private int GetLongestLink(IEdge currentEdge, IVertex useVertex, HashSet<IEdge> visitedEdges)
{
if (visitedEdges.Contains(currentEdge))
{
return 0; // if already visited
}
if (useVertex.Campus != null && useVertex.Campus.Color != Color)
{
return 1; // if other player's campus is in the way
}
visitedEdges.Add(currentEdge);
int max = 0;
foreach (IEdge edge in currentEdge.GetAdjacentEdgesSharedWith(useVertex))
{
if (edge.Color != Color)
continue;
// use the vertex on the other side of the edge
int path = GetLongestLink(edge,
edge.Adjacent.Vertices.First(v => v != useVertex),
visitedEdges);
if (max < path)
{
max = path;
}
}
visitedEdges.Remove(currentEdge);
return max + 1;
}