public static IEnumerable <string> Get_First_Mutual_Branch_Point_Backwards(string vertex, BidirectionalGraph <string, TaggedEdge <string, Tag> > graph)
{
Contract.Requires(graph != null);
if (!graph.ContainsVertex(vertex))
{
yield break;
}
int inDegree = graph.InDegree(vertex);
if (inDegree < 2)
{
yield break; // the provided vertex is not a mergePoint
}
if (inDegree == 2)
{
string s1 = graph.InEdge(vertex, 0).Source;
string s2 = graph.InEdge(vertex, 1).Source;
if (s1 != s2)
{
HashSet <string> branchPoints1 = new HashSet <string>();
HashSet <string> branchPoints2 = new HashSet <string>();
foreach (string v in Get_First_Branch_Point_Backwards(s1, graph))
{
branchPoints1.Add(v);
}
foreach (string v in Get_First_Branch_Point_Backwards(s2, graph))
{
branchPoints2.Add(v);
}
foreach (string mutual in branchPoints1.Intersect(branchPoints2))
{
yield return(mutual);
}
}
}
else
{
Console.WriteLine("WARNING: Get_First_Mutual_Branch_Point_Backwards: multiple merge points at this the provided vertex " + vertex);
}
}
public TEdge InEdge(TVertex v, int index) => _graph.InEdge(v, index);
