public static int?[,] GetShortestPaths(DirectedWeightedGraph graph)
{
int n = graph.NodesCount;
for (int i = 0; i < n; i++)
{
graph.AddEdge(n, i, 0);
}
var weights = BellmanFord.GetShortestPaths(graph, n);
if (weights == null)
{
return null;
}
graph.RemoveNode(n);
var reweightedGraph = new DirectedWeightedGraph();
foreach (var edge in graph.GetEdges())
{
reweightedGraph.AddEdge(edge.StartNode, edge.EndNode, edge.Weight + weights[edge.StartNode].Value - weights[edge.EndNode].Value);
}
var distances = new int?[n, n];
for (int i = 0; i < n; i++)
{
int j = 0;
foreach (var distance in Dijkstra.Find(reweightedGraph, i))
{
distances[i, j] = distance - weights[i] + weights[j];
j++;
}
}
return distances;
}