public class Vertex
{
	private String v;
	private StringLinkList neighbors;

	// creates a Vertex object whose name is newVertex and
	// whose neighbor list is empty
	Vertex(String newVertex)
	{
		v = new String(newVertex);
		neighbors = new StringLinkList();
	}

	// Adds a neighbor 
	void addNeighbor(String newVertex)
	{
		neighbors.insertFirst(newVertex);
	}

	// Returns the number of neighbors
	int numberOfNeighbors()
	{
		return neighbors.size();
	}
}