LAN Services System builds the routing tables for the nodes in a computer network, based on shortest-path
routing from an any node to all other nodes, where path distance is measured by hop weight, that is, the total
weight of edges in a path. The input for this problem is a text file that holds the connectivity information for all
the nodes in the network, as in the following example:
[login to view URL]: [login to view URL] [login to view URL] [login to view URL]
Which indicates three network nodes that are connected to [login to view URL], that is, three nodes that are one hop
away. Wire length is given by the absolute value of difference between destination and source in last segment of
node address. So that, the wire length between [login to view URL] and first node in the example above is 1. The
routing table for the node at address A is a set of pairs (B, C), which indicates that, to route a message from A to
B, the next node to send to (on the shortest path from A to B) is C. Your program should output the routing
table for each node in the network, given an input list of node connectivity lists, each of which is input in the
syntax as shown above, one per line.