public static void dfsVisit(Vertex2 u) {
System.out.print(str[u.getIndex()] + "-->");
time++;
u.setD(time);
u.setColor("GRAY");
LinkedList<Vertex2> u_adj = adjacency_list[u.getIndex()];
for (Iterator iterator = u_adj.iterator(); iterator.hasNext(); ) {
Vertex2 v = (Vertex2) iterator.next();
if (v.getColor().equals("WHITE")) {
v.setPre(u.getIndex());
dfsVisit(v);
}
}
time++;
u.setF(time);
u.setColor("BLACK");
}
public static void main(String[] args) {
adjacency_list = new LinkedList[8];
vs = new Vertex2[8];
for (int i = 0; i < adjacency_list.length; i++) {
Vertex2 temp = new Vertex2(i);
temp.setColor("WHITE");
vs[i] = temp;
}
// 初始化邻接表
LinkedList<Vertex2> list0 = new LinkedList<Vertex2>();
list0.add(vs[1]);
list0.add(vs[4]);
adjacency_list[0] = list0;
LinkedList<Vertex2> list1 = new LinkedList<Vertex2>();
list1.add(vs[0]);
list1.add(vs[5]);
adjacency_list[1] = list1;
LinkedList<Vertex2> list2 = new LinkedList<Vertex2>();
list2.add(vs[3]);
list2.add(vs[5]);
list2.add(vs[6]);
adjacency_list[2] = list2;
LinkedList<Vertex2> list3 = new LinkedList<Vertex2>();
list3.add(vs[2]);
list3.add(vs[6]);
list3.add(vs[7]);
adjacency_list[3] = list3;
LinkedList<Vertex2> list4 = new LinkedList<Vertex2>();
list4.add(vs[0]);
adjacency_list[4] = list4;
LinkedList<Vertex2> list5 = new LinkedList<Vertex2>();
list5.add(vs[1]);
list5.add(vs[2]);
list5.add(vs[6]);
adjacency_list[5] = list5;
LinkedList<Vertex2> list6 = new LinkedList<Vertex2>();
list6.add(vs[2]);
list6.add(vs[3]);
list6.add(vs[5]);
list6.add(vs[7]);
adjacency_list[6] = list6;
LinkedList<Vertex2> list7 = new LinkedList<Vertex2>();
list7.add(vs[3]);
list7.add(vs[6]);
adjacency_list[7] = list7;
// DFS
System.out.println("DFS遍历序列");
for (int i = 0; i < vs.length; i++) {
Vertex2 u = vs[i];
if (u.getColor().equals("WHITE")) {
dfsVisit(u);
}
}
System.out.println();
System.out.println("拓扑排序序列");
// 拓扑序列即为深搜后按完成时间的倒序
Arrays.sort(vs);
for (int i = 0; i < vs.length; i++) {
System.out.print(str[vs[i].getIndex()] + " ");
}
System.out.println();
}
@Override
public int compareTo(Object obj) {
Vertex2 vertex2 = (Vertex2) obj;
return vertex2.getF() - this.f;
}