Using the network shown and the conventional method discussed in your textbook, what are the first two nodes in the network and why? Now avoid convention and pick the first two nodes that must be part of the correct solution

Why is this the case?

Answer: Convention dictates that a solution begins with node 1 and proceeds to the nearest node, which is node 3 at a distance of 11. Tossing convention out, one should pick the two closest nodes, which in this network are nodes 4 and 5, separated by only 6 units.