public void DistanceTo_WhenPathExistsBetween0And4_WillBeSumOfWeightsInPath()
{
EdgeWeightedDigraph digraph = new EdgeWeightedDigraph(5);
digraph.AddEdge(new DirectedEdge(0, 1, 2.5));
digraph.AddEdge(new DirectedEdge(1, 2, 3.25));
digraph.AddEdge(new DirectedEdge(2, 3, 1.25));
digraph.AddEdge(new DirectedEdge(3, 4, 2));
DijkstraShortestPath dijkstra = new DijkstraShortestPath(digraph, 0);
Assert.AreEqual(9, dijkstra.DistanceTo(4));
}
public void DistanceTo_WhenNoPathExists_WillBePositiveInfinity()
{
EdgeWeightedDigraph digraph = new EdgeWeightedDigraph(5);
digraph.AddEdge(new DirectedEdge(0, 1, 2.5));
digraph.AddEdge(new DirectedEdge(1, 2, 3.25));
digraph.AddEdge(new DirectedEdge(1, 4, 4.75));
digraph.AddEdge(new DirectedEdge(2, 3, 1.25));
digraph.AddEdge(new DirectedEdge(3, 4, 2));
DijkstraShortestPath dijkstra = new DijkstraShortestPath(digraph, 4);
Assert.AreEqual(double.PositiveInfinity, dijkstra.DistanceTo(0));
}