Undergraduate, description:

Solve the all-pairs shortest path problem using the Floyd-Warshall algorithm to the network given in Fig. 4.15(a). Show the distance matrix for each iteration. To make the matrix more readable, relabel the nodes a,b, ..., f for 1,2,... ,6, and z for node 0.

What the heck is this "z for node 0" under the homework discription, no such node exists in the graph, nor is thre additional nodes for the FW algorithm.