (not including reply messages) within this model? What are the topologies that produces these two cases? Assume there are N nodes in the network; the answers should be in terms of O(f(N)).

Trivial cases such as node A sends to node B, which is its only neighbor, will not be accepted, because they cannot be generalized!