public void TopologicalSortOnWeightedGraph()
{
var vertices = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
var graph = new DirectedWeightedALGraph <int, int>();
graph.AddVertices(vertices);
// Graph is:
// 1 -> 3, 4
// 2 -> 5
// 2 <- 3, 6
// 3 -> 2, 6
// 3 <- 1, 4
// 4 -> 3, 6, 7
// 4 <- 1
// 5 -> 7, 8
// 5 <- 2, 8
// 6 -> 2
// 6 <- 3, 4
// 7 -> 4
// 7 <- 5, 8
// 8 -> 7
// 8 <- 5
// 9 ->
// 9 <-
// Edges weight is the sum of the vertices
graph.AddEdge(1, 3, 4);
graph.AddEdge(1, 4, 5);
graph.AddEdge(2, 5, 7);
graph.AddEdge(3, 2, 5);
graph.AddEdge(3, 6, 9);
graph.AddEdge(4, 3, 7);
graph.AddEdge(4, 6, 10);
graph.AddEdge(4, 7, 11);
graph.AddEdge(5, 7, 12);
graph.AddEdge(5, 8, 13);
graph.AddEdge(6, 2, 8);
graph.AddEdge(8, 7, 15);
// Expected topological sort
// 1 4 3 6 2 5 8 7 9
var expected = new int[] { 1, 4, 3, 6, 2, 5, 8, 7, 9 };
var topSort = graph.TopologicalSortSmallestFirst();
for (int i = 0; i < expected.Length; i++)
{
Assert.IsTrue(topSort[i] == expected[i]);
}
}