/// <summary>
/// Add a new vertex to the graph and returns it.
///
/// Complexity: 1 insertion.
/// </summary>
/// <returns>Create vertex</returns>
public virtual IVertex AddVertex()
{
IVertex v = VertexProvider.ProvideVertex();
VertexOutEdges.Add(v, new EdgeCollection());
return(v);
}
/// <summary>
/// Add a new vertex to the graph and returns it.
///
/// Complexity: 1 insertion.
/// </summary>
/// <returns>Create vertex</returns>
public virtual void AddVertex(IVertex v)
{
if (v == null)
{
throw new ArgumentNullException("vertex");
}
if (VertexOutEdges.Contains(v))
{
throw new ArgumentException("vertex already in graph");
}
VertexProvider.UpdateVertex(v);
VertexOutEdges.Add(v, new EdgeCollection());
}