func TestTopologicalSort(t *testing.T) {
h := graph.NewDirected()
addEdge := func(h *graph.DirGraph, i, j int) {
h.AddEdge(graph.VertexId(i), graph.VertexId(j), 1)
}
for i := 1; i < 10; i++ {
h.AddVertex(graph.VertexId(i))
}
addEdge(h, 1, 7)
addEdge(h, 7, 4)
addEdge(h, 4, 1)
addEdge(h, 7, 9)
addEdge(h, 9, 6)
addEdge(h, 6, 3)
addEdge(h, 3, 9)
addEdge(h, 6, 8)
addEdge(h, 5, 8)
addEdge(h, 2, 5)
addEdge(h, 8, 2)
dfs.DirectedDfs(h, graph.VertexId(9), func(v graph.VertexId) {
//fmt.Println(v)
})
s := Scc(h)
fmt.Println(s)
}
func Scc(g *graph.DirGraph) []stack.Stack {
s := stack.New()
n := g.Order()
SCCs := make([]stack.Stack, 0)
visited := make(map[graph.VertexId]bool)
vertices := g.VerticesIter()
for s.Len() != n {
vertex := <-vertices
dfs.DirectedDfs(g, vertex, func(v graph.VertexId) {
if visited[v] == false {
fmt.Println(vertex, v)
s.Push(v)
visited[v] = true
}
})
}
fmt.Println(s)
r := g.Reverse()
visited = make(map[graph.VertexId]bool)
for s.Len() > 0 {
vertex := s.Pop().(graph.VertexId)
scc := stack.New()
if visited[vertex] == false {
dfs.DirectedDfs(r, vertex, func(v graph.VertexId) {
fmt.Println(vertex, v)
if visited[graph.VertexId(v)] == false {
visited[graph.VertexId(v)] = true
fmt.Println(vertex, v)
scc.Push(v)
}
})
}
if scc.Len() > 1 {
SCCs = append(SCCs, *scc)
}
}
return SCCs
}
