public void DijkstraSPTest()
{
var graph = new EdgeWeightedDigrap(8, new[]
{
"4 5 0.35",
"5 4 0.35",
"4 7 0.37",
"5 7 0.28",
"7 5 0.28",
"5 1 0.32",
"0 4 0.38",
"0 2 0.26",
"7 3 0.39",
"1 3 0.29",
"2 7 0.34",
"6 2 0.40",
"3 6 0.52",
"6 0 0.58",
"6 4 0.93"
});
var dijkstra = new DijkstraSP(graph, 0);
Assert.AreEqual(dijkstra.HasPathTo(6), true);
dijkstra.DistTo(6);
var builder = new StringBuilder();
foreach (var data in dijkstra.PathTo(6))
{
builder.AppendFormat("->{0}", data.To);
}
}
public DijkstraSP(EdgeWeightedDigrap graph, int s)
{
distTo = new double[graph.V];
edgeTo = new DirectedEdge[graph.V];
minPq = new IndexMinPq<double>(graph.V);
for (int i = 0; i < graph.V; i++)
{
distTo[i] = Double.MaxValue;
}
distTo[s] = 0;
minPq.Insert(0, 0);
while (!minPq.IsEmpty())
{
Visit(graph, minPq.DelMin());
}
}
private void Visit(EdgeWeightedDigrap graph, int v)
{
foreach (DirectedEdge edge in graph.Adj(v))
{
int w = edge.To;
if (distTo[w] > distTo[v] + edge.Weight)
{
edgeTo[w] = edge;
distTo[w] = distTo[v] + edge.Weight;
if (minPq.Contains(w))
{
minPq.Change(w, distTo[w]);
}
else
{
minPq.Insert(w, distTo[w]);
}
}
}
}
public SP(EdgeWeightedDigrap graph, int s)
{
}
