public void FloydWarshall_WhenNegativeEdge_ThenEdgeIncluded()
{
// given
double[,] distances = new double[, ] {
{ 0.0, 4.0, inf, 9.0, 11.0, 12.0, 16.0, 14.0, 14.0, 24.0 },
{ 8.0, 0.0, inf, 5.0, 7.0, 8.0, 12.0, 10.0, 10.0, 20.0 },
{ 7.0, 11.0, 0.0, 4.0, 6.0, 7.0, 8.0, 9.0, 9.0, 19.0 },
{ 3.0, 7.0, inf, 0.0, 14.0, 7.0, 11.0, 5.0, 9.0, 19.0 },
{ 1.0, 5.0, inf, -2.0, 0.0, 1.0, 5.0, 3.0, 3.0, 13.0 },
{ 0.0, 4.0, inf, -3.0, 11.0, 0.0, 4.0, 2.0, 2.0, 12.0 },
{ 7.0, 11.0, inf, 4.0, 18.0, 7.0, 0.0, 9.0, 9.0, 19.0 },
{ 2.0, 6.0, inf, -1.0, 13.0, 2.0, 6.0, 0.0, 4.0, 14.0 },
{ -2.0, 2.0, inf, -5.0, 9.0, 2.0, 6.0, 0.0, 0.0, 10.0 },
{ 10.0, 14.0, inf, 7.0, 21.0, 10.0, 3.0, 12.0, 12.0, 0.0 }
};
Dictionary <(Vertex <int>, Vertex <int>), double> expected =
fromMatrix(undirectedGraph, distances);
directedGraph.AddEdgeBetween(directedGraph[8], directedGraph[3],
new Weighted(-5.0));
// when
Dictionary <(Vertex <int>, Vertex <int>), double> result =
ShortestPaths.FloydWarshall(directedGraph);
// then
result.Should().BeEquivalentTo(expected);
}
public void FloydWarshall_WhenUndirectedGraph_ThenAllShortestPathsLengths()
{
// given
double[,] distances = new double[, ] {
{ 0.0, 4.0, inf, 3.0, 11.0, 10.0, inf, 8.0, 12.0, inf },
{ 4.0, 0.0, inf, 7.0, 7.0, 8.0, inf, 10.0, 10.0, inf },
{ inf, inf, 0.0, inf, inf, inf, 8.0, inf, inf, 11.0 },
{ 3.0, 7.0, inf, 0.0, 8.0, 7.0, inf, 5.0, 9.0, inf },
{ 11.0, 7.0, inf, 8.0, 0.0, 1.0, inf, 3.0, 3.0, inf },
{ 10, 8, inf, 7.0, 1.0, 0.0, inf, 2.0, 2.0, inf },
{ inf, inf, 8.0, inf, inf, inf, 0.0, inf, inf, 3.0 },
{ 8.0, 10.0, inf, 5.0, 3.0, 2.0, inf, 0.0, 4.0, inf },
{ 12.0, 10.0, inf, 9.0, 3.0, 2.0, inf, 4.0, 0.0, inf },
{ inf, inf, 11.0, inf, inf, inf, 3.0, inf, inf, 0.0 }
};
Dictionary <(Vertex <int>, Vertex <int>), double> expected =
fromMatrix(undirectedGraph, distances);
// when
Dictionary <(Vertex <int>, Vertex <int>), double> result =
ShortestPaths.FloydWarshall(undirectedGraph.AsDirected());
// then
result.Should().BeEquivalentTo(expected);
}