Shipping and Receiving

You are given a two-dimensional list of integers ports where ports[i] represents the list of ports that port i is connected to. You are also given another two-dimensional list of integers shipments where each list of the form [port_i, port_j] which means there is a shipment request from port_i to port_j.

Given that the cost to ship port_i to port_j is the length of the shortest path from the two ports, return the total cost necessary to send all the shipments. If there’s not a path between two ports, the cost is 0.

Constraints

• p ≤ 100 where p is the length of ports
• s ≤ 10,000 where s is the length of shipments

https://binarysearch.com/problems/Shipping-and-Receiving

Examples

Example 1

Input

• ports =

[[list([2, 3]),list([2]),list([1, 0]),list([4]),list([])]]

• shipments =

[[2,4]]

Output

• answer = 3

Solution