Quiz 2, Thursday, 10/1
(20 minutes. Open notes)

As isolated vertex in a graph is one that has no neighbors.
Write a method for the myListGraph class called
isolatedVertices that returns the isolated vertices
in the graph, stored in a StringLinkList object.
In other words, the first line of the method should be:
public StringLinkList isolatedVertices()

What is the worst case running time of the above method, as a function
of n, the number of vertices in the graph.
Justify your answer with a onesentence explanation.