void UpdateInEdgesOfV(int v)
{
foreach (var inEdge in graph.InEdges(v))
{
var u = inEdge.Source;
if (NodeIsInTree(u))
{
continue;
}
IEdge oldEdge;
if (hedgehog.TryGetValue(u, out oldEdge))
{
var oldWeight = weight(oldEdge);
var newWeight = weight(inEdge);
if (newWeight < oldWeight)
{
q.DecreasePriority(u, newWeight);
hedgehog[u] = inEdge;
}
}
else
{
q.Enqueue(u, weight(inEdge));
hedgehog[u] = inEdge;
}
}
}
static IEnumerable <int> Neighbors(BasicGraphOnEdges <TEdge> graph, int s)
{
foreach (TEdge e in graph.OutEdges(s))
{
yield return(e.Target);
}
foreach (TEdge e in graph.InEdges(s))
{
yield return(e.Source);
}
}